@article{GiesersKamannDreizleretal.2019, author = {Giesers, Benjamin David and Kamann, Sebastian and Dreizler, Stefan and Husser, Tim-Oliver and Askar, Abbas and G{\"o}ttgens, Fabian and Brinchmann, Jarle and Latour, Marilyn and Weilbacher, Peter Michael and Wendt, Martin and Roth, Martin M.}, title = {A stellar census in globular clusters with MUSE: Binaries in NGC 3201}, series = {Astronomy and astrophysics : an international weekly journal}, volume = {632}, journal = {Astronomy and astrophysics : an international weekly journal}, publisher = {EDP Sciences}, address = {Les Ulis}, issn = {0004-6361}, doi = {10.1051/0004-6361/201936203}, pages = {20}, year = {2019}, abstract = {We utilise multi-epoch MUSE spectroscopy to study binary stars in the core of the Galactic globular cluster NGC 3201. Our sample consists of 3553 stars with 54 883 spectra in total comprising 3200 main-sequence stars up to 4 magnitudes below the turn-off. Each star in our sample has between 3 and 63 (with a median of 14) reliable radial velocity measurements within five years of observations. We introduce a statistical method to determine the probability of a star showing radial velocity variations based on the whole inhomogeneous radial velocity sample. Using HST photometry and an advanced dynamical MOCCA simulation of this specific cluster we overcome observational biases that previous spectroscopic studies had to deal with. This allows us to infer a binary frequency in the MUSE field of view and enables us to deduce the underlying true binary frequency of (6.75 +/- 0.72)\% in NGC 3201. The comparison of the MUSE observations with the MOCCA simulation suggests a large portion of primordial binaries. We can also confirm a radial increase in the binary fraction towards the cluster centre due to mass segregation. We discovered that in the core of NGC 3201 at least (57.5 +/- 7.9)\% of blue straggler stars are in a binary system. For the first time in a study of globular clusters, we were able to fit Keplerian orbits to a significant sample of 95 binaries. We present the binary system properties of eleven blue straggler stars and the connection to SX Phoenicis-type stars. We show evidence that two blue straggler formation scenarios, the mass transfer in binary (or triple) star systems and the coalescence due to binary-binary interactions, are present in our data. We also describe the binary and spectroscopic properties of four sub-subgiant (or red straggler) stars. Furthermore, we discovered two new black hole candidates with minimum masses (M sin i) of (7.68 +/- 0.50)M-circle dot, (4.4 +/- 2.8)M-circle dot, and refine the minimum mass estimate on the already published black hole to (4.53 +/- 0.21)M-circle dot, These black holes are consistent with an extensive black hole subsystem hosted by NGC 3201.}, language = {en} } @article{GoettgensWeilbacherRothetal.2019, author = {G{\"o}ttgens, Fabian and Weilbacher, Peter Michael and Roth, Martin M. and Dreizler, Stefan and Giesers, Benjamin and Husser, Tim-Oliver and Kamann, Sebastian and Brinchmann, Jarle and Kollatschny, Wolfram and Monreal-Ibero, Ana and Schmidt, Kasper Borello and Wendt, Martin and Wisotzki, Lutz and Bacon, Roland}, title = {Discovery of an old nova remnant in the Galactic globular cluster M 22}, series = {Astronomy and astrophysics : an international weekly journal}, volume = {626}, journal = {Astronomy and astrophysics : an international weekly journal}, publisher = {EDP Sciences}, address = {Les Ulis}, issn = {1432-0746}, doi = {10.1051/0004-6361/201935221}, pages = {6}, year = {2019}, abstract = {A nova is a cataclysmic event on the surface of a white dwarf in a binary system that increases the overall brightness by several orders of magnitude. Although binary systems with a white dwarf are expected to be overabundant in globular clusters compared with in the Galaxy, only two novae from Galactic globular clusters have been observed. We present the discovery of an emission nebula in the Galactic globular cluster M 22 (NGC 6656) in observations made with the integral-field spectrograph MUSE. We extracted the spectrum of the nebula and used the radial velocity determined from the emission lines to confirm that the nebula is part of NGC 6656. Emission-line ratios were used to determine the electron temperature and density. It is estimated to have a mass of 1-17 x 10(-5) M-circle dot. This mass and the emission-line ratios indicate that the nebula is a nova remnant. Its position coincides with the reported location of a "guest star", an ancient Chinese term for transients, observed in May 48 BCE. With this discovery, this nova may be one of the oldest confirmed extra-solar events recorded in human history.}, language = {en} } @article{KamannHusserDreizleretal.2017, author = {Kamann, Sebastian and Husser, T. -O. and Dreizler, S. and Emsellem, E. and Weilbacher, Peter Michael and Martens, S. and Bacon, R. and den Brok, M. and Giesers, B. and Krajnovic, Davor and Roth, Martin M. and Wendt, Martin and Wisotzki, Lutz}, title = {A stellar census in globular clusters with MUSE}, series = {Monthly notices of the Royal Astronomical Society}, volume = {473}, journal = {Monthly notices of the Royal Astronomical Society}, number = {4}, publisher = {Oxford Univ. Press}, address = {Oxford}, issn = {0035-8711}, doi = {10.1093/mnras/stx2719}, pages = {5591 -- 5616}, year = {2017}, abstract = {This is the first of a series of papers presenting the results from our survey of 25 Galactic globular clusters with the MUSE integral-field spectrograph. In combination with our dedicated algorithm for source deblending, MUSE provides unique multiplex capabilities in crowded stellar fields and allows us to acquire samples of up to 20 000 stars within the half-light radius of each cluster. The present paper focuses on the analysis of the internal dynamics of 22 out of the 25 clusters, using about 500 000 spectra of 200 000 individual stars. Thanks to the large stellar samples per cluster, we are able to perform a detailed analysis of the central rotation and dispersion fields using both radial profiles and two-dimensional maps. The velocity dispersion profiles we derive show a good general agreement with existing radial velocity studies but typically reach closer to the cluster centres. By comparison with proper motion data, we derive or update the dynamical distance estimates to 14 clusters. Compared to previous dynamical distance estimates for 47 Tuc, our value is in much better agreement with other methods. We further find significant (>3 sigma) rotation in the majority (13/22) of our clusters. Our analysis seems to confirm earlier findings of a link between rotation and the ellipticities of globular clusters. In addition, we find a correlation between the strengths of internal rotation and the relaxation times of the clusters, suggesting that the central rotation fields are relics of the cluster formation that are gradually dissipated via two-body relaxation.}, language = {en} } @article{GoettgensHusserKamannetal.2019, author = {G{\"o}ttgens, Fabian and Husser, Tim-Oliver and Kamann, Sebastian and Dreizler, Stefan and Giesers, Benjamin and Kollatschny, Wolfram and Weilbacher, Peter Michael and Roth, Martin M. and Wendt, Martin}, title = {A stellar census in globular clusters with MUSE: A spectral catalogue of emission-line sources}, series = {Astronomy and astrophysics : an international weekly journal}, volume = {631}, journal = {Astronomy and astrophysics : an international weekly journal}, publisher = {EDP Sciences}, address = {Les Ulis}, issn = {0004-6361}, doi = {10.1051/0004-6361/201936485}, pages = {16}, year = {2019}, abstract = {Aims. Globular clusters produce many exotic stars due to a much higher frequency of dynamical interactions in their dense stellar environments. Some of these objects were observed together with several hundred thousand other stars in our MUSE survey of 26 Galactic globular clusters. Assuming that at least a few exotic stars have exotic spectra (i.e. spectra that contain emission lines), we can use this large spectroscopic data set of over a million stellar spectra as a blind survey to detect stellar exotica in globular clusters. Methods. To detect emission lines in each spectrum, we modelled the expected shape of an emission line as a Gaussian curve. This template was used for matched filtering on the di fferences between each observed 1D spectrum and its fitted spectral model. The spectra with the most significant detections of H alpha emission are checked visually and cross-matched with published catalogues. Results. We find 156 stars with H alpha emission, including several known cataclysmic variables (CV) and two new CVs, pulsating variable stars, eclipsing binary stars, the optical counterpart of a known black hole, several probable sub-subgiants and red stragglers, and 21 background emission-line galaxies. We find possible optical counterparts to 39 X-ray sources, as we detected H alpha emission in several spectra of stars that are close to known positions of Chandra X-ray sources. This spectral catalogue can be used to supplement existing or future X-ray or radio observations with spectra of potential optical counterparts to classify the sources.}, language = {en} } @article{WeilbacherMonrealIberoVerhammeetal.2018, author = {Weilbacher, Peter Michael and Monreal-Ibero, Ana and Verhamme, Anne and Sandin, Christer and Steinmetz, Matthias and Kollatschny, Wolfram and Krajnovic, Davor and Kamann, Sebastian and Roth, Martin M. and Erroz-Ferrer, Santiago and Marino, Raffaella Anna and Maseda, Michael V. and Wendt, Martin and Bacon, Roland and Dreizler, Stefan and Richard, Johan and Wisotzki, Lutz}, title = {Lyman-continuum leakage as dominant source of diffuse ionized gas in the Antennae galaxy}, series = {Astronomy and astrophysics : an international weekly journal}, volume = {611}, journal = {Astronomy and astrophysics : an international weekly journal}, publisher = {EDP Sciences}, address = {Les Ulis}, issn = {1432-0746}, doi = {10.1051/0004-6361/201731669}, pages = {17}, year = {2018}, abstract = {The Antennae galaxy (NGC 4038/39) is the closest major interacting galaxy system and is therefore often studied as a merger prototype. We present the first comprehensive integral field spectroscopic dataset of this system, observed with the MUSE instrument at the ESO VLT. We cover the two regions in this system which exhibit recent star formation: the central galaxy interaction and a region near the tip of the southern tidal tail. In these fields, we detect H II regions and diffuse ionized gas to unprecedented depth. About 15\% of the ionized gas was undetected by previous observing campaigns. This newly detected faint ionized gas is visible everywhere around the central merger, and shows filamentary structure. We estimate diffuse gas fractions of about 60\% in the central field and 10\% in the southern region. We are able to show that the southern region contains a significantly different population of H II regions, showing fainter luminosities. By comparing H II region luminosities with the HST catalog of young star clusters in the central field, we estimate that there is enough Lyman-continuum leakage in the merger to explain the amount of diffuse ionized gas that we detect. We compare the Lyman-continuum escape fraction of each H II region against emission line ratios that are sensitive to the ionization parameter. While we find no systematic trend between these properties, the most extreme line ratios seem to be strong indicators of density bounded ionization. Extrapolating the Lyman-continuum escape fractions to the southern region, we conclude that simply from the comparison of the young stellar populations to the ionized gas there is no need to invoke other ionization mechanisms than Lyman-continuum leaking H II regions for the diffuse ionized gas in the Antennae.}, language = {en} } @article{RahmaniWendtSrianandetal.2013, author = {Rahmani, H. and Wendt, Martin and Srianand, R. and Noterdaeme, P. and Petitjean, P. and Molaro, P. and Whitmore, J. B. and Murphy, M. T. and Centurion, Martin and Fathivavsari, H. and D'Odorico, S. and Evans, T. M. and Levshakov, S. A. and Lopez, S. and Martins, C. J. A. P. and Reimers, D. and Vladilo, G.}, title = {The UVES large program for testing fundamental physics - II. Constraints on a change in mu towards quasar HE 0027-1836}, series = {Monthly notices of the Royal Astronomical Society}, volume = {435}, journal = {Monthly notices of the Royal Astronomical Society}, number = {1}, publisher = {Oxford Univ. Press}, address = {Oxford}, issn = {0035-8711}, doi = {10.1093/mnras/stt1356}, pages = {861 -- 878}, year = {2013}, abstract = {We present an accurate analysis of the H-2 absorption lines from the z(abs) similar to 2.4018 damped Ly alpha system towards HE 0027-1836 observed with the Very Large Telescope Ultraviolet and Visual Echelle Spectrograph (VLT/UVES) as a part of the European Southern Observatory Large Programme 'The UVES large programme for testing fundamental physics' to constrain the variation of proton-to-electron mass ratio, mu m(p)/m(e). We perform cross-correlation analysis between 19 individual exposures taken over three years and the combined spectrum to check the wavelength calibration stability. We notice the presence of a possible wavelength-dependent velocity drift especially in the data taken in 2012. We use available asteroids spectra taken with UVES close to our observations to confirm and quantify this effect. We consider single-and two-component Voigt profiles to model the observed H-2 absorption profiles. We use both linear regression analysis and Voigt profile fitting where Delta mu/mu is explicitly considered as an additional fitting parameter. The two-component model is marginally favoured by the statistical indicators and we get Delta mu/mu = -2.5 +/- 8.1(stat) +/- 6.2(sys) ppm. When we apply the correction to the wavelength-dependent velocity drift, we find Delta mu/mu = -7.6 +/- 8.1(stat) +/- 6.3(sys) ppm. It will be important to check the extent to which the velocity drift we notice in this study is present in UVES data used for previous Delta mu/mu measurements.}, language = {en} } @article{MolaroCenturionWhitmoreetal.2013, author = {Molaro, P. and Centurion, Martin and Whitmore, J. B. and Evans, T. M. and Murphy, M. T. and Agafonova, I. I. and Bonifacio, P. and D'Odorico, S. and Levshakov, S. A. and Lopez, S. and Martins, C. J. A. P. and Petitjean, P. and Rahmani, H. and Reimers, D. and Srianand, R. and Vladilo, G. and Wendt, Martin}, title = {The UVES Large Program for testing fundamental physics I. Bounds on a change in alpha towards quasar HE 221-2818}, series = {Astronomy and astrophysics : an international weekly journal}, volume = {555}, journal = {Astronomy and astrophysics : an international weekly journal}, number = {4}, publisher = {EDP Sciences}, address = {Les Ulis}, issn = {0004-6361}, doi = {10.1051/0004-6361/201321351}, pages = {17}, year = {2013}, abstract = {Context. Absorption-line systems detected in quasar spectra can be used to compare the value of the fine-structure constant, alpha, measured today on Earth with its value in distant galaxies. In recent years, some evidence has emerged of small temporal and also spatial variations in alpha on cosmological scales. These variations may reach a fractional level of approximate to 10 ppm (parts per million). Aims. To test these claims we are conducting a Large Program of observations with the Very Large Telescope's Ultraviolet and Visual Echelle Spectrograph (UVES), and are obtaining high-resolution (R approximate to 60 000) and high signal-to-noise ratio (S/N approximate to 100) UVES spectra calibrated specifically for this purpose. Here we analyse the first complete quasar spectrum from this programme, that of HE 2217-2818. Methods. We applied the many multiplet method to measure alpha in five absorption systems towards this quasar: z(abs) = 0.7866, 0.9424, 1.5558, 1.6279, and 1.6919. Results. The most precise result is obtained for the absorber at z(abs) = 1.6919 where 3 Fe II transitions and Al II lambda 1670 have high S/N and provide a wide range of sensitivities to alpha. The absorption profile is complex with several very narrow features, and it requires 32 velocity components to be fitted to the data. We also conducted a range of tests to estimate the systematic error budget. Our final result for the relative variation in alpha in this system is Delta alpha/alpha = +1.3 +/- 2.4(stat) +/- 1.0(sys) ppm. This is one of the tightest current bounds on alpha-variation from an individual absorber. A second, separate approach to the data reduction, calibration, and analysis of this system yielded a slightly different result of -3.8 +/- 2.1(stat) ppm, possibly suggesting a larger systematic error component than our tests indicated. This approach used an additional 3 Fe II transitions, parts of which were masked due to contamination by telluric features. Restricting this analysis to the Fe II transitions alone and using a modified absorption profile model gave a result that is consistent with the first approach, Delta alpha/alpha = +1.1 +/- 2.6(stat) ppm. The four other absorbers have simpler absorption profiles, with fewer and broader features, and offer transitions with a narrower range of sensitivities to alpha. They therefore provide looser bounds on Delta alpha/alpha at the greater than or similar to 10 ppm precision level. Conclusions. The absorbers towards quasar HE 2217-2818 reveal no evidence of any variation in alpha at the 3-ppm precision level (1 sigma confidence). If the recently reported 10-ppm dipolar variation in alpha across the sky is correct, the expectation at this sky position is (3.2-5.4) +/- 1.7 ppm depending on dipole model used. Our constraint of Delta alpha/alpha = +1.3 +/- 2.4(stat) +/- 1.0(sys) ppm is not inconsistent with this expectation.}, language = {en} } @article{EvansMurphyWhitmoreetal.2014, author = {Evans, T. M. and Murphy, M. T. and Whitmore, J. B. and Misawa, T. and Centurion, Martin and Lopez, S. and Martins, C. J. A. P. and Molaro, P. and Petitjean, P. and Rahmani, H. and Srianand, R. and Wendt, Martin}, title = {The UVES Large Program for testing fundamental physics - III. Constraints on the fine-structure constant from three telescopes}, series = {Monthly notices of the Royal Astronomical Society}, volume = {445}, journal = {Monthly notices of the Royal Astronomical Society}, number = {1}, publisher = {Oxford Univ. Press}, address = {Oxford}, issn = {0035-8711}, doi = {10.1093/mnras/stu1754}, pages = {128 -- 150}, year = {2014}, language = {en} } @article{BonifacioRahmaniWhitmoreetal.2014, author = {Bonifacio, P. and Rahmani, H. and Whitmore, J. B. and Wendt, Martin and Centurion, Martin and Molaro, P. and Srianand, R. and Murphy, M. T. and Petitjean, P. and Agafonova, I. I. and Evans, T. M. and Levshakov, S. A. and Lopez, S. and Martins, C. J. A. P. and Reimers, D. and Vladilo, G.}, title = {Fundamental constants and high-resolution spectroscopy}, series = {Astronomische Nachrichten = Astronomical notes}, volume = {335}, journal = {Astronomische Nachrichten = Astronomical notes}, number = {1}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0004-6337}, doi = {10.1002/asna.201312005}, pages = {83 -- 91}, year = {2014}, language = {en} } @article{BoucheFinleySchroetteretal.2016, author = {Bouche, Nicolas and Finley, H. and Schroetter, I. and Murphy, M. T. and Richter, Philipp and Bacon, Roland and Contini, Thierry and Richard, J. and Wendt, Martin and Kamann, S. and Epinat, Benoit and Cantalupo, Sebastiano and Straka, Lorrie A. and Schaye, Joop and Martin, C. L. and Peroux, C. and Wisotzki, Lutz and Soto, K. and Lilly, S. and Carollo, C. M. and Brinchmann, Jarle and Kollatschny, W.}, title = {POSSIBLE SIGNATURES OF A COLD-FLOW DISK FROM MUSE USING A z similar to 1 GALAXY-QUASAR PAIR TOWARD SDSS J1422-0001}, series = {The astrophysical journal : an international review of spectroscopy and astronomical physics}, volume = {820}, journal = {The astrophysical journal : an international review of spectroscopy and astronomical physics}, publisher = {IOP Publ. Ltd.}, address = {Bristol}, issn = {0004-637X}, doi = {10.3847/0004-637X/820/2/121}, pages = {1872 -- 1882}, year = {2016}, abstract = {We use a background quasar to detect the presence of circumgalactic gas around a z = 0.91 low-mass star-forming galaxy. Data from the new Multi Unit Spectroscopic Explorer (MUSE) on the Very Large Telescope show that the galaxy has a dust-corrected star formation rate (SFR) of 4.7 +/- 2.0. M-circle dot yr(-1), with no companion down to 0.22 M-circle dot yr(-1) (5 sigma) within 240 h(-1) kpc ("30"). Using a high-resolution spectrum of the background quasar, which is fortuitously aligned with the galaxy major axis (with an azimuth angle alpha of only 15 degrees), we find, in the gas kinematics traced by low-ionization lines, distinct signatures consistent with those expected for a "cold-flow disk" extending at least 12 kpc (3 x R-1/2). We estimate the mass accretion rate M-in to be at least two to three times larger than the SFR, using the geometric constraints from the IFU data and the H (I) column density of log N-H (I)/cm(-2) similar or equal to 20.4 obtained from a Hubble Space Telescope/COS near-UV spectrum. From a detailed analysis of the low-ionization lines (e.g., Zn II, Cr II, Ti II, MnII, Si II), the accreting material appears to be enriched to about 0.4 Z(circle dot) (albeit with large uncertainties: log Z/Z(circle dot) = -0.4 +/- 0.4), which is comparable to the galaxy metallicity (12 + log O/H = 8.7 +/- 0.2), implying a large recycling fraction from past outflows. Blueshifted Mg II and Fe II absorptions in the galaxy spectrum from the MUSE data reveal the presence of an outflow. The Mg II and Fe II absorption line ratios indicate emission infilling due to scattering processes, but the MUSE data do not show any signs of fluorescent Fe II* emission.}, language = {en} } @article{HusserKamannDreizleretal.2016, author = {Husser, Tim-Oliver and Kamann, Sebastian and Dreizler, Stefan and Wendt, Martin and Wulff, Nina and Bacon, Roland and Wisotzki, Lutz and Brinchmann, Jarle and Weilbacher, Peter Michael and Roth, Martin M. and Monreal-Ibero, Ana}, title = {MUSE crowded field 3D spectroscopy of over 12 000 stars in the globular cluster NGC 6397 I. The first comprehensive HRD of a globular cluster}, series = {Nucleic acids research}, volume = {588}, journal = {Nucleic acids research}, publisher = {EDP Sciences}, address = {Les Ulis}, issn = {1432-0746}, doi = {10.1051/0004-6361/201526949}, pages = {14}, year = {2016}, abstract = {Aims. We demonstrate the high multiplex advantage of crowded field 3D spectroscopy with the new integral field spectrograph MUSE by means of a spectroscopic analysis of more than 12 000 individual stars in the globular cluster NGC 6397. Methods. The stars are deblended with a point spread function fitting technique, using a photometric reference catalogue from HST as prior, including relative positions and brightnesses. This catalogue is also used for a first analysis of the extracted spectra, followed by an automatic in-depth analysis via a full-spectrum fitting method based on a large grid of PHOENIX spectra. Results. We analysed the largest sample so far available for a single globular cluster of 18 932 spectra from 12 307 stars in NGC 6397. We derived a mean radial velocity of v(rad) = 17.84 +/- 0.07 km s(-1) and a mean metallicity of [Fe/H] = -2.120 +/- 0.002, with the latter seemingly varying with temperature for stars on the red giant branch (RGB). We determine Teff and [Fe/H] from the spectra, and log g from HST photometry. This is the first very comprehensive Hertzsprung-Russell diagram (HRD) for a globular cluster based on the analysis of several thousands of stellar spectra, ranging from the main sequence to the tip of the RGB. Furthermore, two interesting objects were identified; one is a post-AGB star and the other is a possible millisecond-pulsar companion.}, language = {en} } @article{UlmannWendtKloeckl2020, author = {Ulmann, Bernd and Wendt, Martin and Kl{\"o}ckl, Ingo}, title = {Medientechnisches Wissen}, series = {Band 3: Mathematik, Physik, Chemie}, journal = {Band 3: Mathematik, Physik, Chemie}, editor = {H{\"o}ltgen, Stefan}, publisher = {de Gruyter}, address = {Berlin}, isbn = {978-3-11-049626-0}, doi = {10.1515/9783110496277}, pages = {XVI, 442}, year = {2020}, abstract = {Das mehrb{\"a}ndige Lehrbuch vermittelt Studierenden und Medienwissenschaftlern eine Einf{\"u}hrung aus den Naturwissenschaften, Ingenieurwissenschaften und Technik-Disziplinen. Dabei steht im Zentrum, die Lesekompetenz f{\"u}r die jeweilige Disziplin zu etablieren und zu verbessern, damit innerhalb medien- und kulturwissenschaftlicher Studienprogramme Fachtexte der einzelnen Disziplinen diskutiert werden k{\"o}nnen}, language = {de} } @article{SchroetterBoucheZabletal.2019, author = {Schroetter, Ilane and Bouche, Nicolas F. and Zabl, Johannes and Contini, Thierry and Wendt, Martin and Schaye, Joop and Mitchell, Peter and Muzahid, Sowgat and Marino, Raffaella Anna and Bacon, Roland and Lilly, Simon J. and Richard, Johan and Wisotzki, Lutz}, title = {MusE GAs FLOw andWind (MEGAFLOW)}, series = {Monthly notices of the Royal Astronomical Society}, volume = {490}, journal = {Monthly notices of the Royal Astronomical Society}, number = {3}, publisher = {Oxford Univ. Press}, address = {Oxford}, issn = {0035-8711}, doi = {10.1093/mnras/stz2822}, pages = {4368 -- 4381}, year = {2019}, abstract = {We present results from our on-going MusE GAs FLOw and Wind (MEGAFLOW) survey, which consists of 22 quasar lines of sight, each observed with the integral field unit MUSE and the UVES spectrograph at the ESO Very Large Telescopes (VLT). The goals of this survey are to study the properties of the circumgalactic medium around z similar to 1 star-forming galaxies. The absorption-line selected survey consists of 79 strong MgII absorbers (with rest-frame equivalent width greater than or similar to 0.3 angstrom) and, currently, 86 associated galaxies within 100 projected kpc of the quasar with stellar masses (M-star) from 109 to 1011 M-circle dot. We find that the cool halo gas traced by MgII is not isotropically distributed around these galaxies from the strong bi-modal distribution in the azimuthal angle of the apparent location of the quasar with respect to the galaxy major axis. This supports a scenario in which outflows are bi-conical in nature and co-exist with a co-planar gaseous structure extending at least up to 60-80 kpc. Assuming that absorbers near the minor axis probe outflows, the current MEGAFLOW sample allowed us to select 26 galaxy-quasar pairs suitable for studying winds. From this sample, using a simple geometrical model, we find that the outflow velocity only exceeds the escape velocity when M-star less than or similar to 4 x 10(9) M-circle dot, implying the cool material is likely to fall back except in the smallest haloes. Finally, we find that the mass loading factor., the ratio between the ejected mass rate and the star formation rate, appears to be roughly constant with respect to the galaxy mass.}, language = {en} } @article{LatourHusserGiesersetal.2019, author = {Latour, Marlyn and Husser, Tim Oliver and Giesers, Benjamin David and Kamann, S. and G{\"o}ttgens, Fabian and Dreizler, Stefan and Brinchmann, Jan and Bastian, Nate and Wendt, Martin and Weilbacher, Peter Michael and Molinski, N. S.}, title = {A stellar census in globular clusters with MUSE: multiple populations chemistry in NGC 2808 star star star}, series = {Astronomy and astrophysics : an international weekly journal}, volume = {631}, journal = {Astronomy and astrophysics : an international weekly journal}, publisher = {EDP Sciences}, address = {Les Ulis}, issn = {1432-0746}, doi = {10.1051/0004-6361/201936242}, pages = {14}, year = {2019}, abstract = {Context. Galactic globular clusters (GCs) are now known to host multiple populations displaying particular abundance variations. The different populations within a GC can be well distinguished following their position in the pseudo two-colors diagrams, also referred to as "chromosome maps". These maps are constructed using optical and near-UV photometry available from the Hubble Space Telescope (HST) UV survey of GCs. However, the chemical tagging of the various populations in the chromosome maps is hampered by the fact that HST photometry and elemental abundances are both only available for a limited number of stars. Aims. The spectra collected as part of the MUSE survey of globular clusters provide a spectroscopic counterpart to the HST photometric catalogs covering the central regions of GCs. In this paper, we use the MUSE spectra of 1115 red giant branch (RGB) stars in NGC 2808 to characterize the abundance variations seen in the multiple populations of this cluster. Methods. We used the chromosome map of NGC 2808 to divide the RGB stars into their respective populations. We then combined the spectra of all stars belonging to a given population, resulting in one high signal-to-noise ratio spectrum representative of each population. Results. Variations in the spectral lines of O, Na, Mg, and Al are clearly detected among four of the populations. In order to quantify these variations, we measured equivalent width differences and created synthetic populations spectra that were used to determine abundance variations with respect to the primordial population of the cluster. Our results are in good agreement with the values expected from previous studies based on high-resolution spectroscopy. We do not see any significant variations in the spectral lines of Ca, K, and Ba. We also do not detect abundance variations among the stars belonging to the primordial population of NGC 2808. Conclusions. We demonstrate that in spite of their low resolution, the MUSE spectra can be used to investigate abundance variations in the context of multiple populations.}, language = {en} } @article{MonrealIberoWeilbacherWendt2018, author = {Monreal-Ibero, Ana and Weilbacher, Peter Michael and Wendt, Martin}, title = {Diffuse interstellar bands lambda 5780 and lambda 5797 in the Antennae Galaxy as seen by MUSE}, series = {Astronomy and astrophysics : an international weekly journal}, volume = {615}, journal = {Astronomy and astrophysics : an international weekly journal}, publisher = {EDP Sciences}, address = {Les Ulis}, issn = {1432-0746}, doi = {10.1051/0004-6361/201732178}, pages = {12}, year = {2018}, abstract = {Context. Diffuse interstellar bands (DIBs) are faint spectral absorption features of unknown origin. Research on DIBs beyond the Local Group is very limited and will surely blossom in the era of the Extremely Large Telescopes. However, we can already start paving the way. One possibility that needs to be explored is the use of high-sensitivity integral field spectrographs. Aims. Our goals are twofold. First, we aim to derive reliable mapping of at least one DIB in a galaxy outside the Local Group. Second, we want to explore the relation between DIBs and other properties of the interstellar medium (ISM) in the galaxy. Methods. We use Multi Unit Spectroscopic Explorer (MUSE) data for the Antennae Galaxy, the closest major galaxy merger. High signal-to-noise spectra were created by co-adding the signal of many spatial elements with the Voronoi binning technique. The emission of the underlying stellar population was modelled and substracted with the STARLIGHT spectral synthesis code. Flux and equivalent width of the features of interest were measured by means of fitting to Gaussian functions. Conclusions. The results illustrate the enormous potential of integral field spectrographs for extragalactic DIB research.}, language = {en} } @article{GuberRichterWendt2018, author = {Guber, Christoph Rudolf and Richter, Philipp and Wendt, Martin}, title = {Multiple origins for the DLA at zabs = 0.313 toward PKS 1127-145 indicated by a complex dust depletion pattern of Ca, Ti, and Mn}, series = {Astronomy and astrophysics : an international weekly journal}, volume = {609}, journal = {Astronomy and astrophysics : an international weekly journal}, publisher = {EDP Sciences}, address = {Les Ulis}, issn = {1432-0746}, doi = {10.1051/0004-6361/201730984}, pages = {9}, year = {2018}, abstract = {Aims: We aim to investigate the dust depletion properties of optically thick gas in and around galaxies and its origin we study in detail the dust depletion patterns of Ti, Mn, and Ca in the multi-component damped Lyman alpha (DLA) absorber at z(abs) = 0.313 toward the quasar PKS 1127-145. Methods: We performed a detailed spectral analysis of the absorption profiles of Ca II, Mn II, TIII, and Na I associated with the DLA toward PKS 1127-145, based on optical high-resolution data obtained with the UVES instrument at the Very Large Telescope. We obtained column densities and Doppler-parameters for the ions listed above and determine their gas-phase abundances, from which we conclude on their dust depletion properties. We compared the Ca and Ti depletion properties of this DLA with that of other DLAs. Results: One of the six analyzed absorption components (component 3) shows a striking underabundance of Ti and Mn in the gas-phase, indicating the effect of dust depletion for these elements and a locally enhanced dust-to-gas ratio. In this DLA and in other similar absorbers, the Mn II abundance follows that of Ti II very closely, implying that both ions are equally sensitive to the dust depletion effects. Conclusions: Our analysis indicates that the DLA toward PKS 1127 145 has multiple origins. With its narrow line width and its strong dust depletion, component 3 points toward the presence of a neutral gas disk from a faint LSB galaxy in front of PKS 1127 145, while the other, more diffuse and dust-poor, absorption components possibly are related to tidal gas features from the interaction between the various, optically confirmed galaxy-group members. In general, the Mn/Ca II ratio in sub-DLAs and DLAs possibly serves as an important indicator to discriminate between dust-rich and dust-poor in neutral gas in and around galaxies.}, language = {en} } @article{BoumaRichterWendt2021, author = {Bouma, Sietske Jeltje Deirdre and Richter, Philipp and Wendt, Martin}, title = {The relation between Ly alpha absorbers and local galaxy filaments}, series = {Astronomy and astrophysics : an international weekly journal}, volume = {647}, journal = {Astronomy and astrophysics : an international weekly journal}, publisher = {EDP Sciences}, address = {Les Ulis}, issn = {0004-6361}, doi = {10.1051/0004-6361/202039786}, pages = {16}, year = {2021}, abstract = {Context. The intergalactic medium (IGM) is believed to contain the majority of baryons in the universe and to trace the same dark matter structure as galaxies, forming filaments and sheets. Ly alpha absorbers, which sample the neutral component of the IGM, have been extensively studied at low and high redshift, but the exact relation between Ly alpha absorption, galaxies, and the large-scale structure is observationally not well constrained.Aims. In this study, we aim at characterising the relation between Ly alpha absorbers and nearby over-dense cosmological structures (galaxy filaments) at recession velocities Delta v <= 6700 km s(-1) by using archival observational data from various instruments.Methods. We analyse 587 intervening Ly alpha absorbers in the spectra of 302 extragalactic background sources obtained with the Cosmic Origins Spectrograph (COS) installed on the Hubble Space Telescope (HST). We combine the absorption line information with galaxy data of five local galaxy filaments from the V8k catalogue.Results. Along the 91 sightlines that pass close to a filament, we identify 215 (227) Ly alpha absorption systems (components). Among these, 74 Ly alpha systems are aligned in position and velocity with the galaxy filaments, indicating that these absorbers and the galaxies trace the same large-scale structure. The filament-aligned Ly alpha absorbers have a similar to 90\% higher rate of incidence (d?/dz=189 for log N(HI) >= 13.2) and a slightly shallower column density distribution function slope (-beta=-1.47) relative to the general Ly alpha population at z=0, reflecting the filaments' matter over-density. The strongest Ly alpha absorbers are preferentially found near galaxies or close to the axis of a filament, although there is substantial scatter in this relation. Our sample of absorbers clusters more strongly around filament axes than a randomly distributed sample would do (as confirmed by a Kolmogorov-Smirnov test), but the clustering signal is less pronounced than for the galaxies in the filaments.}, language = {en} } @article{MarinoCantalupoLillyetal.2018, author = {Marino, Raffaella Anna and Cantalupo, Sebastiano and Lilly, Simon J. and Gallego, Sofia G. and Straka, Lorrie A. and Borisova, Elena and Pezzulli, Gabriele and Bacon, Roland and Brinchmann, Jarle and Carollo, C. Marcella and Caruana, Joseph and Conseil, Simon and Contini, Thierry and Diener, Catrina and Finley, Hayley and Inami, Hanae and Leclercq, Floriane and Muzahid, Sowgat and Richard, Johan and Schaye, Joop and Wendt, Martin and Wisotzki, Lutz}, title = {Dark Galaxy Candidates at Redshift similar to 3.5 Detected with MUSE}, series = {The astrophysical journal : an international review of spectroscopy and astronomical physics}, volume = {859}, journal = {The astrophysical journal : an international review of spectroscopy and astronomical physics}, number = {1}, publisher = {IOP Publ. Ltd.}, address = {Bristol}, issn = {0004-637X}, doi = {10.3847/1538-4357/aab6aa}, pages = {22}, year = {2018}, abstract = {Recent theoretical models suggest that the early phase of galaxy formation could involve an epoch when galaxies are gas rich but inefficient at forming stars: a "dark galaxy" phase. Here, we report the results of our Multi-Unit Spectroscopic Explorer (MUSE) survey for dark galaxies fluorescently illuminated by quasars at z > 3. Compared to previous studies which are based on deep narrowband (NB) imaging, our integral field survey provides a nearly uniform sensitivity coverage over a large volume in redshift space around the quasars as well as full spectral information at each location. Thanks to these unique features, we are able to build control samples at large redshift distances from the quasars using the same data taken under the same conditions. By comparing the rest-frame equivalent width (EW0) distributions of the Ly alpha sources detected in proximity to the quasars and in control samples, we detect a clear correlation between the locations of high-EW0 objects and the quasars. This correlation is not seen in other properties, such as Ly alpha luminosities or volume overdensities, suggesting the possible fluorescent nature of at least some of these objects. Among these, we find six sources without continuum counterparts and EW0 limits larger than 240 angstrom that are the best candidates for dark galaxies in our survey at z > 3.5. The volume densities and properties, including inferred gas masses and star formation efficiencies, of these dark galaxy candidates are similar to those of previously detected candidates at z approximate to 2.4 in NB surveys. Moreover, if the most distant of these are fluorescently illuminated by the quasar, our results also provide a lower limit of t - 60 Myr on the quasar lifetime.}, language = {en} } @article{PaalvastVerhammeStrakaetal.2018, author = {Paalvast, M. and Verhamme, A. and Straka, L. A. and Brinchmann, J. and Herenz, Edmund Christian and Carton, D. and Gunawardhana, M. L. P. and Boogaard, L. A. and Cantalupo, S. and Contini, T. and Epinat, Benoit and Inami, H. and Marino, R. A. and Maseda, M. V. and Michel-Dansac, L. and Muzahid, S. and Nanayakkara, T. and Pezzulli, Gabriele and Richard, J. and Schaye, Joop and Segers, M. C. and Urrutia, Tanya and Wendt, Martin and Wisotzki, Lutz}, title = {Properties and redshift evolution of star-forming galaxies with high [0 III]/[O II] ratios with MUSE at 0.28 < z < 0.85}, series = {Astronomy and astrophysics : an international weekly journal}, volume = {618}, journal = {Astronomy and astrophysics : an international weekly journal}, publisher = {EDP Sciences}, address = {Les Ulis}, issn = {0004-6361}, doi = {10.1051/0004-6361/201832866}, pages = {15}, year = {2018}, abstract = {We present a study of the [O III]/[O II] ratios of star-forming galaxies drawn from Multi-Unit Spectroscopic Explorer (MUSE) data spanning a redshift range 0.28 < z < 0.85. Recently discovered Lyman continuum (LyC) emitters have extremely high oxygen line ratios: [O III]lambda 5007/[O II]lambda lambda 3726, 3729 > 4. Here we aim to understand the properties and the occurrences of galaxies with such high line ratios. Combining data from several MUSE Guaranteed Time Observing (GTO) programmes, we select a population of star-forming galaxies with bright emission lines, from which we draw 406 galaxies for our analysis based on their position in the z-dependent star formation rate (SFR) stellar mass (M*) plane. Out of this sample 15 are identified as extreme oxygen emitters based on their [O III]/[O II] ratios (3.7\%) and 104 galaxies have [O III]/[O II] > 1 (26\%). Our analysis shows no significant correlation between M*, SFR, and the distance from the SFR M, relation with [O III]/[O II]. We find a decrease in the fraction of galaxies with [O III]/[O II] > 1 with increasing M*, however, this is most likely a result of the relationship between [O III]/[O II] and metallicity, rather than between [O III]/[O II] and M. We draw a comparison sample of local analogues with < z > 0.03 from the Sloan Digital Sky Survey, and find similar incidence rates for this sample. In order to investigate the evolution in the fraction of high [O III]/[O II] emitters with redshift, we bin the sample into three redshift subsamples of equal number, but find no evidence for a dependence on redshift. Furthermore, we compare the observed line ratios with those predicted by nebular models with no LyC escape and find that most of the extreme oxygen emitters can be reproduced by low metallicity models. The remaining galaxies are likely LyC emitter candidates.}, language = {en} } @article{JohnsonChenStrakaetal.2018, author = {Johnson, Sean D. and Chen, Hsiao-Wen and Straka, Lorrie and Schaye, Joop and Cantalupo, Sebastiano and Wendt, Martin and Muzahid, Sowgat and Bouch{\´e}, Nicolas and Herenz, Edmund Christian and Kollatschny, Wolfram and Mulchaey, John S. and Marino, Raffaella A. and Maseda, Michael and Wisotzki, Lutz}, title = {Galaxy and quasar fueling caught in the act from the intragroup to the interstellar medium}, series = {The astrophysical journal : Part 2, Letters}, volume = {869}, journal = {The astrophysical journal : Part 2, Letters}, number = {1}, publisher = {IOP Publishing Ltd. (Bristol)}, address = {Bristol}, issn = {2041-8205}, doi = {10.3847/2041-8213/aaf1cf}, pages = {7}, year = {2018}, abstract = {We report the discovery of six spatially extended (10-100 kpc) line-emitting nebulae in the z approximate to 0.57 galaxy group hosting PKS 0405-123, one of the most luminous quasars at z < 1. The discovery is enabled by the Multi Unit Spectroscopic Explorer and provides tantalizing evidence connecting large-scale gas streams with nuclear activity on scales of <10 proper kpc (pkpc). One of the nebulae exhibits a narrow, filamentary morphology extending over 50 pkpc toward the quasar with narrow internal velocity dispersion (50 km s(-1)) and is not associated with any detected galaxies, consistent with a cool intragroup medium filament. Two of the nebulae are 10 pkpc north and south of the quasar with tidal-arm-like morphologies. These two nebulae, along with a continuum-emitting arm extending 60 pkpc from the quasar, are signatures of interactions that are expected to redistribute angular momentum in the host interstellar medium (ISM) to facilitate star formation and quasar fueling in the nucleus. The three remaining nebulae are among the largest and most luminous [O III] emitting "blobs" known (1400-2400 pkpc(2)) and correspond both kinematically and morphologically to interacting galaxy pairs in the quasar host group, consistent with arising from stripped ISM rather than large-scale quasar outflows. The presence of these large- and small-scale nebulae in the vicinity of a luminous quasar bears significantly on the effect of large-scale environment on galaxy and black hole fueling, providing a natural explanation for the previously known correlation between quasar luminosity and cool circumgalactic medium.}, language = {en} } @article{ChenJohnsonStrakaetal.2019, author = {Chen, Hsiao-Wen and Johnson, Sean D. and Straka, Lorrie A. and Zahedy, Fakhri S. and Schaye, Joop and Muzahid, Sowgat and Bouche, Nicolas and Cantalupo, Sebastiano and Marino, Raffaella Anna and Wendt, Martin}, title = {Characterizing circumgalactic gas around massive ellipticals at z approximate to 0.4-III.}, series = {Monthly notices of the Royal Astronomical Society}, volume = {484}, journal = {Monthly notices of the Royal Astronomical Society}, number = {1}, publisher = {Oxford Univ. Press}, address = {Oxford}, issn = {0035-8711}, doi = {10.1093/mnras/sty3513}, pages = {431 -- 441}, year = {2019}, abstract = {This paper presents a study of the galactic environment of a chemically pristine (<0.6 per cent solar metallicity) Lyman Limit system (LLS) discovered along the sightline towards QSO SDSSJ 135726.27+043541.4 (Z(QSO) = 1.233) at projected distance d = 126 physical kpc (pkpc) from a luminous red galaxy (LRG) at z = 0.33. Combining deep Hubble Space Telescope images, MUSE integral field spectroscopic data, and wide-field redshift survey data has enabled an unprecedented, ultradeep view of the environment around this LRG-LLS pair. A total of 12 galaxies, including the LRG, are found at d less than or similar to 400 pkpc and line-of-sight velocity Delta v < 600 km S-1 of the LLS, with intrinsic luminosity ranging from 0.001 L-* to 2 L-* and a corresponding stellar mass range of M-star approximate to 10(7-11) M-circle dot. All 12 galaxies contribute to a total mass of M-star = 1.6 x 10(11) M-circle dot with approximate to 80 per cent contained in the LRG. The line-of-sight velocity dispersion of these galaxies is found to be sigma (group) = 230 km s(-1) with the centre of mass at d(group) = 118 pkpc and line-of-sight velocity offset of Delta v(group) = 181 km s(-1) from the LLS. Three of these are located at d less than or similar to 100 pkpc from the LLS, and they are all faint with intrinsic luminosity less than or similar to 0.02 L-* and gas-phase metallicity of approximate to 10 per cent solar in their interstellar medium. The disparity in the chemical enrichment level between the LLS and the group members suggests that the LLS originates in infalling intergalactic medium and that parts of the intergalactic gas near old and massive galaxies can still remain chemically pristine through the not too distant past.}, language = {en} } @article{ZablBoucheSchroetteretal.2019, author = {Zabl, Johannes and Bouche, Nicolas F. and Schroetter, Ilane and Wendt, Martin and Finley, Hayley and Schaye, Joop and Conseil, Simon and Contini, Thierry and Marino, Raffaella Anna and Mitchell, Peter and Muzahid, Sowgat and Pezzulli, Gabriele and Wisotzki, Lutz}, title = {MusE GAs FLOw and Wind (MEGAFLOW)}, series = {Monthly notices of the Royal Astronomical Society}, volume = {485}, journal = {Monthly notices of the Royal Astronomical Society}, number = {2}, publisher = {Oxford Univ. Press}, address = {Oxford}, issn = {0035-8711}, doi = {10.1093/mnras/stz392}, pages = {1961 -- 1980}, year = {2019}, abstract = {We use the MusE GAs FLOw and Wind (MEGAFLOW) survey to study the kinematics of extended disc-like structures of cold gas around z approximate to 1 star-forming galaxies. The combination of VLT/MUSE and VLT/UVES observations allows us to connect the kinematics of the gas measured through MgII quasar absorption spectroscopy to the kinematics and orientation of the associated galaxies constrained through integral field spectroscopy. Confirming previous results, we find that the galaxy-absorber pairs of the MEGAFLOW survey follow a strong bimodal distribution, consistent with a picture of MgII absorption being predominantly present in outflow cones and extended disc-like structures. This allows us to select a bona-fide sample of galaxy-absorber pairs probing these discs for impact paramometers of 10-70 kpc. We test the hypothesis that the disc-like gas is co-rotating with the galaxy discs, and find that for seven out of nine pairs the absorption velocity shares the sign of the disc velocity, disfavouring random orbits. We further show that the data are roughly consistent with inflow velocities and angular momenta predicted by simulations, and that the corresponding mass accretion rates are sufficient to balance the star formation rates.}, language = {en} } @article{WisotzkiBaconBlaizotetal.2016, author = {Wisotzki, Lutz and Bacon, Roland and Blaizot, J. and Brinchmann, Jarle and Herenz, Edmund Christian and Schaye, Joop and Bouche, Nicolas and Cantalupo, Sebastiano and Contini, Thierry and Carollo, C. M. and Caruana, Joseph and Courbot, J. -B. and Emsellem, E. and Kamann, S. and Kerutt, Josephine Victoria and Leclercq, F. and Lilly, S. J. and Patricio, V. and Sandin, C. and Steinmetz, Matthias and Straka, Lorrie A. and Urrutia, Tanya and Verhamme, A. and Weilbacher, Peter Michael and Wendt, Martin}, title = {Extended Lyman alpha haloes around individual high-redshift galaxies revealed by MUSE}, series = {Science}, volume = {587}, journal = {Science}, publisher = {EDP Sciences}, address = {Les Ulis}, issn = {1432-0746}, doi = {10.1051/0004-6361/201527384}, pages = {27}, year = {2016}, abstract = {We report the detection of extended Ly alpha emission around individual star-forming galaxies at redshifts z = 3-6 in an ultradeep exposure of the Hubble Deep Field South obtained with MUSE on the ESO-VLT. The data reach a limiting surface brightness (1 sigma) of similar to 1 x 10(-19) erg s(-1) cm(-2) arcsec(-2) in azimuthally averaged radial profiles, an order of magnitude improvement over previous narrowband imaging. Our sample consists of 26 spectroscopically confirmed Ly alpha-emitting, but mostly continuum-faint (m(AB) greater than or similar to 27) galaxies. In most objects the Ly alpha emission is considerably more extended than the UV continuum light. While five of the faintest galaxies in the sample show no significantly detected Ly alpha haloes, the derived upper limits suggest that this is due to insufficient S/N. Ly alpha haloes therefore appear to be ubiquitous even for low-mass (similar to 10(8)-10(9) M-circle dot) star-forming galaxies at z > 3. We decompose the Ly alpha emission of each object into a compact component tracing the UV continuum and an extended halo component, and infer sizes and luminosities of the haloes. The extended Ly alpha emission approximately follows an exponential surface brightness distribution with a scale length of a few kpc. While these haloes are thus quite modest in terms of their absolute sizes, they are larger by a factor of 5-15 than the corresponding rest-frame UV continuum sources as seen by HST. They are also much more extended, by a factor similar to 5, than Ly alpha haloes around low-redshift star-forming galaxies. Between similar to 40\% and greater than or similar to 90\% of the observed Ly alpha flux comes from the extended halo component, with no obvious correlation of this fraction with either the absolute or the relative size of the Ly alpha halo. Our observations provide direct insights into the spatial distribution of at least partly neutral gas residing in the circumgalactic medium of low to intermediate mass galaxies at z > 3.}, language = {en} } @article{WendtWeymarJungeetal.2018, author = {Wendt, Julia and Weymar, Mathias and Junge, Martin and Hamm, Alfons O. and Lischke, Alexander}, title = {Heartfelt memories}, series = {Emotion : a new journal from the American Psychological Association}, volume = {19}, journal = {Emotion : a new journal from the American Psychological Association}, number = {1}, publisher = {American Psychological Association}, address = {Washington}, issn = {1528-3542}, doi = {10.1037/emo0000396}, pages = {178 -- 182}, year = {2018}, abstract = {During social interactions, we rapidly judge others' trustworthiness on basis of their facial characteristics. Face-based trustworthiness judgments may not only affect our current but also our future interactions because we seem to be more inclined to remember untrustworthy than trustworthy faces. Memory formation of salient stimuli like untrustworthy faces may be modulated by the interplay between the autonomic and central nervous system, which can be indexed by changes in vagally mediated heart rate variability (HRV). To test this assumption, we investigated whether differences in HRV would be associated with differences in memory formation of untrustworthy faces in a sample of healthy participants (n = 34, all female). Untrustworthy faces were remembered more accurately than trustworthy faces, albeit only by participants with high and not low HRV. Across participants, increased memory accuracy for untrustworthy faces was associated with increased HRV. We discuss these findings in the context of neurobiological theories regarding the interplay between the autonomic and central nervous system during the regulation of autonomic, emotional and cognitive processes. (PsycInfo Database Record}, language = {en} } @article{WendtLoewWeymaretal.2017, author = {Wendt, Julia and Loew, Andreas and Weymar, Mathias and Lotze, Martin and Hamm, Alfons O.}, title = {Active avoidance and attentive freezing in the face of approaching threat}, series = {NeuroImage : a journal of brain function}, volume = {158}, journal = {NeuroImage : a journal of brain function}, publisher = {Elsevier}, address = {San Diego}, issn = {1053-8119}, doi = {10.1016/j.neuroimage.2017.06.054}, pages = {196 -- 204}, year = {2017}, abstract = {Defensive behaviors in animals and humans vary dynamically with increasing proximity of a threat and depending upon the behavioral repertoire at hand. The current study investigated physiological and behavioral adjustments and associated brain activation when participants were exposed to dynamically approaching threat that was either inevitable or could be avoided by motor action. When the approaching threat was inevitable, attentive freezing was observed as indicated by fear bradycardia, startle potentiation, and a dynamic increase in activation of the anterior insula and the periaqueductal grey. In preparation for active avoidance a switch in defensive behavior was observed characterized by startle inhibition and heart rate acceleration along with potentiated activation of the amygdala and the periaqueductal grey. Importantly, the modulation of defensive behavior according to threat imminence and the behavioral option at hand was associated with activity changes in the ventromedial prefrontal cortex. These findings improve our understanding of brain mechanisms guiding human behavior during approaching threat depending on available resources.}, language = {en} } @article{PahnkeMauMoellerJungeetal.2019, author = {Pahnke, Rike and Mau-M{\"o}ller, Anett and Junge, Martin and Wendt, Julia and Weymar, Mathias and Hamm, Alfons O. and Lischke, Alexander}, title = {Oral Contraceptives Impair Complex Emotion Recognition in Healthy Women}, series = {Frontiers in neuroscience}, volume = {12}, journal = {Frontiers in neuroscience}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1662-453X}, doi = {10.3389/fnins.2018.01041}, pages = {9}, year = {2019}, abstract = {Despite the widespread use of oral contraceptives (OCs), remarkably little is known about the effects of OCs on emotion, cognition, and behavior. However, coincidental findings suggest that OCs impair the ability to recognize others' emotional expressions, which may have serious consequences in interpersonal contexts. To further investigate the effects of OCs on emotion recognition, we tested whether women who were using OCs (n = 42) would be less accurate in the recognition of complex emotional expressions than women who were not using OCs (n = 53). In addition, we explored whether these differences in emotion recognition would depend on women's menstrual cycle phase. We found that women with OC use were indeed less accurate in the recognition of complex expressions than women without OC use, in particular during the processing of expressions that were difficult to recognize. These differences in emotion recognition did not depend on women's menstrual cycle phase. Our findings, thus, suggest that OCs impair women's emotion recognition, which should be taken into account when informing women about the side-effects of OC use.}, language = {en} } @article{KoenigAblerAgartzetal.2020, author = {Koenig, Julian and Abler, Birgit and Agartz, Ingrid and akerstedt, Torbjorn and Andreassen, Ole A. and Anthony, Mia and Baer, Karl-Juergen and Bertsch, Katja and Brown, Rebecca C. and Brunner, Romuald and Carnevali, Luca and Critchley, Hugo D. and Cullen, Kathryn R. and de Geus, Eco J. C. and de la Cruz, Feliberto and Dziobek, Isabel and Ferger, Marc D. and Fischer, Hakan and Flor, Herta and Gaebler, Michael and Gianaros, Peter J. and Giummarra, Melita J. and Greening, Steven G. and Guendelman, Simon and Heathers, James A. J. and Herpertz, Sabine C. and Hu, Mandy X. and Jentschke, Sebastian and Kaess, Michael and Kaufmann, Tobias and Klimes-Dougan, Bonnie and Koelsch, Stefan and Krauch, Marlene and Kumral, Deniz and Lamers, Femke and Lee, Tae-Ho and Lekander, Mats and Lin, Feng and Lotze, Martin and Makovac, Elena and Mancini, Matteo and Mancke, Falk and Mansson, Kristoffer N. T. and Manuck, Stephen B. and Mather, Mara and Meeten, Frances and Min, Jungwon and Mueller, Bryon and Muench, Vera and Nees, Frauke and Nga, Lin and Nilsonne, Gustav and Ordonez Acuna, Daniela and Osnes, Berge and Ottaviani, Cristina and Penninx, Brenda W. J. H. and Ponzio, Allison and Poudel, Govinda R. and Reinelt, Janis and Ren, Ping and Sakaki, Michiko and Schumann, Andy and Sorensen, Lin and Specht, Karsten and Straub, Joana and Tamm, Sandra and Thai, Michelle and Thayer, Julian F. and Ubani, Benjamin and van Der Mee, Denise J. and van Velzen, Laura S. and Ventura-Bort, Carlos and Villringer, Arno and Watson, David R. and Wei, Luqing and Wendt, Julia and Schreiner, Melinda Westlund and Westlye, Lars T. and Weymar, Mathias and Winkelmann, Tobias and Wu, Guo-Rong and Yoo, Hyun Joo and Quintana, Daniel S.}, title = {Cortical thickness and resting-state cardiac function across the lifespan}, series = {Psychophysiology : journal of the Society for Psychophysiological Research}, volume = {58}, journal = {Psychophysiology : journal of the Society for Psychophysiological Research}, number = {7}, publisher = {Wiley}, address = {Hoboken}, issn = {0048-5772}, doi = {10.1111/psyp.13688}, pages = {16}, year = {2020}, abstract = {Understanding the association between autonomic nervous system [ANS] function and brain morphology across the lifespan provides important insights into neurovisceral mechanisms underlying health and disease. Resting-state ANS activity, indexed by measures of heart rate [HR] and its variability [HRV] has been associated with brain morphology, particularly cortical thickness [CT]. While findings have been mixed regarding the anatomical distribution and direction of the associations, these inconsistencies may be due to sex and age differences in HR/HRV and CT. Previous studies have been limited by small sample sizes, which impede the assessment of sex differences and aging effects on the association between ANS function and CT. To overcome these limitations, 20 groups worldwide contributed data collected under similar protocols of CT assessment and HR/HRV recording to be pooled in a mega-analysis (N = 1,218 (50.5\% female), mean age 36.7 years (range: 12-87)). Findings suggest a decline in HRV as well as CT with increasing age. CT, particularly in the orbitofrontal cortex, explained additional variance in HRV, beyond the effects of aging. This pattern of results may suggest that the decline in HRV with increasing age is related to a decline in orbitofrontal CT. These effects were independent of sex and specific to HRV; with no significant association between CT and HR. Greater CT across the adult lifespan may be vital for the maintenance of healthy cardiac regulation via the ANS-or greater cardiac vagal activity as indirectly reflected in HRV may slow brain atrophy. Findings reveal an important association between CT and cardiac parasympathetic activity with implications for healthy aging and longevity that should be studied further in longitudinal research.}, language = {en} } @article{MonrealIberoWeilbacherWendtetal.2015, author = {Monreal-Ibero, Ana and Weilbacher, Peter Michael and Wendt, Martin and Selman, Fernando and Lallement, Rosine and Brinchmann, Jarle and Kamann, Sebastian and Sandin, Christer}, title = {Towards DIB mapping in galaxies beyond 100 Mpc A radial profile of the lambda 5780.5 diffuse interstellar band in AM1353-272 B}, series = {Astronomy and astrophysics : an international weekly journal}, volume = {576}, journal = {Astronomy and astrophysics : an international weekly journal}, publisher = {EDP Sciences}, address = {Les Ulis}, issn = {0004-6361}, doi = {10.1051/0004-6361/201525854}, pages = {4}, year = {2015}, abstract = {Context. Diffuse interstellar bands (DIBs) are non-stellar weak absorption features of unknown origin found in the spectra of stars viewed through one or several clouds of the interstellar medium (ISM). Research of DIBs outside the Milky Way is currently very limited. In particular, spatially resolved investigations of DIBs outside of the Local Group are, to our knowledge, inexistent. Aims. In this contribution, we explore the capability of the high-sensitivity integral field spectrograph, MUSE, as a tool for mapping diffuse interstellar bands at distances larger than 100 Mpc. Methods. We used MUSE commissioning data for AM1353-272 B, the member with the highest extinction of the Dentist's Chair, an interacting system of two spiral galaxies. High signal-to-noise spectra were created by co-adding the signal of many spatial elements distributed in a geometry of concentric elliptical half-rings. Results. We derived decreasing radial profiles for the equivalent width of the lambda 5780.5 DIB both in the receding and approaching side of the companion galaxy up to distances of similar to 4.6 kpc from the centre of the galaxy. The interstellar extinction as derived from the Ha/H beta line ratio displays a similar trend, with decreasing values towards the external parts. This translates into an intrinsic correlation between the strength of the DIB and the extinction within AM1353-272 B, consistent with the currently existing global trend between these quantities when using measurements for Galactic and extragalactic sightlines. Conclusions. It seems feasible to map the DIB strength in the Local Universe, which has up to now only been performed for the Milky Way. This offers a new approach to studying the relationship between DIBs and other characteristics and species of the ISM in addition to using galaxies in the Local Group or sightlines towards very bright targets outside the Local Group.}, language = {en} } @article{WendtMolaro2012, author = {Wendt, Martin and Molaro, P.}, title = {QSO 0347-383 and the invariance of m(p)/m(e) in the course of cosmic time}, series = {Astronomy and astrophysics : an international weekly journal}, volume = {541}, journal = {Astronomy and astrophysics : an international weekly journal}, number = {3}, publisher = {EDP Sciences}, address = {Les Ulis}, issn = {0004-6361}, doi = {10.1051/0004-6361/201218862}, pages = {8}, year = {2012}, abstract = {Context. The variation of the dimensionless fundamental physical constant mu = m(p)/m(e) - the proton to electron mass ratio - can be constrained via observation of Lyman and Werner lines of molecular hydrogen in the spectra of damped Lyman alpha systems (DLAs) in the line of sight to distant QSOs. Aims. Our intention is to maximize the possible precision of quasar absorption spectroscopy with regard to the investigation of the variation of the proton-to-electron mass-ratio mu. The demand for precision requires an understanding of the errors involved and effective techniques to handle present systematic errors. Methods. An analysis based on UVES high resolution data sets of QSO 0347-383 and its DLA is put forward and new approaches to some of the steps involved in the data analysis are introduced. We apply corrections for the observed offsets between discrete spectra and for the first time we find indications for inter-order distortions. Results. Drawing on VLT-UVES observations of QSO 0347-383 in 2009 our analysis yields Delta mu/mu = (4.3 +/- 7.2) x 10(-6) at z(abs) = 3.025. Conclusions. Current analyzes tend to underestimate the impact of systematic errors. Based on the scatter of the measured redshifts and the corresponding low significance of the redshift-sensitivity correlation we estimate the limit of accuracy of line position measurements to similar to 220 m s (1), consisting of roughly 150 m s (1) due to the uncertainty of the absorption line fit and about 150 m s (1) allocated to systematics related to instrumentation and calibration.}, language = {en} } @article{WeilbacherMonrealIberoKollatschnyetal.2015, author = {Weilbacher, Peter Michael and Monreal-Ibero, Ana and Kollatschny, Wolfram and Ginsburg, Adam and McLeod, Anna F. and Kamann, Sebastian and Sandin, Christer and Palsa, Ralf and Wisotzki, Lutz and Bacon, Roland and Selman, Fernando and Brinchmann, Jarle and Caruana, Joseph and Kelz, Andreas and Martinsson, Thomas and Pecontal-Rousset, Arlette and Richard, Johan and Wendt, Martin}, title = {A MUSE map of the central Orion Nebula (M 42)}, series = {Astronomy and astrophysics : an international weekly journal}, volume = {582}, journal = {Astronomy and astrophysics : an international weekly journal}, publisher = {EDP Sciences}, address = {Les Ulis}, issn = {1432-0746}, doi = {10.1051/0004-6361/201526529}, pages = {16}, year = {2015}, abstract = {We present a new integral field spectroscopic dataset of the central part of the Orion Nebula (M 42), observed with the MUSE instrument at the ESO VLT. We reduced the data with the public MUSE pipeline. The output products are two FITS cubes with a spatial size of similar to 5'9 x 4'9 (corresponding to similar to 0.76 x 0.63 pc(2)) and a contiguous wavelength coverage of 4595 ... 9366 angstrom, spatially sampled at 0 ''.2. We provide two versions with a sampling of 1.25 angstrom and 0.85 angstrom in dispersion direction. Together with variance cubes these files have a size of 75 and 110 GiB on disk. They are the largest integral field mosaics to date in terms of information content. We make them available for use in the community. To validate this dataset, we compare world coordinates, reconstructed magnitudes, velocities, and absolute and relative emission line fluxes to the literature values and find excellent agreement. We derive a 2D map of extinction and present de-reddened flux maps of several individual emission lines and of diagnostic line ratios. We estimate physical properties of the Orion Nebula, using the emission line ratios [N II] and [S III] (for the electron temperature T-e) and [S II] and [Cl III] (for the electron density N-e), and show 2D images of the velocity measured from several bright emission lines.}, language = {en} } @article{Wendt2014, author = {Wendt, Martin}, title = {Constraints on variations of m(p)/m(e) based on UVES observations of H-2}, series = {Astronomische Nachrichten = Astronomical notes}, volume = {335}, journal = {Astronomische Nachrichten = Astronomical notes}, number = {1}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0004-6337}, doi = {10.1002/asna.201312008}, pages = {106 -- 112}, year = {2014}, abstract = {This article summarizes the latest results on the proton-to-electron mass ratio derived from H-2 observations at high redshift in the light of possible variations of fundamental physical constants. The focus lies on UVES observations of the past years as enormous progress was achieved since the first positive results on / were published. With the better understanding of systematics, dedicated observation runs, and numerous approaches to improve wavelength calibration accuracy, all current findings are in reasonable good agreement with no variation and provide an upper limit of / < 1 x 10(-5) for the redshift range of 2 < z < 3. ((}, language = {en} } @article{TurnerSchayeCrainetal.2016, author = {Turner, Monica L. and Schaye, Joop and Crain, Robert A. and Theuns, Tom and Wendt, Martin}, title = {Observations of metals in the z approximate to 3.5 intergalactic medium and comparison to the EAGLE simulations}, series = {Monthly notices of the Royal Astronomical Society}, volume = {462}, journal = {Monthly notices of the Royal Astronomical Society}, publisher = {Oxford Univ. Press}, address = {Oxford}, issn = {0035-8711}, doi = {10.1093/mnras/stw1816}, pages = {2440 -- 2464}, year = {2016}, abstract = {We study the z approximate to 3.5 intergalactic medium (IGM) by comparing new, high-quality absorption spectra of eight QSOs with < z(QSO)> = 3.75, to virtual observations of the Evolution and Assembly of Galaxies and their Environments (EAGLE) cosmological hydrodynamical simulations. We employ the pixel optical depth method and uncover strong correlations between various combinations of H I, C III, C IV, Si III, Si IV, and O VI. We find good agreement between many of the simulated and observed correlations, including tau(O) (VI) (tau(H) (I)). However, the observed median optical depths for the tau(C) (IV) (tau(H) (I)) and tau(Si) (IV) (tau(H) (I)) relations are higher than those measured from the mock spectra. The discrepancy increases from up to approximate to 0.1 dex at tau(H) (I) = 1 to approximate to 1 dex at tau(H) (I) = 10(2), where we are likely probing dense regions at small galactocentric distances. As possible solutions, we invoke (a) models of ionizing radiation softened above 4 Ryd to account for delayed completion of He II reionization; (b) simulations run at higher resolution; (c) the inclusion of additional line broadening due to unresolved turbulence; and (d) increased elemental abundances; however, none of these factors can fully explain the observed differences. Enhanced photoionization of H I by local sources, which was not modelled, could offer a solution. However, the much better agreement with the observed O VI(H I) relation, which we find probes a hot and likely collisionally ionized gas phase, indicates that the simulations are not in tension with the hot phase of the IGM, and suggests that the simulated outflows may entrain insufficient cool gas.}, language = {en} } @article{KamannHusserBrinchmannetal.2016, author = {Kamann, S. and Husser, T. -O. and Brinchmann, Jarle and Emsellem, E. and Weilbacher, Peter Michael and Wisotzki, Lutz and Wendt, Martin and Krajnovic, D. and Roth, M. M. and Bacon, Roland and Dreizler, S.}, title = {MUSE crowded field 3D spectroscopy of over 12 000 stars in the globular cluster NGC 6397}, series = {Tectonophysics : international journal of geotectonics and the geology and physics of the interior of the earth}, volume = {588}, journal = {Tectonophysics : international journal of geotectonics and the geology and physics of the interior of the earth}, publisher = {EDP Sciences}, address = {Les Ulis}, issn = {1432-0746}, doi = {10.1051/0004-6361/201527065}, pages = {12}, year = {2016}, abstract = {We present a detailed analysis of the kinematics of the Galactic globular cluster NGC 6397 based on more than similar to 18 000 spectra obtained with the novel integral field spectrograph MUSE. While NGC 6397 is often considered a core collapse cluster, our analysis suggests a flattening of the surface brightness profile at the smallest radii. Although it is among the nearest globular clusters, the low velocity dispersion of NGC 6397 of < 5 km s(-1) imposes heavy demands on the quality of the kinematical data. We show that despite its limited spectral resolution, MUSE reaches an accuracy of 1 km s(-1) in the analysis of stellar spectra. We find slight evidence for a rotational component in the cluster and the velocity dispersion profile that we obtain shows a mild central cusp. To investigate the nature of this feature, we calculate spherical Jeans models and compare these models to our kinematical data. This comparison shows that if a constant mass-to-light ratio is assumed, the addition of an intermediate-mass black hole with a mass of 600 M-circle dot brings the model predictions into agreement with our data, and therefore could be at the origin of the velocity dispersion profile. We further investigate cases with varying mass-to-light ratios and find that a compact dark stellar component can also explain our observations. However, such a component would closely resemble the black hole from the constant mass-to-light ratio models as this component must be confined to the central similar to 5 ' of the cluster and must have a similar mass. Independent constraints on the distribution of stellar remnants in the cluster or kinematic measurements at the highest possible spatial resolution should be able to distinguish the two alternatives.}, language = {en} } @article{WendtHusserKamannetal.2017, author = {Wendt, Martin and Husser, Tim-Oliver and Kamann, Sebastian and Monreal-Ibero, Ana and Richter, Philipp and Brinchmann, Jarle and Dreizler, Stefan and Weilbacher, Peter Michael and Wisotzki, Lutz}, title = {Mapping diffuse interstellar bands in the local ISM on small scales via MUSE 3D spectroscopy A pilot study based on globular cluster NGC 6397}, series = {Astronomy and astrophysics : an international weekly journal}, volume = {607}, journal = {Astronomy and astrophysics : an international weekly journal}, publisher = {EDP Sciences}, address = {Les Ulis}, issn = {1432-0746}, doi = {10.1051/0004-6361/201629816}, pages = {16}, year = {2017}, abstract = {Context. We map the interstellar medium (ISM) including the diffuse interstellar bands (DIBs) in absorption toward the globular cluster NGC6397 using VLT/MUSE. Assuming the absorbers are located at the rim of the Local Bubble we trace structures on the order of mpc (milliparsec, a few thousand AU). Aims. We aimed to demonstrate the feasibility to map variations of DIBs on small scales with MUSE. The sightlines defined by binned stellar spectra are separated by only a few arcseconds and we probe the absorption within a physically connected region. Methods. This analysis utilized the fitting residuals of individual stellar spectra of NGC6397 member stars and analyzed lines from neutral species and several DIBs in Voronoi-binned composite spectra with high signal-to-noise ratio (S/N). Results. This pilot study demonstrates the power of MUSE for mapping the local ISM on very small scales which provides a new window for ISM observations. We detect small scale variations in Na-I and K-I as well as in several DIBs within few arcseconds, or mpc with regard to the Local Bubble. We verify the suitability of the MUSE 3D spectrograph for such measurements and gain new insights by probing a single physical absorber with multiple sight lines.}, language = {en} } @article{FinleyBoucheContinietal.2017, author = {Finley, Hayley and Bouche, Nicolas and Contini, Thierry and Epinat, Benoit and Bacon, Roland and Brinchmann, Jarle and Cantalupo, Sebastiano and Erroz-Ferrer, Santiago and Marino, Aella Anna and Maseda, Michael and Richard, Johan and Schroetter, Ilane and Verhamme, Anne and Weilbacher, Peter Michael and Wendt, Martin and Wisotzki, Lutz}, title = {Galactic winds with MUSE: A direct detection of Fe II* emission from a z=1.29 galaxy}, series = {Astronomy and astrophysics : an international weekly journal}, volume = {605}, journal = {Astronomy and astrophysics : an international weekly journal}, publisher = {EDP Sciences}, address = {Les Ulis}, issn = {1432-0746}, doi = {10.1051/0004-6361/201730428}, pages = {15}, year = {2017}, abstract = {Emission signatures from galactic winds provide an opportunity to directly map the outflowing gas, but this is traditionally challenging because of the low surface brightness. Using very deep observations (27 h) of the Hubble Deep Field South with the Multi Unit Spectroscopic Explorer (MUSE) instrument, we identify signatures of an outflow in both emission and absorption from a spatially resolved galaxy at z = 1.29 with a stellar mass M-star = 8 x 10(9) M-circle dot, star formation rate SFR = 77(-25)(+40) M-circle dot yr(-1), and star formation rate surface brightness Sigma(SFR) = 1.6 M-circle dot kpc(-2) within the [OII] lambda lambda 3727, 3729 half-light radius R-1/2, ([OII]) = 2.76 +/- 0.17 kpc. From a component of the strong resonant Mg II and Fe II absorptions at -350 km s(-1), we infer a mass outflow rate that is comparable to the star formation rate. We detect non-resonant Fe II* emission, at lambda 2365, lambda 2396, lambda 2612, and lambda 2626, at 1.2-2.4-1.5-2.7 x 10-(18) erg s(-1) cm(-2) respectively. The flux ratios are consistent with the expectations for optically thick gas. By combining the four non-resonant Fe II* emission lines, we spatially map the Fe II* emission from an individual galaxy for the first time. The Fe II* emission has an elliptical morphology that is roughly aligned with the galaxy minor kinematic axis, and its integrated half-light radius, R-1/2, (Fe II*) = 4.1 +/- 0.4 kpc, is 70\% larger than the stellar continuum (R-1/2,(star) similar or equal to 2.34 +/- 0.17) or the [O II] nebular line. Moreover, the Fe II* emission shows a blue wing extending up to -400 km s(-1), which is more pronounced along the galaxy minor kinematic axis and reveals a C-shaped pattern in a p - v diagram along that axis. These features are consistent with a bi-conical outflow.}, language = {en} } @article{WendtBoucheZabletal.2021, author = {Wendt, Martin and Bouche, Nicolas F. and Zabl, Johannes and Schroetter, Ilane and Muzahid, Sowgat}, title = {MusE GAs FLOw and Wind V. The dust/metallicity-anisotropy of the circum-galactic medium}, series = {Monthly notices of the Royal Astronomical Society}, volume = {502}, journal = {Monthly notices of the Royal Astronomical Society}, number = {3}, publisher = {Oxford Univ. Press}, address = {Oxford}, issn = {0035-8711}, doi = {10.1093/mnras/stab049}, pages = {3733 -- 3745}, year = {2021}, abstract = {We investigate whether the dust content of the circum-galactic medium (CGM) depends on the location of the quasar sightline with respect to the galaxy major-axis using 13 galaxy-Mg II absorber pairs (9-81 kpc distance) from the MusE GAs FLOw and Wind (MEGAFLOW) survey at 0.4 < z < 1.4. The dust content of the CGM is obtained from [Zn/Fe] using ultraviolet and visual echelle spectrograph data. When a direct measurement of [Zn/Fe] is unavailable, we estimate the dust depletion from a method that consists in solving for the depletion from multiple singly ionized ions (e.g. Mn II, Cr II, and Zn II) since each ion depletes on dust grains at different rates. We find a positive correlation between the azimuthal angle and [Zn/Fe] with a Pearson's gamma = 0.70 +/- 0.14. The sightlines along the major axis show [Zn/Fe] < 0.5, whereas the [Zn/Fe] is > 0.8 along the minor axis. These results suggest that the CGM along the minor axis is on average more metal enriched (by approximate to 1 dex) than the gas located along the major axis of galaxies provided that dust depletion is a proxy for metallicity. This anisotropic distribution is consistent with recent results on outflow and accretion in hydro-dynamical simulations.}, language = {en} } @article{SchroetterBoucheWendtetal.2016, author = {Schroetter, I. and Bouche, Nicolas and Wendt, Martin and Contini, Thierry and Finley, H. and Pello, R. and Bacon, Roland and Cantalupo, Sebastiano and Marino, Raffaella Anna and Richard, J. and Lilly, S. J. and Schaye, Joop and Soto, K. and Steinmetz, Matthias and Straka, Lorrie A. and Wisotzki, Lutz}, title = {MUSE GAS FLOW AND WIND (MEGAFLOW). I. FIRST MUSE RESULTS ON BACKGROUND QUASARS}, series = {The astrophysical journal : an international review of spectroscopy and astronomical physics}, volume = {833}, journal = {The astrophysical journal : an international review of spectroscopy and astronomical physics}, publisher = {IOP Publ. Ltd.}, address = {Bristol}, issn = {0004-637X}, doi = {10.3847/1538-4357/833/1/39}, pages = {17}, year = {2016}, abstract = {The physical properties of galactic winds are one of the keys to understand galaxy formation and evolution. These properties can be constrained thanks to background quasar lines of sight (LOS) passing near star-forming galaxies (SFGs). We present the first results of the MusE GAs FLOw and Wind survey obtained from two quasar fields, which have eight Mg II absorbers of which three have rest equivalent width greater than 0.8 angstrom. With the new Multi Unit Spectroscopic Explorer (MUSE) spectrograph on the Very Large Telescope (VLT), we detect six (75\%) Mg II host galaxy candidates within a radius of 30. from the quasar LOS. Out of these six galaxy-quasar pairs, from geometrical argument, one is likely probing galactic outflows, where two are classified as "ambiguous,"two are likely probing extended gaseous disks and one pair seems to be a merger. We focus on the wind-pair and constrain the outflow using a high-resolution quasar spectra from the Ultraviolet and Visual Echelle Spectrograph. Assuming the metal absorption to be due to ga;s flowing out of the detected galaxy through a cone along the minor axis, we find outflow velocities in the order of approximate to 150 km s(-1) (i.e., smaller than the escape velocity) with a loading factor, eta = M-out/SFR, of approximate to 0.7. We see evidence for an open conical flow, with a low-density inner core. In the future, MUSE will provide us with about 80 multiple galaxy-quasar pairs in two dozen fields.}, language = {en} } @article{WisotzkiBaconBrinchmannetal.2018, author = {Wisotzki, Lutz and Bacon, R. and Brinchmann, J. and Cantalupo, S. and Richter, Philipp and Schaye, J. and Schmidt, Kasper Borello and Urrutia, Tanya and Weilbacher, Peter Michael and Akhlaghi, M. and Bouche, N. and Contini, T. and Guiderdoni, B. and Herenz, E. C. and Inami, H. and Kerutt, Josephine Victoria and Leclercq, F. and Marino, R. A. and Maseda, M. and Monreal-Ibero, A. and Nanayakkara, T. and Richard, J. and Saust, R. and Steinmetz, Matthias and Wendt, Martin}, title = {Nearly all the sky is covered by Lyman-alpha emission around high-redshift galaxies}, series = {Nature : the international weekly journal of science}, volume = {562}, journal = {Nature : the international weekly journal of science}, number = {7726}, publisher = {Nature Publ. Group}, address = {London}, issn = {0028-0836}, doi = {10.1038/s41586-018-0564-6}, pages = {229 -- 232}, year = {2018}, abstract = {Galaxies are surrounded by large reservoirs of gas, mostly hydrogen, that are fed by inflows from the intergalactic medium and by outflows from galactic winds. Absorption-line measurements along the lines of sight to bright and rare background quasars indicate that this circumgalactic medium extends far beyond the starlight seen in galaxies, but very little is known about its spatial distribution. The Lyman-alpha transition of atomic hydrogen at a wavelength of 121.6 nanometres is an important tracer of warm (about 104 kelvin) gas in and around galaxies, especially at cosmological redshifts greater than about 1.6 at which the spectral line becomes observable from the ground. Tracing cosmic hydrogen through its Lyman-a emission has been a long-standing goal of observational astrophysics(1-3), but the extremely low surface brightness of the spatially extended emission is a formidable obstacle. A new window into circumgalactic environments was recently opened by the discovery of ubiquitous extended Lyman-alpha emission from hydrogen around high-redshift galaxies(4,5). Such measurements were previously limited to especially favourable systems(6-8) or to the use of massive statistical averaging(9,10) because of the faintness of this emission. Here we report observations of low-surface-brightness Lyman-alpha emission surrounding faint galaxies at redshifts between 3 and 6. We find that the projected sky coverage approaches 100 per cent. The corresponding rate of incidence (the mean number of Lyman-alpha emitters penetrated by any arbitrary line of sight) is well above unity and similar to the incidence rate of high-column-density absorbers frequently detected in the spectra of distant quasars(11-14). This similarity suggests that most circumgalactic atomic hydrogen at these redshifts has now been detected in emission.}, language = {en} } @article{RichterNuzaFoxetal.2017, author = {Richter, Philipp and Nuza, S. E. and Fox, Andrew J. and Wakker, Bart P. and Lehner, N. and Ben Bekhti, Nadya and Fechner, Cora and Wendt, Martin and Howk, J. Christopher and Muzahid, S. and Ganguly, R. and Charlton, Jane C.}, title = {An HST/COS legacy survey of high-velocity ultraviolet absorption in the}, series = {Astronomy and astrophysics : an international weekly journal}, volume = {607}, journal = {Astronomy and astrophysics : an international weekly journal}, publisher = {EDP Sciences}, address = {Les Ulis}, issn = {1432-0746}, doi = {10.1051/0004-6361/201630081}, pages = {90}, year = {2017}, abstract = {Context. The Milky Way is surrounded by large amounts of diffuse gaseous matter that connects the stellar body of our Galaxy with its large-scale Local Group (LG) environment. Aims. To characterize the absorption properties of this circumgalactic medium (CGM) and its relation to the LG we present the so-far largest survey of metal absorption in Galactic high-velocity clouds (HVCs) using archival ultraviolet (UV) spectra of extragalactic background sources. The UV data are obtained with the Cosmic Origins Spectrograph (COS) onboard the Hubble Space Telescope (HST) and are supplemented by 21 cm radio observations of neutral hydrogen. Methods. Along 270 sightlines we measure metal absorption in the lines of Si II, Si III, C II, and C IV and associated H I 21 cm emission in HVCs in the velocity range vertical bar v(LSR)vertical bar = 100-500 km s(-1). With this unprecedented large HVC sample we were able to improve the statistics on HVC covering fractions, ionization conditions, small-scale structure, CGM mass, and inflow rate. For the first time, we determine robustly the angular two point correlation function of the high-velocity absorbers, systematically analyze antipodal sightlines on the celestial sphere, and compare the HVC absorption characteristics with that of damped Lyman alpha absorbers (DLAs) and constrained cosmological simulations of the LG (CLUES project).}, language = {en} } @article{WendtKulanekVargaetal.2022, author = {Wendt, Martin and Kulanek, Dustin and Varga, Zoltan and Rakosy, Laszlo and Schmitt, Thomas}, title = {Pronounced mito-nuclear discordance and various Wolbachia infections in the water ringlet Erebia pronoe have resulted in a complex phylogeographic structure}, series = {Scientific reports}, volume = {12}, journal = {Scientific reports}, number = {1}, publisher = {Nature Portfolio}, address = {Berlin}, issn = {2045-2322}, doi = {10.1038/s41598-022-08885-8}, pages = {10}, year = {2022}, abstract = {Several morphological and mitochondrial lineages of the alpine ringlet butterfly species Erebia pronoe have been described, indicating a complex phylogenetic structure. However, the existing data were insufficient and allow neither a reconstruction of the biogeographic history, nor an assessment of the genetic lineages. Therefore, we analysed mitochondrial (COI, NDI) and nuclear (EF1 alpha, RPS5) gene sequences and compared them with sequences from the sister species Erebia melas. Additionally, we combined this information with morphometric data of the male genitalia and the infection patterns with Wolbachia strains, based on a WSP analysis. We obtained a distinct phylogeographic structure within the E. pronoe-melas complex with eight well-distinguishable geographic groups, but also a remarkable mito-nuclear discordance. The mito-nuclear discordance in E. melas and E. pronoe glottis can be explained by different ages of Wolbachia infections with different Wolbachia strains, associated selective sweeps, and hybridisation inhibition. Additionally, we found indications for incipient speciation of E. pronoe glottis in the Pyrenees and a pronounced range dynamic within and among the other high mountain systems of Europe. Our results emphasize the importance of combined approaches in reconstructing biogeographic patterns and evaluating phylogeographic splits.}, language = {en} } @article{WendtSenftlebenGrosetal.2021, author = {Wendt, Martin and Senftleben, Nele and Gros, Patrick and Schmitt, Thomas}, title = {Coping with environmental extremes}, series = {Insects : open access journal}, volume = {12}, journal = {Insects : open access journal}, number = {10}, publisher = {MDPI}, address = {Basel}, issn = {2075-4450}, doi = {10.3390/insects12100896}, pages = {12}, year = {2021}, abstract = {Simple Summary:\& nbsp;High alpine meadows are home to numerous endemic butterfly species. A combination of climate change and changes in agricultural practices has led to a severe decline in many species. A seemingly unaffected representative of this habitat is Erebia pronoe. We studied the behaviour, resource use and population structure of this species to explain its resilience and estimate its future survival potential. This species shows pronounced protandry in combination with serial eclosion. Males were significantly more active and mobile and were also caught significantly more often than females, resulting in a pronounced shift in sex ratio in the predicted population structure. The adults use a wide range of nectar plants and establish homeranges in areas of high habitat quality. Thus, Erebia pronoe adults use a wide array of resources combined with a slight specialisation to avoid niche overlap with closely related species. The resulting ecological flexibility seems to be an adaptation to unpredictable environmental conditions, which should be the result of a long-lasting adaptation process. Moreover, the combination of opportunism and modest specialisation should also be a good basis for coping with future changes caused by climate and land-use change.




A mark-recapture study of the nominotypical Erebia pronoe in the Alps was conducted to survey its ecological demands and characteristics. Population structure analysis revealed a combination of protandry (one-week earlier eclosion of males) and serial eclosion. Significant differences between both sexes were found in population density (males: 580/ha \& PLUSMN; 37 SE; females: 241/ha \& PLUSMN; 66 SE), sex-ratio (2.4) and behaviour (57.7 vs. 11.9\% flying). Both sexes used a wide range of nectar plants (Asteraceae, 77.3\%; Dipsacaceae, 12.3\%; Gentianaceae, 9.7\%). The use of nectar plants shows a non-specific spectrum, which, however, completely avoids overlap with the locally co-occurring species Erebia nivalis. Movement patterns show the establishment of homeranges, which significantly limits the migration potential. Due to its broad ecological niche, E. pronoe will probably be able to react plastically to the consequences of climate change. The formation of high population densities, the unconcerned endangerment status, the unspecific resource spectrum and the sedentary character of the species make E. pronoe a potential indicator of the quality and general resource occurrence of alpine rupicolous grasslands.}, language = {en} }