TY - JOUR A1 - Paalvast, M. A1 - Verhamme, A. A1 - Straka, L. A. A1 - Brinchmann, J. A1 - Herenz, Edmund Christian A1 - Carton, D. A1 - Gunawardhana, M. L. P. A1 - Boogaard, L. A. A1 - Cantalupo, S. A1 - Contini, T. A1 - Epinat, Benoit A1 - Inami, H. A1 - Marino, R. A. A1 - Maseda, M. V. A1 - Michel-Dansac, L. A1 - Muzahid, S. A1 - Nanayakkara, T. A1 - Pezzulli, Gabriele A1 - Richard, J. A1 - Schaye, Joop A1 - Segers, M. C. A1 - Urrutia, Tanya A1 - Wendt, Martin A1 - Wisotzki, Lutz T1 - Properties and redshift evolution of star-forming galaxies with high [0 III]/[O II] ratios with MUSE at 0.28 < z < 0.85 JF - Astronomy and astrophysics : an international weekly journal N2 - 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. KW - galaxies: evolution KW - galaxies: ISM KW - galaxies: abundances KW - ISM: structure KW - ISM: kinematics and dynamics KW - dark ages, reionization, first stars Y1 - 2018 U6 - https://doi.org/10.1051/0004-6361/201832866 SN - 0004-6361 SN - 1432-0746 VL - 618 PB - EDP Sciences CY - Les Ulis ER - TY - JOUR A1 - Finley, Hayley A1 - Bouche, Nicolas A1 - Contini, Thierry A1 - Epinat, Benoit A1 - Bacon, Roland A1 - Brinchmann, Jarle A1 - Cantalupo, Sebastiano A1 - Erroz-Ferrer, Santiago A1 - Marino, Aella Anna A1 - Maseda, Michael A1 - Richard, Johan A1 - Schroetter, Ilane A1 - Verhamme, Anne A1 - Weilbacher, Peter Michael A1 - Wendt, Martin A1 - Wisotzki, Lutz T1 - Galactic winds with MUSE: A direct detection of Fe II* emission from a z=1.29 galaxy JF - Astronomy and astrophysics : an international weekly journal N2 - 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. KW - galaxies: evolution KW - galaxies: formation KW - galaxies: starburst KW - galaxies: ISM KW - ISM: jets and outflows KW - ultraviolet: ISM Y1 - 2017 U6 - https://doi.org/10.1051/0004-6361/201730428 SN - 1432-0746 VL - 605 PB - EDP Sciences CY - Les Ulis ER - TY - JOUR A1 - Bouche, Nicolas A1 - Finley, H. A1 - Schroetter, I. A1 - Murphy, M. T. A1 - Richter, Philipp A1 - Bacon, Roland A1 - Contini, Thierry A1 - Richard, J. A1 - Wendt, Martin A1 - Kamann, S. A1 - Epinat, Benoit A1 - Cantalupo, Sebastiano A1 - Straka, Lorrie A. A1 - Schaye, Joop A1 - Martin, C. L. A1 - Peroux, C. A1 - Wisotzki, Lutz A1 - Soto, K. A1 - Lilly, S. A1 - Carollo, C. M. A1 - Brinchmann, Jarle A1 - Kollatschny, W. T1 - POSSIBLE SIGNATURES OF A COLD-FLOW DISK FROM MUSE USING A z similar to 1 GALAXY-QUASAR PAIR TOWARD SDSS J1422-0001 JF - The astrophysical journal : an international review of spectroscopy and astronomical physics N2 - 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. KW - galaxies: evolution KW - galaxies: formation KW - intergalactic medium KW - quasars: individual (SDSS J142253.31-000149) Y1 - 2016 U6 - https://doi.org/10.3847/0004-637X/820/2/121 SN - 0004-637X SN - 1538-4357 VL - 820 SP - 1872 EP - 1882 PB - IOP Publ. Ltd. CY - Bristol ER -