@book{BauerHajaschLuebkingetal.2017, author = {Bauer, Hartmut and Hajasch, Lydia and L{\"u}bking, Uwe and Stein, Ursula and Roth, Roland and Sippel, Hanns-J{\"o}rg and Bock, Stephanie and Friesecke, Frank and Kleger, Heinz and Vowe, Gerhard and Utz, Stephanie Sophia and Buchmann, Madeleine and L{\"o}ffler, Roland and Zielske, Johanna}, title = {Partizipation in der B{\"u}rgerkommune}, series = {KWI Schriften}, journal = {KWI Schriften}, number = {10}, editor = {Bauer, Hartmut and B{\"u}chner, Christiane and Hajasch, Lydia}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, isbn = {978-3-86956-371-8}, issn = {1867-951X}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-101601}, publisher = {Universit{\"a}t Potsdam}, pages = {214}, year = {2017}, abstract = {Konzepte, nach denen sich die demokratische Mitwirkung der B{\"u}rger vornehmlich in Wahlen ersch{\"o}pft, geh{\"o}ren sp{\"a}testens seit „Stuttgart 21" der Vergangenheit an. Indes ist die B{\"u}rgerbeteiligung auch jenseits solcher Großprojekte l{\"a}ngst zu einem beherrschenden Thema der Zeit herangewachsen. Das gilt zumal f{\"u}r die kommunale Ebene. Dort werden traditionsreiche Partizipationsformen nicht nur intensiv genutzt, sondern zunehmend um neue Beteiligungsvarianten erg{\"a}nzt und in innovativen Modellprojekten fortentwickelt. Dabei treten zwei Antriebskr{\"a}fte besonders hervor. Zum einen fordern die B{\"u}rger nach den Maximen „Mitmachen, Mitwirken, Mitentscheiden" deutlich verbesserte Partizipationsm{\"o}glichkeiten ein. Zum anderen setzen die Kommunen verst{\"a}rkt auf b{\"u}rgerschaftliches Engagement zur Erschließung Ressourcen privater Akteure f{\"u}r die Bereitstellung {\"o}ffentlicher Leistungen. {\"U}bergreifende Perspektive ist die Ausbildung einer Neuen Partizipationskultur in der B{\"u}rgerkommune zur Optimierung des Gemeinwohls. F{\"u}r die kommunale Praxis ist das partizipationsgest{\"u}tzte Miteinander von Verwaltung. Politik und B{\"u}rgerschaft in Systementw{\"u}rfen, Leitbildern, Organisations- und Verfahrensmodellen sowie lokalen Beteiligungsformaten konkretisiert. Doch verbinden sich mit den alten und neuen Ans{\"a}tzen der B{\"u}rgerbeteiligung noch eine ganze Reihe offener Fragen - so etwa nach den rechtlichen M{\"o}glichkeiten und Grenzen der neuen kommunalen Beteiligungskultur, nach Erfolgsbedingungen und konkreten Erfahrungen mit der Umsetzung von Partizipationsmodellen. Auf der 21. Fachtagung des Kommunalwissenschaftlichen Instituts (KWI) der Universit{\"a}t Potsdam wurden Schl{\"u}sselthemen der Neuen Partizipationskultur in der B{\"u}rgerkommune, namentlich der normativen Rahmenbedingungen und politischen Direktiven, Modernisierungsimpulse und Aktivierungsstrategien, Erfolgsbedingungen und spezifische Problemlagen einschließlich der Fallstricke in der Praxis und nicht zuletzt ausgew{\"a}hlter Einsatzfelder mit den dazugeh{\"o}rigen Erfahrungen diskutiert.}, language = {de} } @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{Roth2017, author = {Roth, Roland}, title = {B{\"u}rgerpartizipation}, series = {Partizipation in der B{\"u}rgerkommune (KWI Schriften)}, journal = {Partizipation in der B{\"u}rgerkommune (KWI Schriften)}, number = {10}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, isbn = {978-3-86956-371-8}, issn = {1867-951X}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-104743}, pages = {57 -- 79}, year = {2017}, language = {de} } @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{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{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} }