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72 results on '"Soucail, G."'

1. Gender and Precarity in Astronomy

Author

Webb, N.A, Bot, C, Charpinet, S, Contini, T, Jouve, L, Meheut, H, Mei, S, Mosser, B, Soucail, G, Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Observatoire astronomique de Strasbourg (ObAS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Astrophysique Relativiste Théories Expériences Métrologie Instrumentation Signaux (ARTEMIS), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)

Subjects
[PHYS]Physics [physics], High Energy Astrophysical Phenomena (astro-ph.HE), Physics - Physics and Society, FOS: Physical sciences, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Physics and Society (physics.soc-ph), [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, Instrumentation and Methods for Astrophysics (astro-ph.IM)
Abstract

Following the survey Well-being in astrophysics that was sent out in March 2021, to establish how astrophysics researchers, primarily in France, experience their career, some of the results were published in Webb et al. (2021). Here we further analyse the data to determine if gender can cause different experiences in astrophysics. We also study the impact on the well-being of temporary staff (primarily PhD students and postdocs), compared to permanent staff. Whilst more temporary staff stated that they felt permanently overwhelmed than permanent staff, the experiences in astrophysics for the different genders were in general very similar, except in one area. More than three times more females than males experienced harassment or discrimination, rising sharply for gender discrimination and sexual harassment, where all of those having experienced sexual harassment and who had provided their gender in the survey, were female. Further, as previously reported (Webb et al. 2021), 20% of the respondents had suffered mental health issues before starting their career in astrophysics. We found that whilst this group was split approximately equally with regards to males and females, the number rose sharply to almost 45% of astronomers experiencing mental health issues since starting in astrophysics. Of this population, there were 50% more females than males. This excess of females was almost entirely made up of the population of women that had been harassed or discriminated against., 5 pages, 1 figure, published in the SF2A-2022: Proceedings of the Annual meeting of the French Society of Astronomy and Astrophysics. Eds.: J. Richard, A. Siebert, E. Lagadec, N. Lagarde, O. Venot, J. Malzac, J.-B. Marquette, M. N'Diaye, D. Briot, pp.171-175

Published
2023

3. The X-CLASS survey: A catalogue of 1646 X-ray-selected galaxy clusters up to z$\sim$1.5

Author

Koulouridis, E., Clerc, N., Sadibekova, T., Chira, M., Drigga, E., Faccioli, L., Fèvre, J.P. Le, Garrel, C., Gaynullina, E., Gkini, A., Kosiba, M., Pacaud, F., Pierre, M., Ridl, J., Tazhenova, K., Adami, C., Altieri, B., Baguley, J.-C., Cabanac, R., Cucchetti, E., Khalikova, A., Lieu, M., Melin, J.-B., Molham, M., Ramos-Ceja, M.E., Soucail, G., Takey, A., Valtchanov, I., Le Fèvre, J., Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing [Penteli] (IAASARS), National Observatory of Athens (NOA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Aristotle University of Thessaloniki, Ulugh Beg Astronomical Institute, Uzbekistan Academy of Sciences, Department of Astrophysics, Astronomy and Mechanics [Kapodistrian Univ], National and Kapodistrian University of Athens (NKUA), Masaryk University [Brno] (MUNI), Dipartimento di Fisica [Torino], Università degli studi di Torino (UNITO), Argelander Institute for Astronomy (AlfA), Rheinische Friedrich-Wilhelms-Universität Bonn, Max Planck Institute for Extraterrestrial Physics (MPE), Max-Planck-Gesellschaft, European Space Astronomy Centre (ESAC), European Space Agency (ESA), H. H. Wills Physics Laboratory [Bristol], University of Bristol [Bristol], School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), National Research Institute of Astronomy and Geophysics [Helwan] (NRIAG), Telespazio, Services par satellites, Operations Department (ESAC), European Space Agency (ESA)-European Space Agency (ESA), The Saclay team, Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Università degli studi di Torino = University of Turin (UNITO), Agence Spatiale Européenne = European Space Agency (ESA), and Agence Spatiale Européenne = European Space Agency (ESA)-Agence Spatiale Européenne = European Space Agency (ESA)

Subjects
Cosmology and Nongalactic Astrophysics (astro-ph.CO), media_common.quotation_subject, FOS: Physical sciences, Context (language use), Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, 0103 physical sciences, Cluster (physics), 010303 astronomy & astrophysics, Galaxy cluster, media_common, Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Redshift, Universe, Determining the number of clusters in a data set, Space and Planetary Science, Sky, Astrophysics of Galaxies (astro-ph.GA), Cluster sampling, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

Cosmological probes based on galaxy clusters rely on cluster number counts and large-scale structure information. X-ray cluster surveys are well suited for this purpose, since they are far less affected than optical surveys by projection effects, and cluster properties can be predicted with good accuracy. The XMM Cluster Archive Super Survey, X-CLASS, is a serendipitous search of X-ray-detected galaxy clusters in 4176 XMM-Newton archival observations until August 2015. All observations are clipped to exposure times of 10 and 20 ks to obtain uniformity and they span ~269 deg$^2$ across the high-Galactic latitude sky ($|b|> 20^o$). The main goal of the survey is the compilation of a well-selected cluster sample suitable for cosmological analyses. We describe the detection algorithm, the visual inspection, the verification process and the redshift validation of the cluster sample, as well as the cluster selection function computed by simulations. We also present the various metadata that are released with the catalogue, along with the redshifts of 124 clusters obtained with a dedicated multi-object spectroscopic follow-up programme. With this publication we release the new X-CLASS catalogue of 1646 well-selected X-ray-detected clusters over a wide sky area, along with their selection function. The sample spans a wide redshift range, from the local Universe up to z~1.5, with 982 spectroscopically confirmed clusters, and over 70 clusters above z=0.8. Because of its homogeneous selection and thorough verification, the cluster sample can be used for cosmological analyses, but also as a test-bed for the upcoming eROSITA observations and other current and future large-area cluster surveys. It is the first time that such a catalogue is made available to the community via an interactive database which gives access to a wealth of supplementary information, images, and data., Accepted for publication in A&A

Published
2021
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4. The X-CLASS survey: A catalogue of 1646 X-ray-selected galaxy clusters up to similar to 1.5

Author

Koulouridis, E. Clerc, N. Sadibekova, T. Chira, M. and Drigga, E. Faccioli, L. Le Fevre, J. P. Garrel, C. and Gaynullina, E. Gkini, A. Kosiba, M. Pacaud, F. Pierre, M. Ridl, J. Tazhenova, K. Adami, C. Altieri, B. and Baguley, J. -C. Cabanac, R. Cucchetti, E. Khalikova, A. and Lieu, M. Melin, J. -B. Molham, M. Ramos-Ceja, M. E. and Soucail, G. Takey, A. Valtchanov, I.

Subjects
Astrophysics::Cosmology and Extragalactic Astrophysics
Abstract

Context. Cosmological probes based on galaxy clusters rely on cluster number counts and large-scale structure information. X-ray cluster surveys are well suited for this purpose because they are far less affected by projection effects than optical surveys, and cluster properties can be predicted with good accuracy.Aims. The XMM Cluster Archive Super Survey, X-CLASS, is a serendipitous search of X-ray-detected galaxy clusters in 4176 XMM-Newton archival observations until August 2015. All observations are clipped to exposure times of 10 and 20 ks to obtain uniformity, and they span similar to 269 deg(2) across the high-Galactic latitude sky (|b| > 20 degrees). The main goal of the survey is the compilation of a well-selected cluster sample suitable for cosmological analyses.Methods. We describe the detection algorithm, the visual inspection, the verification process, and the redshift validation of the cluster sample, as well as the cluster selection function computed by simulations. We also present the various metadata that are released with the catalogue, along with two different count-rate measurements, an automatic one provided by the pipeline, and a more detailed and accurate interactive measurement. Furthermore, we provide the redshifts of 124 clusters obtained with a dedicated multi-object spectroscopic follow-up programme.Results. With this publication, we release the new X-CLASS catalogue of 1646 well-selected X-ray-detected clusters over a wide sky area, along with their selection function. The sample spans a wide redshift range, from the local Universe up to z similar to 1.5, with 982 spectroscopically confirmed clusters, and over 70 clusters above z=0.8. The redshift distribution peaks at z similar to 0.1, while if we remove the pointed observations it peaks at z similar to 0.3. Because of its homogeneous selection and thorough verification, the cluster sample can be used for cosmological analyses, but also as a test-bed for the upcoming eROSITA observations and other current and future large-area cluster surveys. It is the first time that such a catalogue is made available to the community via an interactive database which gives access to a wealth of supplementary information, images, and data.

Published
2021

5. VizieR Online Data Catalog: 12 massive lensing clusters MUSE observations (Richard+, 2021)

Author

Richard, J., Claeyssens, A., Lagattuta, D., Guaita, L., Bauer, F. E., Pello, R., Carton, D., Bacon, R., Soucail, G., Prieto Lyon, G., Kneib, J. -P., Mahler, G., Clement, B., Mercier, W., Variu, A., Tamone, A., Ebeling, H., Schmidt, K. B., Nanayakkara, T., Maseda, M., Weilbacher, P. M., Bouché, N., Bouwens, R. J., Wisotzki, L., La Vieuville, G., Martinez, J., Patricio, V., Service de réanimation médicale [CHU Rouen], Hôpital Charles Nicolle [Rouen], CHU Rouen, Normandie Université (NU)-Normandie Université (NU)-CHU Rouen, Normandie Université (NU)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Groupe de Recherche sur le Handicap Ventilatoire (GRHV), Normandie Université (NU)-Institute for Research and Innovation in Biomedicine (IRIB), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Universidad Diego Portales [Santiago] (UDP), Departamento de Astronomía y Astrofísica [Santiago], Pontificia Universidad Católica de Chile (UC), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Institute for Astronomy [Honolulu], University of Hawai‘i [Mānoa] (UHM), Deutsches Zentrum für Luft- und Raumfahrt (DLR), Astrophysikalisches Institut Potsdam (AIP), and Services communs OMP (UMS 831)

Subjects
Morphology, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Redshifts, Clusters: galaxy, Photometry: HST, ComputingMilieux_MISCELLANEOUS, Spectroscopy
Abstract

International audience

Published
2021

6. VizieR Online Data Catalog: Abell 370 MUSE redshifts (Lagattuta+, 2017)

Author

Lagattuta, D. J., Richard, J., Clement, B., Mahler, G., Patricio, V., Pello, R., Soucail, G., Schmidt, K. B., Wisotzki, L., Martinez, J., Bina, D., Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Service de réanimation médicale [CHU Rouen], Hôpital Charles Nicolle [Rouen], CHU Rouen, Normandie Université (NU)-Normandie Université (NU)-CHU Rouen, Normandie Université (NU)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Groupe de Recherche sur le Handicap Ventilatoire (GRHV), Normandie Université (NU)-Institute for Research and Innovation in Biomedicine (IRIB), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), and Deutsches Zentrum für Luft- und Raumfahrt (DLR)

Subjects
[PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Redshifts, Gravitational lensing, Clusters: galaxy, Photometry: HST, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2020

7. VizieR Online Data Catalog: MUSE and HFFs Photometry of A2744 (Mahler+, 2018)

Author

Mahler, G., Richard, J., Clement, B., Lagattuta, D., Schmidt, K., Patricio, V., Soucail, G., Bacon, R., Pello, R., Bouwens, R., Maseda, M., Martinez, J., Carollo, M., Inami, H., Leclercq, F., Wisotzki, L., Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Service de réanimation médicale [CHU Rouen], Hôpital Charles Nicolle [Rouen], CHU Rouen, Normandie Université (NU)-Normandie Université (NU)-CHU Rouen, Normandie Université (NU)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Groupe de Recherche sur le Handicap Ventilatoire (GRHV), Normandie Université (NU)-Institute for Research and Innovation in Biomedicine (IRIB), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), UCO/Lick Observatory, University of California [Santa Cruz] (UC Santa Cruz), University of California (UC)-University of California (UC), Institute for Astronomy [Zürich], Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Physiologie & médecine expérimentale du Cœur et des Muscles [U 1046] (PhyMedExp), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Hôpital Arnaud de Villeneuve [CHRU Montpellier], and Centre Hospitalier Régional Universitaire [Montpellier] (CHRU Montpellier)

Subjects
[PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Clusters: galaxy, Photometry: HST, ComputingMilieux_MISCELLANEOUS, Spectroscopy
Abstract

International audience

Published
2019

8. VizieR Online Data Catalog: LAE z\raisebox-0.5ex~3-7 luminosity functions (de La Vieuville+, 2019)

Author

La Vieuville, G., Bina, D., Pello, R., Mahler, G., Richard, J., Drake, A. B., Herenz, E. C., Bauer, F. E., Clement, B., Lagattuta, D., Laporte, N., Martinez, J., Patricio, V., Wisotzki, L., Zabl, J., Bouwens, R. J., Contini, T., Garel, T., Guiderdoni, B., Marino, R. A., Maseda, M. V., Matthee, J., Schaye, J., Soucail, G., Laboratoire d'Astrophysique de Marseille (LAM), and Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Gravitational lensing, Clusters: galaxy
Published
2019

10. The MUSE-Wide survey: detection of a clustering signal from Lyman α emitters in the range 3 < z < 6

Author

Diener , C., Wisotzki , L., Schmidt , K.B., Herenz , E.C., Urrutia , T., Garel , T., Kerutt , J., Saust , R.L., Bacon , R., Cantalupo , S., Contini , T., Guiderdoni , B., Marino , R.A., Richard , J., Schaye , J., Soucail , G., Weilbacher , P.M., Centre de Recherche Astrophysique de Lyon ( CRAL ), École normale supérieure - Lyon ( ENS Lyon ) -Université Claude Bernard Lyon 1 ( UCBL ), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ), École normale supérieure - Lyon ( ENS Lyon ), Institut de recherche en astrophysique et planétologie ( IRAP ), and Université Paul Sabatier - Toulouse 3 ( UPS ) -Observatoire Midi-Pyrénées ( OMP ) -Centre National de la Recherche Scientifique ( CNRS )

Subjects
galaxies: high-redshift, cosmology: observations, [ PHYS.ASTR ] Physics [physics]/Astrophysics [astro-ph]
Abstract

International audience; We present a clustering analysis of a sample of 238 Ly α emitters at redshift 3 ≲ z ≲ 6 from the MUSE-Wide survey. This survey mosaics extragalactic legacy fields with 1h MUSE pointings to detect statistically relevant samples of emission line galaxies. We analysed the first year observations from MUSE-Wide making use of the clustering signal in the line-of-sight direction. This method relies on comparing pair-counts at close redshifts for a fixed transverse distance and thus exploits the full potential of the redshift range covered by our sample. A clear clustering signal with a correlation length of $$r_{0}=2.9^{+1.0}_{-1.1}$$ Mpc (comoving) is detected. Whilst this result is based on only about a quarter of the full survey size, it already shows the immense potential of MUSE for efficiently observing and studying the clustering of Ly α emitters.

Published
2017
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11. Evidence for ram-pressure stripping in a cluster of galaxies at z = 0.7.

Author

Boselli, A., Epinat, B., Contini, T., Abril-Melgarejo, V., Boogaard, L. A., Pointecouteau, E., Ventou, E., Brinchmann, J., Carton, D., Finley, H., Michel-Dansac, L., Soucail, G., and Weilbacher, P. M.

Subjects
GALAXY clusters, SURFACE brightness (Astronomy), DISK galaxies, ACTIVE medium, GALAXIES, EVIDENCE, GALACTIC evolution
Abstract

Multi-Unit Spectroscopic Explorer (MUSE) observations of the cluster of galaxies CGr32 (M200 ≃ 2 × 1014 M⊙) at z = 0.73 reveal the presence of two massive star-forming galaxies with extended tails of diffuse gas detected in the [O II]λλ3727–3729 Å emission-line doublet. The tails, which have a cometary shape with a typical surface brightness of a few 10−18 erg s−1 cm−2 arcsec−2, extend up to ≃100 kpc (projected distance) from the galaxy discs, and are not associated with any stellar component. All this observational evidence suggests that the gas was removed during a ram-pressure stripping event. This observation is thus the first evidence that dynamical interactions with the intracluster medium were active when the Universe was only half its present age. The density of the gas derived using the observed [O II]λ3729/[O II]λ3726 line ratio implies a very short recombination time, suggesting that a source of ionisation is necessary to keep the gas ionised within the tail. [ABSTRACT FROM AUTHOR]

Published
2019
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12. New criteria for the selection of galaxy close pairs from cosmological simulations: evolution of the major and minor merger fraction in MUSE deep fields.

Author

Ventou, E., Contini, T., Bouché, N., Epinat, B., Brinchmann, J., Inami, H., Richard, J., Schroetter, I., Soucail, G., Steinmetz, M., and Weilbacher, P. M.

Subjects
GALAXY mergers, STELLAR mass, GALAXIES, FRACTIONS, STATISTICAL sampling, BIOLOGICAL evolution
Abstract

It remains a challenge to assess the merger fraction of galaxies at different cosmic epochs in order to probe the evolution of their mass assembly. Using the ILLUSTRIS cosmological simulation project, we investigate the relation between the separation of galaxies in a pair, both in velocity and projected spatial separation space, and the probability that these interacting galaxies will merge in the future. From this analysis, we propose a new set of criteria to select close pairs of galaxies along with a new corrective term to be applied to the computation of the galaxy merger fraction. We then probe the evolution of the major and minor merger fraction using the latest Multi-Unit Spectroscopic Explorer (MUSE) deep observations over the Hubble Ultra Deep Field, Hubble Deep Field South, COSMOS-Gr30, and Abell 2744 regions. From a parent sample of 2483 galaxies with spectroscopic redshifts, we identify 366 close pairs spread over a large range of redshifts (0.2 <  z <  6) and stellar masses (107 − 1011M⊙). Using the stellar mass ratio between the secondary and primary galaxy as a proxy to split the sample into major, minor, and very minor mergers, we found a total of 183 major, 142 minor, and 47 very minor close pairs corresponding to a mass ratio range of 1:1–1:6, 1:6–1:100, and lower than 1:100, respectively. Due to completeness issues, we do not consider the very minor pairs in the analysis. Overall, the major merger fraction increases up to z ≈ 2−3 reaching 25% for pairs where the most massive galaxy has a stellar mass M⋆ ≥ 109.5M⊙. Beyond this redshift, the fraction decreases down to ∼5% at z ≈ 6. The major merger fraction for lower-mass primary galaxies with M⋆ ≤ 109.5M⊙ seems to follow a more constant evolutionary trend with redshift. Thanks to the addition of new MUSE fields and new selection criteria, the increased statistics of the pair samples allow us to significantly shorten the error bars compared to our previous analysis. The evolution of the minor merger fraction is roughly constant with cosmic time, with a fraction of 20% at z <  3 and a slow decrease to 8−13% in the redshift range 3 ≤ z ≤ 6. [ABSTRACT FROM AUTHOR]

Published
2019
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13. X-ray observations and mass determinations in the cluster of galaxies Cl0024+17

Author

Soucail, G., Ota, N., Bohringer, H., Czoske, O., Hattori, M., Mellier, Y., Laboratoire Astrophysique de Toulouse-Tarbes (LATT), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Observatoire de Paris, and Université Paris sciences et lettres (PSL)

Subjects
X-RAYS: GALAXIES, COSMOLOGY: DARK MATTER, GALAXIES: CLUSTERS: GENERAL, [SDU]Sciences of the Universe [physics], Astrophysics::High Energy Astrophysical Phenomena, COSMOLOGY: OBSERVATIONS, Astrophysics (astro-ph), FOS: Physical sciences, GALAXIES: CLUSTERS: INDIVIDUAL: CL0024+17, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, COSMOLOGY: GRAVITATIONAL LENSING
Abstract

We present a detailed analysis of the mass distribution in the rich and distant cluster of galaxies Cl0024+17. X-ray data come from both a deep ROSAT/HRI image of the field (Bohringer et al. 1999) and ASCA spectral data. Using a wide field CCD image of the cluster, we optically identify all the faint X-ray sources, whose counts are compatible with deep X-ray number counts. In addition we marginally detect the X-ray counter-part of the gravitational shear perturbation detected by Bonnet et al. (1994) at a 2.5 $\sigma$ level. A careful spectral analysis of ASCA data is also presented. In particular, we extract a low resolution spectrum of the cluster free from the contamination by a nearby point source located 1.2 arcmin from the center. The X-ray temperature deduced from this analysis is $T_X = 5.7 ^{+4.9}_{-2.1}$ keV at the 90% confidence level. The comparison between the mass derived from a standard X-ray analysis and from other methods such as the Virial Theorem or the gravitational lensing effect lead to a mass discrepancy of a factor 1.5 to 3. We discuss all the possible sources of uncertainties in each method of mass determination and give some indications on the way to reduce them. A complementary study of optical data is in progress and may solve the X-ray/optical discrepancy through a better understanding of the dynamics of the cluster., Comment: Revised version, accepted in Astronomy and Astrophysics (Main Journal). Few changes in the discussion

Published
2000
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16. Kinematics, turbulence, and star formation of z ~ 1 strongly lensed galaxies seen with MUSE.

Author

Patrício, V., Richard, J., Carton, D., Contini, T., Epinat, B., Brinchmann, J., Schmidt, K. B., Krajnović, D., Bouché, N., Weilbacher, P. M., Pelló, R., Caruana, J., Maseda, M., Finley, H., Bauer, F. E., Martinez, J., Mahler, G., Lagattuta, D., Clément, B., and Soucail, G.

Subjects
STAR formation, KINEMATICS, TURBULENCE, GALAXIES, GINI coefficient, ASTRONOMICAL photometry, ATTENUATION (Physics)
Abstract

We analyse a sample of eight highly magnified galaxies at redshift 0.6 < z < 1.5 observed with MUSE, exploring the resolved properties of these galaxies at sub-kiloparsec scales. Combining multiband HST photometry and MUSE spectra, we derive the stellar mass, global star formation rates (SFRs), extinction and metallicity from multiple nebular lines, concluding that our sample is representative of z ~ 1 star-forming galaxies. We derive the 2D kinematics of these galaxies from the [OII ] emission and model it with a new method that accounts for lensing effects and fits multiple images simultaneously. We use these models to calculate the 2D beam-smearing correction and derive intrinsic velocity dispersion maps. We find them to be fairly homogeneous, with relatively constant velocity dispersions between 15 and 80 km s-1 and Gini coefficient of ≲0.3. We do not find any evidence for higher (or lower) velocity dispersions at the positions of bright star-forming clumps. We derive resolved maps of dust attenuation and attenuation-corrected SFRs from emission lines for two objects in the sample. We use this information to study the relation between resolved SFR and velocity dispersion. We find that these quantities are not correlated, and the high-velocity dispersions found for relatively low star-forming densities seems to indicate that, at sub-kiloparsec scales, turbulence in high-z discs is mainly dominated by gravitational instability rather than stellar feedback. [ABSTRACT FROM AUTHOR]

Published
2018
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17. Strong-lensing analysis of A2744 with MUSE and Hubble Frontier Fields images.

Author

Mahler, G., Richard, J., Clément, B., Lagattuta, D., Schmidt, K., Patrício, V., Soucail, G., Bacon, R., Pello, R., Bouwens, R., Maseda, M., Martinez, J., Carollo, M., Inami, H., Leclercq, F., and Wisotzki, L.

Subjects
GRAVITATIONAL lenses, SPECTRAL imaging, GALAXY clusters, REDSHIFT, DARK matter
Abstract

We present an analysis of Multi Unit Spectroscopic Explorer (MUSE) observations obtained on themassive Frontier Fields (FFs) cluster A2744. This newdata set covers the entiremultiply imaged region around the cluster core. The combined catalogue consists of 514 spectroscopic redshifts (with 414 new identifications). We use this redshift information to perform a stronglensing analysis revising multiple images previously found in the deep FF images, and add three new MUSE-detected multiply imaged systems with no obvious Hubble Space Telescope counterpart. The combined strong-lensing constraints include a total of 60 systems producing 188 images altogether, out of which 29 systems and 83 images are spectroscopically confirmed, making A2744 one of the most well-constrained clusters to date. Thanks to the large amount of spectroscopic redshifts, we model the influence of substructures at larger radii, using a parametrization including two cluster-scale components in the cluster core and several group scale in the outskirts. The resulting model accurately reproduces all the spectroscopic multiple systems, reaching an rms of 0.67 arcsec in the image plane. The large number of MUSE spectroscopic redshifts gives us a robust model, which we estimate reduces the systematic uncertainty on the 2D mass distribution by up to ~2.5 times the statistical uncertainty in the cluster core. In addition, from a combination of the parametrization and the set of constraints, we estimate the relative systematic uncertainty to be up to 9 per cent at 200 kpc. [ABSTRACT FROM AUTHOR]

Published
2018
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18. Ionised gas structure of 100 kpc in an over-dense region of the galaxy group COSMOS-Gr30 at z ~0.7.

Author

Epinat, B., Contini, T., Finley, H., Boogaard, L. A., Guérou, A., Brinchmann, J., Carton, D., Michel-Dansac, L., Bacon, R., Cantalupo, S., Carollo, M., Hamer, S., Kollatschny, W., Krajnović, D., Marino, R. A., Richard, J., Soucail, G., Weilbacher, P. M., and Wisotzki, L.

Subjects
GALACTIC evolution, IONIZED gases, STELLAR structure, ASTRONOMICAL observations, KINEMATICS, SUPERGIANT stars
Abstract

We report the discovery of a 104 kpc2 gaseous structure detected in [O ii]λλ3727, 3729 in an over-dense region of the COSMOS-Gr30 galaxy group at z ~ 0.725 with deep MUSE Guaranteed Time Observations. We estimate the total amount of diffuse ionised gas to be of the order of (~5 ± 3) × 1010 M⊙ and explore its physical properties to understand its origin and the source(s) of the ionisation. The MUSE data allow the identification of a dozen group members that are embedded in this structure through emission and absorption lines. We extracted spectra from small apertures defined for both the diffuse ionised gas and the galaxies. We investigated the kinematics and ionisation properties of the various galaxies and extended gas regions through line diagnostics (R23, O32, and [O iii]/Hβ) that are available within the MUSE wavelength range. We compared these diagnostics to photo-ionisation models and shock models. The structure is divided into two kinematically distinct sub-structures. The most extended sub-structure of ionised gas is likely rotating around a massive galaxy and displays filamentary patterns that link some galaxies. The second sub-structure links another massive galaxy that hosts an active galactic nucleus (AGN) to a low-mass galaxy, but it also extends orthogonally to the AGN host disc over ~ 35 kpc. This extent is likely ionised by the AGN itself. The location of small diffuse regions in the R23 vs. O32 diagram is compatible with photo-ionisation. However, the location of three of these regions in this diagram (low O32, high R23) can also be explained by shocks, which is supported by their high velocity dispersions. One edge-on galaxy shares the same properties and may be a source of shocks. Regardless of the hypothesis, the extended gas seems to be non-primordial. We favour a scenario where the gas has been extracted from galaxies by tidal forces and AGN triggered by interactions between at least the two sub-structures. [ABSTRACT FROM AUTHOR]

Published
2018
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19. Strong lensing as a probe of the mass distribution beyond the Einstein radius: Mass and light in SL2S J08544-0121, a galaxy group at z = 0.35

Author

Limousin, M., Jullo, E., Richard, J., Cabanac, R., Suyu, S. H., Halkola, A., Kneib, J.-P., Gavazzi, R., and Soucail, G.

Subjects
Astrophysics::Cosmology and Extragalactic Astrophysics
Abstract

Strong lensing has been employed extensively to obtain accurate mass measurements within the Einstein radius. We here use strong lensing to probe mass distributions beyond the Einstein radius. We consider SL2S J08544-0121, a galaxy group at redshift z=0.35 with a bimodal light distribution and with a strong lensing system located at one of the two luminosity peaks separated by ~54". The main arc and the counter-image of the strong lensing system are located at ~5" and ~8" from the lens galaxy centre. We find that a simple elliptical isothermal potential cannot satisfactorily reproduce the strong lensing observations. However, with a mass model for the group built from its light-distribution with a smoothing factor s and a mass-to-light ratio M/L, we obtain an accurate reproduction of the observations. We find M/L = 98 ± 27 (i band, solar units, not corrected for evolution) and s = 20" ± 9 (2σ confidence level). Moreover, we use weak lensing to independently estimate the mass of the group, and find a consistent M/L in the range 66-146 (1-σ confidence level). This suggests that light is a good tracer of mass. Interestingly, this also shows that a strong lensing-only analysis (on scales of ~10") can constrain the properties of nearby objects (on scales of ~100"). We characterise the type of perturbed strong lensing system that allows such an analysis: a non dominant strong lensing system used as a test particle to probe the main potential. This kind of analysis needs to be validated with other systems because it could provide a quick way of probing the mass distribution of clusters and groups. This is particularly relevant in the context of forthcoming wide-field surveys, which will yield thousands of strong lenses, some of which perturbed enough to pursue the analysis proposed in this paper.

Published
2010

20. Solving the Abell 1689 puzzle: A combined strong and weak gravitational lensing analysis

Author

Limousin, M., Richard, J., Kneib, J. -P., Jullo, E., Fort, B., Soucail, G., Elíasdóttir, A., Natarajan, P., Smail, I., Ellis, R. S., Czoske, O., Hudelot, P., Bardeau, Sebastien, Ebeling, H., Smith, G. P., Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire aquitain des sciences de l'univers (OASU), Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), and Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], cosmology: observations — galaxies: clusters: individual (A1689) — gravita- tional lensing, Astrophysics::Cosmology and Extragalactic Astrophysics
Abstract

40 pages, 17 figures, high resolution draft at http://www.dark-cosmology.dk/~marceau/1689.pdf; astro-ph/0612165; We present a reconstruction of the mass distribution of galaxy cluster Abell 1689 at z = 0.18 using detected strong lensing features from deep HST/ACS observations and extensive ground based spectroscopy. Earlier analyses have reported up to 32 multiply imaged systems in this cluster, of which only 3 were spectroscopically confirmed. In this work, we present a parametric strong lensing mass reconstruction using 24 multiply imaged systems with newly determined spectroscopic redshifts, which is a major step forward in building a robust mass model. In turn, the new spectroscopic data allows a more secure identification of multiply imaged systems. The resultant mass model enables us to reliably predict the redshifts of additional multiply imaged systems for which no spectra are currently available, and to use the location of these systems to further constrain the mass model. In particular, we have detected 5 strong galaxy-galaxy lensing systems just outside the Einstein ring region, further constraining the mass profile. Our strong lensing mass model is consistent with that inferred from our large scale weak lensing analysis derived using CFH12k wide field images. Thanks to a new method for reliably selecting a well defined background lensed galaxy population, we resolve the discrepancy found between the strong and weak lensing mass models reported in earlier work. [ABRIDGED]

Published
2007

21. Morphological evolution of z~1 galaxies from deep K-band AO imaging in the COSMOS deep field

Author

Huertas-Company, M., Rouan, D., Soucail, G., F��vre, O. Le, Tasca, L., Contini, T., Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), and Beaussier, Catherine

Subjects
[PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], [PHYS.ASTR.CO] Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Astrophysics (astro-ph), FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

We present the results of an imaging programme of distant galaxies (z~0.8) at high spatial resolution (~0.1").We observed 7 fields of 1'*1' with the NACO Adaptive Optics system (VLT) in Ks (2.16um) band with typical V ~ 14 guide stars and 3h integration time per field. Observed fields are selected within the COSMOS survey area. High angular resolution K-band data have the advantage to probe old stellar populations in the rest-frame, enabling to determine galaxy morphological types unaffected by recent star formation, better linked to the underlying mass than classical optical morphology studies (HST). Adaptive optics on ground based telescopes is the only method today to obtain such high resolution in the K-band. In this paper we show that reliable results can be obtained and establish a first basis for larger observing programmes. We analyze the morphologies by means of B/D (Bulge/Disk) decomposition with GIM2D and CAS (Concentration-Asymmetry) estimators for 79 galaxies with magnitudes between Ks = 17-23 and classify them in three main morphological types (Late Type, Early Type and Irregulars). We obtain for the first time an estimate of the distribution of galaxy types at redshift z ~ 1 as measured from the near infrared at high spatial resolution. We show that galactic parameters (disk scale length, bulge effective radius and bulge fraction) can be estimated with a random error lower than 20% for the bulge fraction up to Ks = 19 (AB = 21) and that classification into the three main morphological types can be done up to Ks = 20 (AB = 22) with at least 70% of correct identifications. We used the known photometric redshifts to obtain a redshift distribution over 2 redshift bins (z < 0.8, 0.8 < z < 1.5) for each morphological type., 19 pages, 19 figures, 5 tables, Accepted for publication in A&A, typos corrected, referee's suggestions added, figure 3 has been strongly degraded

Published
2006

22. Depletion curves of galaxy number counts behind cluster lenses

Author

Mayen, C. and Soucail, G.

Subjects
Astrophysics (astro-ph), FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics
Abstract

When the logarithmic slope of the galaxy counts is lower than 0.4 (this is the case in all filters at high magnitude), the magnification bias due to the lens makes the number density of objects decrease. Consequently, the radial distribution shows a typical depletion curve. We present simulations of depletion curves obtained for a variety of different lens models and we show how the model parameters affect the depletion area., 2 pages, includes 1 postscript figure, uses PASP conference proceedings substyle definition for LaTeX. Poster contribution to "Gravitational Lensing : Recent Progress and Future Goals", Boston University, July 1999, ed. T. G. Brainerd and C. S. Kochanek

Published
1999

23. Emission-Line Properties of MG2016+112: A Luminous Type-2 Quasar at High Redshift

Author

Yamada, T., Yamazaki, S., Hattori, M., Soucail, G., and Kneib, J. -P.

Subjects
Astrophysics::High Energy Astrophysical Phenomena, Astrophysics (astro-ph), FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

We present new high signal-to-noise ratio spectra of the components B and C of the gravitational lensing system MG2016+112. We show that image C displays strong emission lines of Ly$\alpha$, \NV, \CIV, \HeII, and \CIII redshifted to z=3.27, similar to images and B. We examine the emission-line flux ratios in order to put constraints on the lens models as well as to investigate the intrinsic nature of MG2016+112. The observed line ratios of B and C are consistent with those expected in the simple photo-ionization models for narrow-line region of active galactic nuclei (AGN) except for the enhanced \NV\ lines. The line ratios difference of components B and C can be interpreted as a difference in ionization parameters. This result is consistent with lens model prediction that C is a fold image of a slightly outer part of the nucleus. MG2016+112 is known to be very unique among the high-redshift AGN; it is neither an ordinary broad-line quasar nor a powerful radio galaxy as indicated by the width and flux ratio of the emission lines. Together with other observed properties discussed in literature, we argue that MG2016+112 is the highest redshift luminous radio-quiet type-2 quasar., Comment: 8 pages, submitted to Astronomy and Astrophysics

Published
1999

24. A ring galaxy at z=1 lensed by the cluster Abell 370

Author

Soucail, G., Kneib, J. P., Bézecourt, J., Metcalfe, L., Bruno Altieri, Le Borgne, J. F., Kapteyn Astronomical Institute, and Astronomy

Subjects
galaxies : evolution, Astrophysics (astro-ph), FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, galaxies : interactions, Astrophysics, cosmology : observations, SPACE-TELESCOPE OBSERVATIONS, galaxies : Seyfert, galaxies : individual : LRG J0239-0134, cosmology : gravitational lensing, ARCS, Astrophysics::Earth and Planetary Astrophysics, FIELD, Astrophysics::Galaxy Astrophysics
Abstract

We present a study of a very peculiar object found in the field of the cluster-lens Abell 370. This object displays, in HST imaging, a spectacular morphology comparable to nearby ring-galaxies. From spectroscopic observations at the CFHT, we measured a redshift of $z=1.062$ based on the identification of [O ii] 3727 \AA and [Ne v] 3426 \AA emission lines. These emission lines are typical of starburst galaxies hosting a central active nucleus and are in good agreement with the assumption that this object is a ring-galaxy. This object is also detected with ISO in the LW2 and LW3 filters, and the mid Infra-Red (MIR) flux ratio favors a Seyfert 1 type. The shape of the ring is gravitationally distorted by the cluster-lens, and most particularly by a nearby cluster elliptical galaxy. Using the cluster mass model, we can compute its intrinsic shape. Requiring that the outer ring follows an ellipse we put constraints on the M/L ratio of the nearby galaxy and derive a magnification factor of 2.5 $\pm$ 0.2. The absolute luminosities of the source are then $L_B = 1.3 \ 10^{12} L_{B \odot}$ and $\nu$ L$_\nu \simeq 4. 10^{10}$ L$_\odot$ in the mid-IR., Comment: 5 pages, 5 figures, uses aa.cls, accepted to A&A Letters. Minor changes, Figure 1 revisited and typos added

Published
1999

25. AgapeZ1: a Large Amplification Microlensing Event or an Odd Variable Star Towards the Inner Bulge of M31

Author

Ansari, R., Aurière, M., Baillon, P., Bouquet, A., Coupinot, G., Coutures, Ch, Ghesquière, C., Giraud-Héraud, Y., Paolo Gondolo, Hecquet, J., Kaplan, J., Kim, A., Le Du, Y., Melchior, A. L., Moniez, M., Picat, J. P., Soucail, G., Laboratoire de l'Accélérateur Linéaire (LAL), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Physique Corpusculaire et Cosmologie - Collège de France (PCC), Collège de France (CdF (institution))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and AGAPE

Subjects
[PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Astrophysics and Astronomy, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Astrophysics (astro-ph), FOS: Physical sciences, document supplier/ library /use/ bibliometric distributions, Astrophysics, informetric
Abstract

AgapeZ1 is the brightest and the shortest duration microlensing candidate event found in the Agape data. It occured only 42" from the center of M31. Our photometry shows that the half intensity duration of the event6 is 4.8 days and at maximum brightness we measure a stellar magnitude of R=18.0 with B-R=0.80 mag color. A search on HST archives produced a single resolved star within the projected event position error box. Its magnitude is R=22., Comment: 4 pages with 5 figures

Published
1999

26. Lensed galaxies in Abell 370 I. Modeling the number counts and redshift distribution of background sources

Author

Bézecourt, J., Jean-Paul Kneib, Soucail, G., Ebbels, T. M. D., and Kapteyn Astronomical Institute

Subjects
galaxies : evolution, galaxies : clusters : individual : A 370, RICH CLUSTER AC-114, Astrophysics (astro-ph), FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, GIANT ARCS, EVOLUTION, ARC STATISTICS, GRAVITATIONAL ARCLETS, cosmology : observations, SPACE-TELESCOPE OBSERVATIONS, cosmology : gravitational lensing, RECONSTRUCTION, FIELD, DISTANT CLUSTER, Astrophysics::Galaxy Astrophysics, MASS-DISTRIBUTION
Abstract

We present new observations of the cluster-lens Abell 370: a deep HST/WFPC2 F675W image and ESO 3.6m spectroscopy of faint galaxies. These observations shade new lights on the statistical properties of faint lensed galaxies. In particular, we spectroscopically confirm the multiple image nature of the B2--B3 gravitational pair (Kneib et al. 1993), and determine a redshift of z=0.806 which is in very good agreement with earlier predictions. A refined mass model of the cluster core (that includes cluster galaxy halos) is presented, based on a number of newly identified multiple images. Following Bezecourt et al. (1998a), we combine the new cluster mass model with a spectrophotometric prescription for galaxy evolution to predict the arclets number counts and redshift distribution in the HST image. In particular, the ellipticity distribution of background sources is taken into account, in order to properly estimate the statistical number and redshift distribution of arclets. We show that the redshift distribution of arclets, and particularly its high redshift tail can be used as a strong constraint to disentangle different galaxy evolution scenario. A hierarchical model which includes a number density evolution is favored by our analysis. Finally, we compute the depletion curves in the faint galaxies number counts and discuss its wavelength dependence., 10 pages, Astronomy and Astrophysics in press

Published
1998

27. MUSE observations of the lensing cluster Abell 1689.

Author

Bina, D., Pelló, R., Richard, J., Lewis, J., Patrício, V., Cantalupo, S., Herenz, E. C., Soto, K., Weilbacher, P. M., Bacon, R., Vernet, J. D. R., Wisotzki, L., Clément, B., Cuby, J. G., Lagattuta, D. J., Soucail, G., and Verhamme, A.

Subjects
SPECTROGRAPHS, ASTRONOMICAL instruments, GRAVITATIONAL lenses, GRAVITATIONAL effects, ASTROPHYSICS, REDSHIFT
Abstract

Context. This paper presents the results obtained with the Multi Unit Spectroscopic Explorer (MUSE) for the core of the lensing cluster Abell 1689, as part of MUSE's commissioning at the ESO Very Large Telescope. Aims. Integral-field observations with MUSE provide a unique view of the central 1 × 1 arcmin2 region at intermediate spectral resolution in the visible domain, allowing us to conduct a complete census of both cluster galaxies and lensed background sources. Methods. We performed a spectroscopic analysis of all sources found in the MUSE data cube. Two hundred and eighty-two objects were systematically extracted from the cube based on a guided-and-manual approach. We also tested three different tools for the automated detection and extraction of line emitters. Cluster galaxies and lensed sources were identified based on their spectral features. We investigated the multiple-image configuration for all known sources in the field. Results. Previous to our survey, 28 di erent lensed galaxies displaying 46 multiple images were known in the MUSE field of view, most of them were detected through photometric redshifts and lensing considerations. Of these, we spectroscopically confirm 12 images based on their emission lines, corresponding to 7 different lensed galaxies between z = 0.95 and 5.0. In addition, 14 new galaxies have been spectroscopically identified in this area thanks to MUSE data, with redshifts ranging between 0.8 and 6.2. All background sources detected within the MUSE field of view correspond to multiple-imaged systems lensed by A1689. Seventeen sources in total are found at z ≥ 3 based on their Lyman-α emission, with Lyman-α luminosities ranging between 40:5 ≲ log(Lyα) ≲ 42:5 after correction for magnification. This sample is particularly sensitive to the slope of the luminosity function toward the faintest end. The density of sources obtained in this survey is consistent with a steep value of α ≤-1.5, although this result still needs further investigation. Conclusions. These results illustrate the effciency of MUSE in characterizing lensing clusters on one hand and in studying faint and distant populations of galaxies on the other hand. In particular, our current survey of lensing clusters is expected to provide a unique census of sources responsible for the reionization in a representative volume at z ~ 4-7. [ABSTRACT FROM AUTHOR]

Published
2016
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28. Pixel Lensing

Author

Ansari, R., Auriere, M., Baillon, P., Bouquet, A., Coupinot, G., Coutures, Ch., Ghesquiere, C., Giraud-Heraud, Y., Gondolo, P., Hecquet, J., Kaplan, J., Kim, A., Le Du, Y., Melchior, A-L., Moniez, M., Picat, J-P., Soucail, G., Physique Corpusculaire et Cosmologie - Collège de France (PCC), Collège de France (CdF (institution))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Lantz, Simone

Subjects
[PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], [PHYS.ASTR.CO] Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO]
Published
1997

29. AGAPE:Andromeda Gravitational Amplification Pixel Experiment

Author

Ansari, R., Auriere, M., Baillon, P., Bouquet, A., Coupinot, G., Coutures, Ch., Ghesquiere, C., Giraud-Heraud, Y., Gondolo, P., Hecquet, J., Kaplan, J., Kim, A., Le Du, Y., Melchior, A-L., Moniez, M., Picat, J-P., Soucail, G., Physique Corpusculaire et Cosmologie - Collège de France (PCC), Collège de France (CdF (institution))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Lantz, Simone

Subjects
[PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], [PHYS.ASTR.CO] Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Digital Document, Theory, Document, Electronic document
Abstract

This paper presents a collective analytic work on the document in its transition to digital form carried out within a network of researchers of the CNRS Information and Communication Science and Technology (STIC) Department. The collective drafting of a text, carried out with a device of annotations, built an analytical inventory of research in progress. It stressed three topics: the form, the text and the medium which reflect the radical transformations that are taking place and the issues still going on. In particular, the more and more dynamic construction of documents actually transforms their traditional stability. The advance of the collective thought could lead to the development of a theory of the document.

Published
1997

30. AGAPE : Andromeda Gravitational Amplification Pixel Experiment

Author

Baillon, P., Ansari, R., Auriere, M., Bouquet, A., Coupinot, G., Coutures, Ch., Ghesquiere, C., Giraud-Heraud, Y., Gondolo, P., Hecquet, J., Kaplan, J., Kim, A., Le Du, Y., Melchior, A-L., Moniez, M., Picat, J-P., Soucail, G., Lantz, Simone, Physique Corpusculaire et Cosmologie - Collège de France (PCC), and Collège de France (CdF (institution))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], [PHYS.ASTR.CO] Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO]
Published
1997

31. Redshift survey of gravitational arclets in Abell 2390

Author

Bezecourt, J. and Soucail, G.

Subjects
Astrophysics (astro-ph), FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

In this paper, we present new determinations of redshifts on a sample of gravitational arclets identified in the cluster of galaxies Abell 2390. The arclets candidates were selected from their elongated morphology as seen in recent deep HST images of the cluster. The spectra display various features, and the redshifts of the background objects range from 0.398 to 1.268, most of them being between 0.6 and 0.9 with [O II] $\lambda$=3727\AA\ being the main emission line encountered. This distribution is mostly concentrated in two redshifts planes at $z=0.64$ and $z=0.90$. The existence of two pairs of background galaxies at different redshifts, almost superimposed on the same line of sight are used to infer some limits on the mass of galaxy-size deflectors. A detailed writing of the lensing distorsion by two lens planes at different redshifts is developped for this purpose. Finally, [O II] equivalent widths are used to compute approximate star formation rates which appear to be of the same order of magnitude as in nearby spiral galaxies. The implications on both the lensing properties of the cluster and the analysis of the field galaxy evolution are also discussed., Comment: 10 pages, Latex with 10 postscript figures, accepted by Astronomy and Astrophysics, postscript file also available by anonymous ftp at ftp://summer.obs-mip.fr/pub/OUTGOING/a2390.ps.Z or upon request at bezecour@obs-mip.fr

Published
1996

32. Identification of a high redshift cluster in the field of Q2345+007 through deep BRIJK' photometry

Author

Pello, R., Miralles, Jm, Leborgne, Jf, Picat, Jp, Soucail, G., and Bruzual, G.

Subjects
Astrophysics (astro-ph), FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

This paper describes new results on the identification of the complex gravita- tional lens responsible for the double quasar Q2345+007. A gravitational shear field was detected recently about 45'' away from the QSO, centered on an excess of faint blue galaxies. We present deep photometric data in the near-IR (J & K'), which are used together with optical BRI photometry to build spectral ener- gy distributions for all the objects, and to derive a photometric redshift esti- mate by comparison with synthetic spectrophotometric data. We propose a statis- tical method to analyse the distribution in z. An excess of galaxies at z about 0.75 is detected in this field, with a 2D distribution showing a maximum located at the center of the weak-shear field. The z inferred for this overdensity (a distant cluster of galaxies) corresponds to an absorption system in the spectrum of the quasar B. Most cluster-member candidates at z=0.75 are undergoing a star- formation process or are burst systems 1 to 3 Gyr old. We also discuss the exis- tence of other possible excesses of galaxies at different z planes., 16 pages, A & A macros (l-aa.sty), 11 postcript fig. included with psfig, to appear in Astronomy & Astrophysics Main Journal

Published
1996

33. AGAPE: a microlensing search in the direction of M31

Author

Ansari, R., Auriere, M., Baillon, P., Bouquet, A., Coupinot, G., Coutures, C., Ghesquiere, C., Giraud-Heraud, Y., Gondolo, P., Hecquet, J., Kaplan, J., Le Du, Y., Melchior, A.L., Moniez, M., Picat, J.P., and Soucail, G.

Subjects
Astrophysics and Astronomy
Abstract

A status report of the microlensing search by the pixel method in the direction of M31, on the 2 meter telescope at Pic du Midi is given. Pixels are stable to a level better than 0.5%. Pixel variations as small as 0.02 magnitude can clearly be detected.

Published
1996

34. AGAPE : a microlensing search in the direction of M31 : status report

Author

Ansari, R., Auriere, M., Baillon, P., Bouquet, A., Coupinot, G., Coutures, C., Ghesquiere, C., Giraud-Heraud, Y., Gondolo, P., Hecquet, J., Kaplan, J., Du, Y. Le, Melchior, A. L., Moniez, M., Picat, J. P., Soucail, G., Laboratoire de l'Accélérateur Linéaire (LAL), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Physique Corpusculaire et Cosmologie - Collège de France (PCC), Collège de France (CdF (institution))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Bernabei R., and Lantz, Simone

Subjects
[PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], [PHYS.ASTR.CO] Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Astrophysics (astro-ph), FOS: Physical sciences, Astrophysics, [SDU.ASTR] Sciences of the Universe [physics]/Astrophysics [astro-ph]
Abstract

A status report of the microlensing search by the pixel method in the direction of M31, on the 2 meter telescope at Pic du Midi is given. Pixels are stable to a level better than 0.5%. Pixel variations as small as 0.02 magnitude can clearly be detected., 5 pages, Latex2e, includes 5 figures, uuencoded gziped tar file. Proceedings of the workshop ``The dark side of the Universe : experimental efforts and theoretical framework'' Roma 13-14 November 1995

Published
1995

35. The Core of Cluster-Lenses

Author

Kneib, J. -P. and Soucail, G.

Subjects
Astrophysics (astro-ph), FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

The gravitational lensing of faint background galaxies by rich clusters is emerging as a very efficient method to constrain both the mass distribution of cluster of galaxies and probe the statistical properties of faint background galaxies. We review here the results concerning the core of cluster lenses, where recent Hubble Space Telescope (HST) images are giving a new insight in the gravitational distortion phenomena., uuencoded compressed postscript. The preprint is also available at http://www.ast.cam.ac.uk/preprint/PrePrint.html

Published
1995

36. AGAPE : Detection de naines brunes dans les halos de galaxies par effet de microlentille gravitationnelle sur les etoiles M31

Author

Giraud-Heraud, Y., Ansari, R., Auriere, M., Baillon, P., Bouquet, A., Coupinot, G., Coutures, C., Ghesquiere, C., Gondolo, P., Hecquet, J., Kaplan, J., Melchior, A-L., Moniez, M., Picat, J-P., Soucail, G., Physique Corpusculaire et Cosmologie - Collège de France (PCC), Collège de France (CdF (institution))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Lantz, Simone

Subjects
[PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], [PHYS.ASTR.CO] Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO]
Published
1995

37. The matter distribution in z ~ 0.5 redshift clusters of galaxies.

Author

Soucail, G., Foëx, G., Pointecouteau, E., Arnaud, M., and Limousin, M.

Subjects
*GALACTIC redshift, *GALAXY clusters, *DARK matter, *GAS distribution, *GRAVITATIONAL lenses
Abstract

We present an optical analysis of a sample of 11 clusters built from the EXCPRES sample of X-ray selected clusters at intermediate redshift (z ~ 0:5).With a careful selection of the background galaxies, we provide the mass maps reconstructed from the weak lensing by the clusters. We compare them with the light distribution traced by the early-type galaxies selected along the red sequence for each cluster. The strong correlations between dark matter and galaxy distributions are confirmed, although some discrepancies arise, mostly for merging or perturbed clusters. The average M=L ratio of the clusters is found to be M=Lr = 160 ~ 60 in solar units (with no evolutionary correction), in excellent agreement with similar previous studies. No strong evolutionary e~ects are identified, although the small sample size reduces the significance of the result. We also provide a individual analysis of each cluster in the sample with a comparison between the dark matter, the galaxies, and the gas distributions. Some of the clusters are studied in the optical for the first time. [ABSTRACT FROM AUTHOR]

Published
2015
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38. First Results from the VIMOS-IFU Survey of Gravitationally Lensing Clusters at z ∼ 0.2.

Author

Leibundgut, Bruno, Kissler-Patig, Markus, Walsh, Jeremy R., Roth, Martin M., Covone, G., Kneib, J.-P., Soucail, G., Jullo, E., and Richard, J.

Abstract

We present the on-going observational program of a VIMOS Integral Field Unit survey of the central regions of massive, gravitational lensing galaxy clusters at redshift z ≃ 0.2. We have observed six clusters using the low-resolution blue grism (R ≃ 200), and the spectroscopic survey is complemented by a wealth of photometric data, including Hubble Space Telescope optical data and near infrared VLT data. The principal scientific aims of this project are: the study of the high-z lensed galaxies, the transformation and evolution of galaxies in cluster cores and the use of multiple images to constrain cosmography. We briefly report here on the first results from this project on the clusters Abell 2667 and Abell 68. [ABSTRACT FROM AUTHOR]

Published
2007
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39. A VIMOS-IFU Survey of z ∼ 0.2 Massive Lensing Galaxy Clusters: Constraining Cosmography.

Author

Leibundgut, Bruno, Kissler-Patig, Markus, Walsh, Jeremy R., Roth, Martin M., Soucail, G., Covone, G., and Kneib, J.-P.

Abstract

We present an integral field spectroscopy survey of rich clusters of galaxies aimed at studying their lensing properties. Thanks to knowledge of the spectroscopic characteristics of more than three families of multiple images in a single lens, one is able in principle to derive constraints on the geometric cosmological parameters. We show that this ambitious program is feasible and present some new results, in particular the redshift measurement of the giant arc in A2667 and the redshift confirmation of the counter-image of the radial arc in MS2137-23. Prospects for the future of such a program are presented. [ABSTRACT FROM AUTHOR]

Published
2007
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40. Characterizing SL2S galaxy groups using the Einstein radius.

Author

Magris, G., Mejía-Narváez, A. J., Fernández-Trincado, J. G., Verdugo, T., Blakeslee, J. P., Motta, V., Foëx, G., Forero-Romero, J. E., Muñoz, R. P., Pello, R., Cabanac, R., Limousin, M., More, A., and Soucail, G.

Subjects
GRAVITATIONAL lenses, GALAXIES, LUMINOSITY, COMPUTER simulation
Abstract

Aims. We aim to study the reliability of RA (the distance from the arcs to the center of the lens) as a measure of the Einstein radius in galaxy groups. In addition, we want to analyze the possibility of using RA as a proxy to characterize some properties of galaxy groups, such as luminosity (L) and richness (N). Methods. We analyzed the Einstein radius, θE, in our sample of Strong Lensing Legacy Survey (SL2S) galaxy groups, and compared it with RA, using three different approaches: 1) the velocity dispersion obtained from weak lensing assuming a singular isothermal sphere profile (θE,I); 2) a strong lensing analytical method (θE,II) combined with a velocity dispersion-concentration relation derived from numerical simulations designed to mimic our group sample; and 3) strong lensing modeling (θE,III) of eleven groups (with four new models presented in this work) using Hubble Space Telescope (HST) and Canada-France-Hawaii Telescope (CFHT) images. Finally, RA was analyzed as a function of redshift z to investigate possible correlations with L, N, and the richness-to-luminosity ratio (N/L). Results. We found a correlation between θE and RA, but with large scatter. We estimate θE,I = (2.2 ± 0.9) + (0.7 ± 0.2)RA, θE,II = (0.4 ± 1.5) + (1.1 ± 0.4)RA, and θE,III = (0.4 ± 1.5) + (0.9 ± 0.3)RA for each method respectively. We found weak evidence of anticorrelation between RA and z, with Log RA = (0.58 ± 0.06) - (0.04 ± 0.1)z, suggesting a possible evolution of the Einstein radius with z, as reported previously by other authors. Our results also show that RA is correlated with L and N (more luminous and richer groups have greater RA), and a possible correlation between RA and the N/L ratio. Conclusions. Our analysis indicates that RA is correlated with θE in our sample, making RA useful for characterizing properties like L and N (and possibly N/L) in galaxy groups. Additionally, we present evidence suggesting that the Einstein radius evolves with z. [ABSTRACT FROM AUTHOR]

Published
2014
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41. Deep optical observations of the massive galaxy cluster Abell 1413.

Author

Castagné, D., Soucail, G., Pointecouteau, E., Cappi, A., Maurogordato, S., Benoist, C., and Ferrari, C.

Subjects
*GALAXY clusters, *MORPHOLOGY, *DYNAMICS, *SPECTROSCOPIC imaging, *DENSITY, *DISPERSION (Chemistry)
Abstract

Aims. We investigate the morphology and dynamics of the massive nearby galaxy cluster Abell 1413. Methods. Using wide field imaging and spectroscopic data obtained from observations at the Canada-France-Hawaii Telescope and archival SDSS data, we build a sample of more than 250 galaxies covering a region centered on the cluster and extending to its outskirts on large scales. Results. We probe the cluster morphology analyzing the projected density distribution of galaxies and find a strong variation in the ellipticity of the distribution, from 0.8 at the center of the cluster down to ~0.35 at the periphery. This may be the tracer of a prolate global mass distribution, slightly attenuated in the collisional distribution of the gas. We also study the large scale environment, identifying several structures associated to the cluster and organized along the major axis in the North-South direction. From spectroscopic data we derive the velocity dispersion and we investigate the overall dynamics of the cluster. The regular velocity dispersion supports the case for a prolate cluster aligned in the plane of the sky and embedded in a larger scale structure. [ABSTRACT FROM AUTHOR]

Published
2012
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42. The dark matter distribution in z ∼0.5 clusters of galaxies I. Determining scaling relations with weak lensing masses.

Author

Foëx, G., Soucail, G., Pointecouteau, E., Arnaud, M., Limousin, M., and Pratt, G.W.

Subjects
*GALAXY clusters, *GRAVITATIONAL lenses, *HALOS (Meteorology), *HYDROSTATIC pressure, *COSMOLOGICAL distances
Abstract

The total mass of clusters of galaxies is a key parameter for studing massive halos. It relates to numerous gravitational and baryonic processes at play in the framework of large-scale structure formation, thus rendering its determination both important and challenging. From a sample of the 11 X-ray bright clusters selected from the EXCPRES sample, we investigate the optical and X-ray properties of clusters with respect to their total mass derived from weak gravitational lensing. From multicolor, wide-field imaging obtained with MegaCam at CFHT, we derive the shear profile of each individual cluster of galaxies. We carefully investigate all systematic sources related to the weak lensing mass determination. The weak lensing masses are then compared to the X-ray masses obtained from the analysis of XMM-Newton observations assuming hydrostatic equilibrium. We find good agreement between the two mass proxies although a few outliers with either perturbed morphology or poor quality data prevent deriving robust mass estimates. The weak lensing mass is also correlated with the optical richness and the total optical luminosity, as well as with the X-ray luminosity, to provide scaling relations within the redshift range 0.4 < z < 0.6. These relations are in good agreement with previous works at lower redshifts. For the LX - M relation we combine our sample with two other cluster and group samples from the literature, thus covering two decades in mass and X-ray luminosity, with a regular and coherent correlation between the two physical quantities. [ABSTRACT FROM AUTHOR]

Published
2012
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43. AGAPE, a microlensing search in the direction of M31: status report.

Author

Ansari, R., Aurière, M., Baillon, P., Bouquet, A., Coupinot, G., Coutures, C., Ghesquière, C., Giraud-Héraud, Y., Gondolo, P., Hecquet, J., Kaplan, J., Le Du, Y., Melchior, A. L., Moniez, M., Picat, J. P., and Soucail, G.

Subjects
MICROLENSING (Astrophysics), ANDROMEDA Galaxy, LARGE magellanic cloud, GALACTIC halos, COMPACT objects (Astronomy)
Published
1996

45. The galaxy population of the z = 1 cluster of galaxies MG2016+112.

Author

Toft, S., Soucail, G., and Hjorth, J.

Subjects
*GALAXY clusters, *REDSHIFT, *ASTRONOMY
Abstract

Reports on the galaxy population of the z=1 cluster of galaxies MG2016+112. Photometric redshift analysis of galaxies; Population of 69 galaxies with photometric red shifts consistent with being in a cluster at the redshift of the giant elliptical lensing galaxy z=1.00; Representation of the Ks-band luminosity function of the cluster galaxies by the Schechter function.

Published
2003
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46. Exploring Massive Galaxy Clusters: XMM-Newton observations of two morphology unbiased samples at z ∼ 0.2 and z ∼ 0.3.

Author

Leibundgut, Bruno, Pratt, G.W., Zhang, Y.-Y., Finoguenov, A., Böhringer, H., Kneib, J.-P., Smith, G. P., Czoske, O., Soucail, G., Schuecker, P., Ikebe, Y., Matsushita, K., Guzzo, L., and Collins, C. A.

Abstract

For the spectral determination of the temperature distribution in galaxy clusters we developed a double background subtraction method, and applied it to 2 morphology unbiased samples of X-ray luminous galaxy clusters (12 at z ∼0.2, 13 at z ∼0.3) observed by XMM-Newton. The scaled profiles of the X-ray properties show a self-similar behaviour above 0.2r500 for both samples. The tight X-ray scaling relations of the 2 samples show no evolution compared to the nearby and more distant samples. The X-ray lensing masses converge for most clusters. [ABSTRACT FROM AUTHOR]

Published
2007
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49. The remarkable lens cluster A2390.

Author

Pierre, M., Le Borgne, J.F., Soucail, G., and Kneib, J. P.

Subjects
GALAXY clusters, ASTROPHYSICS
Abstract

Presents the most important results obtained from a detailed combined X-ray/optical analysis of the lens cluster A2390. X-ray observations and morphological analysis; Analysis of the X-ray flux and profile; Lensing constraints on the gravitational potential; Conclusion.

Published
1998

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