The EROS2 search for microlensing events towards the spiral arms: the complete seven season results
| العنوان: | The EROS2 search for microlensing events towards the spiral arms: the complete seven season results |
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| المؤلفون: | Christophe Magneville, P. Bareyre, J. de Kat, Roger Ferlet, Y. R. Rahal, E. Maurice, N. Palanque-Delabrouille, C. Hamadache, L. Le Guillou, F. Derue, Cristina Afonso, B. Mansoux, P. Fouque, M. Gros, Anaëlle Maury, F. Couchot, X. Charlot, C. Loup, Alfred Vidal-Madjar, J. F. Glicenstein, Sohrab Rahvar, E. Lesquoy, Jean-Philippe Beaulieu, Bertrand Goldman, P. Tisserand, J. Haissinski, C. Coutures, A. Milsztajn, D. Graff, J. N. Albert, O. Perdereau, Éric Aubourg, J. B. Marquette, R. Ansari, Jeffrey A. Rich, M. Moniez, Johannes Andersen, Michel Spiro, Andrew Gould |
| المساهمون: | 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), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Niels Bohr Institute [Copenhagen] (NBI), Faculty of Science [Copenhagen], University of Copenhagen = Københavns Universitet (UCPH)-University of Copenhagen = Københavns Universitet (UCPH), Institut d'Astrophysique de Paris (IAP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de l'Observatoire Midi-Pyrénées (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), European Southern Observatory (ESO), Department of Astronomy (Ohio State University), Ohio State University [Columbus] (OSU), 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), Department of Physics [Tehran], Sharif University of Technology [Tehran] (SUT), EROS-2, Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), University of Copenhagen = Københavns Universitet (KU)-University of Copenhagen = Københavns Universitet (KU), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-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), 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) |
| المصدر: | Astronomy and Astrophysics-A&A Astronomy and Astrophysics-A&A, 2009, 500, pp.1027-1044. ⟨10.1051/0004-6361/200811515⟩ Astronomy and Astrophysics-A&A, EDP Sciences, 2009, 500, pp.1027-1044. ⟨10.1051/0004-6361/200811515⟩ |
| بيانات النشر: | HAL CCSD, 2009. |
| سنة النشر: | 2009 |
| مصطلحات موضوعية: | Milky Way, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Gravitational microlensing, 01 natural sciences, Galaxy: bulge, Galaxy: disk, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Bulge, 0103 physical sciences, Thick disk, 010303 astronomy & astrophysics, Galaxy: structure, Astrophysics::Galaxy Astrophysics, Physics, Spiral galaxy, Galaxy: microlensing, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Galactic Center, Astronomy and Astrophysics, Galactic plane, Astrophysics - Astrophysics of Galaxies, Stars, Galaxy: spiral arms, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Cosmology: dark matter, Astrophysics::Earth and Planetary Astrophysics |
| الوصف: | The EROS-2 project has been designed to search for microlensing events towards any dense stellar field. The densest parts of the Galactic spiral arms have been monitored to maximize the microlensing signal expected from the stars of the Galactic disk and bulge. 12.9 million stars have been monitored during 7 seasons towards 4 directions in the Galactic plane, away from the Galactic center. A total of 27 microlensing event candidates have been found. Estimates of the optical depths from the 22 best events are provided. A first order interpretation shows that simple Galactic models with a standard disk and an elongated bulge are in agreement with our observations. We find that the average microlensing optical depth towards the complete EROS-cataloged stars of the spiral arms is $\bar{\tau} =0.51\pm .13\times 10^{-6}$, a number that is stable when the selection criteria are moderately varied. As the EROS catalog is almost complete up to $I_C=18.5$, the optical depth estimated for the sub-sample of bright target stars with $I_C.11\times 10^{-6}$) is easier to interpret. The set of microlensing events that we have observed is consistent with a simple Galactic model. A more precise interpretation would require either a better knowledge of the distance distribution of the target stars, or a simulation based on a Galactic model. For this purpose, we define and discuss the concept of optical depth for a given catalog or for a limiting magnitude. Comment: 22 pages submitted to Astronomy & Astrophysics |
| اللغة: | English |
| تدمد: | 0004-6361 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::e6b56b1d59851108318321de40bf9394 https://hal.in2p3.fr/in2p3-00350440/file/eros-gsa.pdf |
| حقوق: | OPEN |
| رقم الأكسشن: | edsair.doi.dedup.....e6b56b1d59851108318321de40bf9394 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 00046361 |
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