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1. Erratum: The Pristine survey – VI: The first three years of medium-resolution follow-up spectroscopy of Pristine EMP star candidates (Monthly Notices of the Royal Astronomical Society (2019) 490 (2241-2253) DOI: 10.1093/mnras/stz2643)

Author

Aguado D. S., Youakim K., Gonzalez Hernandez J. I., Prieto C. A., Starkenburg E., Martin N., Bonifacio P., Arentsen A., Caffau E., Peralta de Arriba L., Sestito F., Garcia-Dias R., Fantin N., Hill V., Jablonca P., Jahandar F., Kielty C., Longeard N., Lucchesi R., Sanchez-Janssen R., Osorio Y., Palicio P. A., Tolstoy E., Wilson T. G., Cote P., Kordopatis G., Lardo C., Navarro J. F., Thomas G. F., Venn K., Aguado D.S., Youakim K., Gonzalez Hernandez J.I., Prieto C.A., Starkenburg E., Martin N., Bonifacio P., Arentsen A., Caffau E., Peralta de Arriba L., Sestito F., Garcia-Dias R., Fantin N., Hill V., Jablonca P., Jahandar F., Kielty C., Longeard N., Lucchesi R., Sanchez-Janssen R., Osorio Y., Palicio P.A., Tolstoy E., Wilson T.G., Cote P., Kordopatis G., Lardo C., Navarro J.F., Thomas G.F., and Venn K.

Subjects
metallicity distribution
Published
2020

2. The Pristine Inner Galaxy Survey (PIGS) I : tracing the kinematics of metal-poor stars in the Galactic bulge

Author

Arentsen, A., Starkenburg, E., Martin, N. F., Hill, V., Ibata, R., Kunder, A., Schultheis, M., Venn, K. A., Zucker, D. B., Aguado, D., Carlberg, R., González Hernández, J., Lardo, C., Longeard, N., Malhan, Khyati, Navarro, J. F., Sánchez-Janssen, R., Sestito, F., Thomas, G., Youakim, K., Lewis, G. F., Simpson, J. D., Wan, Z., Arentsen, A., Starkenburg, E., Martin, N. F., Hill, V., Ibata, R., Kunder, A., Schultheis, M., Venn, K. A., Zucker, D. B., Aguado, D., Carlberg, R., González Hernández, J., Lardo, C., Longeard, N., Malhan, Khyati, Navarro, J. F., Sánchez-Janssen, R., Sestito, F., Thomas, G., Youakim, K., Lewis, G. F., Simpson, J. D., and Wan, Z.

Abstract

Our Galaxy is known to contain a central boxy/peanut-shaped bulge, yet the importance of a classical, pressure-supported component within the central part of the Milky Way is still being debated. It should be most visible at low metallicity, a regime that has not yet been studied in detail. Using metallicity-sensitive narrow-band photometry, the Pristine Inner Galaxy Survey (PIGS) has collected a large sample of metal-poor ([Fe/H] < -1.0) stars in the inner Galaxy to address this open question. We use PIGS to trace the metal-poor inner Galaxy kinematics as function of metallicity for the first time. We find that the rotational signal decreases with decreasing [Fe/H], until it becomes negligible for the most metal-poor stars. Additionally, the velocity dispersion increases with decreasing metallicity for -3.0 < [Fe/II] < -0.5, with a gradient of -44 +/- 41un s(-1)dex(-1). These observations may signal a transition between Galactic components of different metallicities and kinematics, a different mapping on to the boxy/peanut-shaped bulge for former disc stars of different metallicities and/or the secular dynamical and gravitational influence of the bar on the pressure-supported component. Our results provide strong constraints on models that attempt to explain the properties of the inner Galaxy.

Published
2020
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3. The Pristine Inner Galaxy Survey (PIGS) I: Tracing the kinematics of metal-poor stars in the Galactic bulge

Author

Arentsen, A, Starkenburg, E, Martin, NF, Hill, V, Ibata, R, Kunder, A, Schultheis, M, Venn, KA, Zucker, DB, Aguado, D, Carlberg, R, González Hernández, JI, Lardo, C, Longeard, N, Malhan, K, Navarro, JF, Sánchez-Janssen, R, Sestito, F, Thomas, G, Youakim, K, Lewis, GF, Simpson, JD ; https://orcid.org/0000-0002-8165-2507, Wan, Z, Arentsen, A, Starkenburg, E, Martin, NF, Hill, V, Ibata, R, Kunder, A, Schultheis, M, Venn, KA, Zucker, DB, Aguado, D, Carlberg, R, González Hernández, JI, Lardo, C, Longeard, N, Malhan, K, Navarro, JF, Sánchez-Janssen, R, Sestito, F, Thomas, G, Youakim, K, Lewis, GF, Simpson, JD ; https://orcid.org/0000-0002-8165-2507, and Wan, Z

Abstract

Our Galaxy is known to contain a central boxy/peanut-shaped bulge, yet the importance of a classical, pressure-supported component within the central part of the Milky Way is still being debated. It should be most visible at low metallicity, a regime that has not yet been studied in detail. Using metallicity-sensitive narrow-band photometry, the Pristine Inner Galaxy Survey (PIGS) has collected a large sample of metal-poor ([Fe/H]<-1.0$) stars in the inner Galaxy to address this open question. We use PIGS to trace the metal-poor inner Galaxy kinematics as function of metallicity for the first time. We find that the rotational signal decreases with decreasing [Fe/H], until it becomes negligible for the most metal-poor stars. Additionally, the velocity dispersion increases with decreasing metallicity for $-3.0<[Fe/H]<-0.5, with a gradient of-44 ± 4 km s-1 dex-1. These observations may signal a transition between Galactic components of different metallicities and kinematics, a different mapping on to the boxy/peanut-shaped bulge for former disc stars of different metallicities and/or the secular dynamical and gravitational influence of the bar on the pressure-supported component. Our results provide strong constraints on models that attempt to explain the properties of the inner Galaxy.

Published
2020

4. The Pristine Inner Galaxy Survey (PIGS) I: tracing the kinematics of metal-poor stars in the Galactic bulge

Author

Arentsen, A, primary, Starkenburg, E, additional, Martin, N F, additional, Hill, V, additional, Ibata, R, additional, Kunder, A, additional, Schultheis, M, additional, Venn, K A, additional, Zucker, D B, additional, Aguado, D, additional, Carlberg, R, additional, González Hernández, J I, additional, Lardo, C, additional, Longeard, N, additional, Malhan, K, additional, Navarro, J F, additional, Sánchez-Janssen, R, additional, Sestito, F, additional, Thomas, G, additional, Youakim, K, additional, Lewis, G F, additional, Simpson, J D, additional, and Wan, Z, additional

Published
2019
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5. The Pristine survey IV: approaching the Galactic metallicity floor with the discovery of an ultra-metal-poor star

Author

Piercarlo Bonifacio, D. S. Aguado, A. Arentsen, Eline Tolstoy, Rubén Sánchez-Janssen, Patrick Côté, Elisabetta Caffau, Kim A. Venn, Vanessa Hill, Julio F. Navarro, Nicolas Longeard, Carlos Allende Prieto, Morgan Fouesneau, Pascale Jablonka, Raymond G. Carlberg, Marc Gentile, Federico Sestito, Else Starkenburg, Collin Kielty, Helmer H. Koppelman, Jonay I. González Hernández, Nicolas F. Martin, Kris Youakim, Carmela Lardo, Alan W. McConnachie, Astronomy, Starkenburg E., Aguado D.S., Bonifacio P., Caffau E., Jablonka P., Lardo C., Martin N., Sanchez-Janssen R., Sestito F., Venn K.A., Youakim K., Prieto C.A., Arentsen A., Gentile M., Hernandez J.I.G., Kielty C., Koppelman H.H., Longeard N., Tolstoy E., Carlberg R.G., Cote P., Fouesneau M., Hill V., McConnachie A.W., Navarro J.F., Galaxies, Etoiles, Physique, Instrumentation (GEPI), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies (UMR 6174) (FEMTO-ST), Université de Technologie de Belfort-Montbeliard (UTBM)-Ecole Nationale Supérieure de Mécanique et des Microtechniques (ENSMM)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS), National Research Council of Canada (NRC), 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), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
photometry, stars: abundances, Metallicity, media_common.quotation_subject, 1st stars, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, telescope, Star (graph theory), 01 natural sciences, Galactic halo, Metal, hamburg/eso survey, 0103 physical sciences, Galaxy formation and evolution, Astrophysics::Solar and Stellar Astrophysics, 010306 general physics, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, media_common, [PHYS]Physics [physics], Physics, Galaxy: evolution, abundance, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Astronomy and Astrophysics, stars: abundances, Galaxy: abundances, Galaxy: evolution, Galaxy: formation, Galaxy: halo, Astrophysics - Solar and Stellar Astrophysics, Astrophysics - Astrophysics of Galaxies, model atmospheres, Astrophysics - Astrophysics of Galaxies, chemical-compositions, Universe, sky survey, Galaxy: halo, Galaxy: abundance, Stars, Astrophysics - Solar and Stellar Astrophysics, lithium, 13. Climate action, Space and Planetary Science, Galaxy: formation, Astrophysics of Galaxies (astro-ph.GA), visual_art, visual_art.visual_art_medium, Galaxy: abundances, Astrophysics::Earth and Planetary Astrophysics, halo-stars
Abstract

The early Universe presented a star formation environment that was almost devoid of heavy elements. The lowest metallicity stars thus provide a unique window into the earliest Galactic stages, but are exceedingly rare and difficult to find. Here we present the discovery of an ultra-metal-poor star, Pristine_221.8781+9.7844, using narrow-band Ca H&K photometry from the Pristine survey. Follow-up medium and high-resolution spectroscopy confirms the ultra-metal-poor nature of Pristine_221.8781+9.7844 ([Fe/H] = -4.66 +/- 0.13 in 1D LTE) with an enhancement of 0.3-0.4 dex in alpha-elements relative to Fe, and an unusually low carbon abundance. We derive an upper limit of A(C) = 5.6, well below typical A(C) values for such ultra metal-poor stars. This makes Pristine_221.8781+9.7844 one of the most metal-poor stars; in fact, it is very similar to the most metal-poor star known (SDSS J102915+172927). The existence of a class of ultra metal-poor stars with low(er) carbon abundances suggest that there must have been several formation channels in the early Universe through which long-lived, low-mass stars were formed., Re-submitted to MNRAS after minor revisions

Published
2018
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6. The Pristine Inner Galaxy Survey (PIGS) I: Tracing the kinematics of metal-poor stars in the Galactic bulge

Author

Mathias Schultheis, Jeffrey D. Simpson, Zhen Wan, Anke Arentsen, G. F. Thomas, Nicolas F. Martin, K. A. Venn, Rodrigo A. Ibata, K. Youakim, Daniel B. Zucker, Nicolas Longeard, J. I. González Hernández, Vanessa Hill, Julio F. Navarro, Andrea Kunder, R. G. Carlberg, Carmela Lardo, Khyati Malhan, Geraint F. Lewis, Rubén Sánchez-Janssen, David Aguado, Federico Sestito, Else Starkenburg, Arentsen A., Starkenburg E., Martin N.F., Hill V., Ibata R., Kunder A., Schultheis M., Venn K.A., Zucker D.B., Aguado D., Carlberg R., Gonzalez Hernandez J.I., Lardo C., Longeard N., Malhan K., Navarro J.F., Sanchez-Janssen R., Sestito F., Thomas G., Youakim K., Lewis G.F., Simpson J.D., Wan Z., Observatoire astronomique de Strasbourg (ObAS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Nice, France., Centre International de Hautes Etudes Agronomiques Méditerranéennes - Institut Agronomique Méditerranéen de Montpellier (CIHEAM-IAMM), Centre International de Hautes Études Agronomiques Méditerranéennes (CIHEAM), Laboratoire de Cosmologie, Astrophysique Stellaire & Solaire, de Planétologie et de Mécanique des Fluides (CASSIOPEE), Université Nice Sophia Antipolis (... - 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, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire de la Côte d'Azur (OCA), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), University of Toronto, Ecole Polytechnique Fédérale de Lausanne (EPFL), Facultad de Matematicas, Universidad de Murcia, CLRC Daresbury, SFTC, Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), and COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)

Subjects
photometry, Milky Way, Metallicity, bulge -Galaxy, kinematics and dynamics -Galaxy, formation -Galaxy, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Galaxy: Structure, Galactic halo, Galaxy: Evolution, Bulge, 0103 physical sciences, Galaxy formation and evolution, structure, 010303 astronomy & astrophysics, Galaxy: Halo, halo -Galaxy, milky-way, ComputingMilieux_MISCELLANEOUS, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, Physics, Galaxy: Kinematics and dynamic, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], stellar populations, Velocity dispersion, Astronomy and Astrophysics, Galaxy: Formation, argos, Galaxy: Bulge, Astrophysics - Astrophysics of Galaxies, Galaxy, evolution -Galaxy, [SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], Stars, [PHYS.ASTR.GA]Physics [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA], Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), galaxy: kinematics and dynamics, [SDU.ASTR.GA]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA], [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

Our Galaxy is known to contain a central boxy/peanut-shaped bulge, yet the importance of a classical, pressure-supported component within the central part of the Milky Way is still being debated. It should be most visible at low metallicity, a regime that has not yet been studied in detail. Using metallicity-sensitive narrow-band photometry, the Pristine Inner Galaxy Survey (PIGS) has collected a large sample of metal-poor ([Fe/H] < -1.0) stars in the inner Galaxy to address this open question. We use PIGS to trace the metal-poor inner Galaxy kinematics as function of metallicity for the first time. We find that the rotational signal decreases with decreasing [Fe/H], until it becomes negligible for the most metal-poor stars. Additionally, the velocity dispersion increases with decreasing metallicity for -3.0 < [Fe/H] < -0.5, with a gradient of -44 $\pm$ 4 km$\,$s$^{-1}\,$dex$^{-1}$. These observations may signal a transition between Galactic components of different metallicities and kinematics, a different mapping onto the boxy/peanut-shaped bulge for former disk stars of different metallicities and/or the secular dynamical and gravitational influence of the bar on the pressure-supported component. Our results provide strong constraints on models that attempt to explain the properties of the inner Galaxy., 5 pages + appendices, accepted to MNRAS Letters

Published
2020
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7. The Pristine survey VI. The first three years of medium-resolution follow-up spectroscopy of Pristine EMP star candidates

Author

Carmela Lardo, K. Youakim, Nicolas F. Martin, Rafael Garcia-Dias, Thomas G. Wilson, Luis Peralta de Arriba, Julio F. Navarro, Vanessa Hill, Pascale Jablonca, Pedro A. Palicio, Georges Kordopatis, Nicholas J. Fantin, Federico Sestito, Carlos Allende Prieto, Else Starkenburg, R. Lucchesi, Jonay I. González Hernández, Yeisson Osorio, Farbod Jahandar, Kim A. Venn, Rubén Sánchez-Janssen, David Aguado, Nicolas Longeard, Anke Arentsen, Collin Kielty, Elisabetta Caffau, Guillaume F. Thomas, Patrick Côté, Eline Tolstoy, Piercarlo Bonifacio, Institute of Astronomy, University of Cambridge, Universidad de La Laguna [Tenerife - SP] (ULL), Leibniz Institute for Astrophysics Potsdam (AIP), 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), Cosmological Impact of the First Stars (CIFIST), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Galaxies, Etoiles, Physique, Instrumentation (GEPI), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Peralta de Arriba, Luis [0000-0002-3084-084X], Apollo - University of Cambridge Repository, Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Astronomy, Aguado D.S., Youakim K., Gonzalez Hernandez J.I., Prieto C.A., Starkenburg E., Martin N., Bonifacio P., Arentsen A., Caffau E., de Arriba L.P., Sestito F., Garcia-Dias R., Fantin N., Hill V., Jablonca P., Jahandar F., Kielty C., Longeard N., Lucchesi R., Sanchez-Janssen R., Osorio Y., Palicio P.A., Tolstoy E., Wilson T.G., Cote P., Kordopatis G., Lardo C., Navarro J.F., Thomas G.F., and Venn K.

Subjects
stars: abundances, galaxy: evolution, Milky Way, first stars, Dark age, halo, FOS: Physical sciences, Astrophysics, 01 natural sciences, local group, galaxy: formation, First star, 0103 physical sciences, evolution, Galaxy formation and evolution, William Herschel Telescope, dark ages, reionization, first stars, metal-poor stars, dark ages, Spectroscopy, 010303 astronomy & astrophysics, Reionization, ComputingMilieux_MISCELLANEOUS, milky-way, Physics, [PHYS]Physics [physics], search, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, abundances, carbon, Astronomy and Astrophysics, oldest, Astrophysics - Astrophysics of Galaxies, early universe, Medium resolution, Stars, classification, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), reionization, discovery
Abstract

We present the results of a 3-year long, medium-resolution spectroscopic campaign aimed at identifying very metal-poor stars from candidates selected with the CaHK, metallicity-sensitive Pristine survey. The catalogue consists of a total of 1007 stars, and includes 146 rediscoveries of metal-poor stars already presented in previous surveys, 707 new very metal-poor stars with [Fe/H] < -2.0, and 95 new extremely metal-poor stars with [Fe/H] < -3.0. We provide a spectroscopic [Fe/H] for every star in the catalogue, and [C/Fe] measurements for a subset of the stars (10% with [Fe/H] < -3 and 24% with -3 < [Fe/H] < -2) for which a carbon determination is possible, contingent mainly on the carbon abundance, effective temperature and S/N of the stellar spectra. We find an average carbon enhancement fraction ([C/Fe] >= +0.7) of 41 +- 4% for stars with -3 < [Fe/H] < -2 and 58 +- 14% for stars with [Fe/H] < -3, and report updated success rates for the Pristine survey of 56 % and 23 % to recover stars with [Fe/H] < -2.5 and [Fe/H] < -3, respectively. Finally, we discuss the current status of the survey and its preparation for providing targets to upcoming multi-object spectroscopic surveys such as WEAVE., 13 pages 6 figures, accepted for publication in MNRAS

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