Age dating of an early Milky Way merger via asteroseismology of the naked-eye star ν Indi

William J. Chaplin; Aldo M. Serenelli; Andrea Miglio; Thierry Morel; J. Ted Mackereth; Fiorenzo Vincenzo; Hans Kjeldsen; Sarbani Basu; Warrick H. Ball; Amalie Stokholm; Kuldeep Verma; Jakob Rørsted Mosumgaard; Victor Silva Aguirre; Anwesh Mazumdar; Pritesh Ranadive; H. M. Antia; Yveline Lebreton; Joel Ong; Thierry Appourchaux; Timothy R. Bedding; Jørgen Christensen-Dalsgaard; Orlagh Creevey; Rafael A. García; Rasmus Handberg; Daniel Huber; Steven D. Kawaler; Mikkel N. Lund; Travis S. Metcalfe; Keivan G. Stassun; Michäel Bazot; Paul G. Beck; Keaton J. Bell; Maria Bergemann; Derek L. Buzasi; Othman Benomar; Diego Bossini; Lisa Bugnet; Tiago L. Campante; Zeynep çelik Orhan; Enrico Corsaro; Lucía González-Cuesta; Guy R. Davies; Maria Pia Di Mauro; Ricky Egeland; Yvonne P. Elsworth; Patrick Gaulme; Hamed Ghasemi; Zhao Guo; Oliver J. Hall; Amir Hasanzadeh; Saskia Hekker; Rachel Howe; Jon M. Jenkins; Antonio Jiménez; René Kiefer; James S. Kuszlewicz; Thomas Kallinger; David W. Latham; Mia S. Lundkvist; Savita Mathur; Josefina Montalbán; Benoit Mosser; Andres Moya Bedón; Martin Bo Nielsen; Sibel Örtel; Ben M. Rendle; George R. Ricker; Thaíse S. Rodrigues; Ian W. Roxburgh; Hossein Safari; Mathew Schofield; Sara Seager; Barry Smalley; Dennis Stello; Róbert Szabó; Jamie Tayar; Nathalie Themeßl; Alexandra E. L. Thomas; Roland K. Vanderspek; Walter E. van Rossem; Mathieu Vrard; Achim Weiss; Timothy R. White; Joshua N. Winn; Mutlu Yıldız

doi:10.1038/s41550-019-0975-9

Age dating of an early Milky Way merger via asteroseismology of the naked-eye star ν Indi

William J. Chaplin, Aldo M. Serenelli, Andrea Miglio, Thierry Morel, J. Ted Mackereth, Fiorenzo Vincenzo, Hans Kjeldsen, Sarbani Basu, Warrick H. Ball, Amalie Stokholm, Kuldeep Verma, Jakob Rørsted Mosumgaard, Victor Silva Aguirre, Anwesh Mazumdar, Pritesh Ranadive, H. M. Antia, Yveline Lebreton, Joel Ong, Thierry Appourchaux, Timothy R. BeddingJørgen Christensen-Dalsgaard, Orlagh Creevey, Rafael A. García, Rasmus Handberg, Daniel Huber, Steven D. Kawaler, Mikkel N. Lund, Travis S. Metcalfe, Keivan G. Stassun, Michäel Bazot, Paul G. Beck, Keaton J. Bell, Maria Bergemann, Derek L. Buzasi, Othman Benomar, Diego Bossini, Lisa Bugnet, Tiago L. Campante, Zeynep çelik Orhan, Enrico Corsaro, Lucía González-Cuesta, Guy R. Davies, Maria Pia Di Mauro, Ricky Egeland, Yvonne P. Elsworth, Patrick Gaulme, Hamed Ghasemi, Zhao Guo, Oliver J. Hall, Amir Hasanzadeh, Saskia Hekker, Rachel Howe, Jon M. Jenkins, Antonio Jiménez, René Kiefer, James S. Kuszlewicz, Thomas Kallinger, David W. Latham, Mia S. Lundkvist, Savita Mathur, Josefina Montalbán, Benoit Mosser, Andres Moya Bedón, Martin Bo Nielsen, Sibel Örtel, Ben M. Rendle, George R. Ricker, Thaíse S. Rodrigues, Ian W. Roxburgh, Hossein Safari, Mathew Schofield, Sara Seager, Barry Smalley, Dennis Stello, Róbert Szabó, Jamie Tayar, Nathalie Themeßl, Alexandra E. L. Thomas, Roland K. Vanderspek, Walter E. van Rossem, Mathieu Vrard, Achim Weiss, Timothy R. White, Joshua N. Winn, Mutlu Yıldız

Department of Physics and Astronomy - Stellar Astrophysics Centre

Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Letter › peer-review

52 Citations (Scopus)

Abstract

Over the course of its history, the Milky Way has ingested multiple smaller satellite galaxies1. Although these accreted stellar populations can be forensically identified as kinematically distinct structures within the Galaxy, it is difficult in general to date precisely the age at which any one merger occurred. Recent results have revealed a population of stars that were accreted via the collision of a dwarf galaxy, called Gaia-Enceladus1, leading to substantial pollution of the chemical and dynamical properties of the Milky Way. Here we identify the very bright, naked-eye star ν Indi as an indicator of the age of the early in situ population of the Galaxy. We combine asteroseismic, spectroscopic, astrometric and kinematic observations to show that this metal-poor, alpha-element-rich star was an indigenous member of the halo, and we measure its age to be 11.0 ±0.7 ? (stat) ±0.8 ? (sys) billion years. The star bears hallmarks consistent with having been kinematically heated by the Gaia-Enceladus collision. Its age implies that the earliest the merger could have begun was 11.6 and 13.2 billion years ago, at 68% and 95% confidence, respectively. Computations based on hierarchical cosmological models slightly reduce the above limits.

Original language	English
Journal	Nature Astronomy
Volume	4
Issue	4
Pages (from-to)	382-+
Number of pages	11
DOIs	https://doi.org/10.1038/s41550-019-0975-9
Publication status	Published - Apr 2020

Keywords

ACCRETION HISTORY
CHEMICAL-COMPOSITION
DARK-MATTER HALOES
DISC
GAIA
MASS
MODEL
ROTATION
SOLAR-LIKE OSCILLATIONS
STELLAR HALOES

Access to Document

10.1038/s41550-019-0975-9

Cite this

Chaplin, W. J., Serenelli, A. M., Miglio, A., Morel, T., Mackereth, J. T., Vincenzo, F., Kjeldsen, H., Basu, S., Ball, W. H., Stokholm, A., Verma, K., Mosumgaard, J. R., Silva Aguirre, V., Mazumdar, A., Ranadive, P., Antia, H. M., Lebreton, Y., Ong, J., Appourchaux, T., ... Yıldız, M. (2020). Age dating of an early Milky Way merger via asteroseismology of the naked-eye star ν Indi. Nature Astronomy, 4(4), 382-+. https://doi.org/10.1038/s41550-019-0975-9

@article{b81777557cf144c98af3c503c27bdac1,

title = "Age dating of an early Milky Way merger via asteroseismology of the naked-eye star ν Indi",

abstract = "Over the course of its history, the Milky Way has ingested multiple smaller satellite galaxies1. Although these accreted stellar populations can be forensically identified as kinematically distinct structures within the Galaxy, it is difficult in general to date precisely the age at which any one merger occurred. Recent results have revealed a population of stars that were accreted via the collision of a dwarf galaxy, called Gaia-Enceladus1, leading to substantial pollution of the chemical and dynamical properties of the Milky Way. Here we identify the very bright, naked-eye star ν Indi as an indicator of the age of the early in situ population of the Galaxy. We combine asteroseismic, spectroscopic, astrometric and kinematic observations to show that this metal-poor, alpha-element-rich star was an indigenous member of the halo, and we measure its age to be 11.0 ±0.7 ? (stat) ±0.8 ? (sys) billion years. The star bears hallmarks consistent with having been kinematically heated by the Gaia-Enceladus collision. Its age implies that the earliest the merger could have begun was 11.6 and 13.2 billion years ago, at 68% and 95% confidence, respectively. Computations based on hierarchical cosmological models slightly reduce the above limits.",

keywords = "ACCRETION HISTORY, CHEMICAL-COMPOSITION, DARK-MATTER HALOES, DISC, GAIA, MASS, MODEL, ROTATION, SOLAR-LIKE OSCILLATIONS, STELLAR HALOES",

author = "Chaplin, {William J.} and Serenelli, {Aldo M.} and Andrea Miglio and Thierry Morel and Mackereth, {J. Ted} and Fiorenzo Vincenzo and Hans Kjeldsen and Sarbani Basu and Ball, {Warrick H.} and Amalie Stokholm and Kuldeep Verma and Mosumgaard, {Jakob R{\o}rsted} and {Silva Aguirre}, Victor and Anwesh Mazumdar and Pritesh Ranadive and Antia, {H. M.} and Yveline Lebreton and Joel Ong and Thierry Appourchaux and Bedding, {Timothy R.} and J{\o}rgen Christensen-Dalsgaard and Orlagh Creevey and Garc{\'i}a, {Rafael A.} and Rasmus Handberg and Daniel Huber and Kawaler, {Steven D.} and Lund, {Mikkel N.} and Metcalfe, {Travis S.} and Stassun, {Keivan G.} and Mich{\"a}el Bazot and Beck, {Paul G.} and Bell, {Keaton J.} and Maria Bergemann and Buzasi, {Derek L.} and Othman Benomar and Diego Bossini and Lisa Bugnet and Campante, {Tiago L.} and Orhan, {Zeynep {\c c}elik} and Enrico Corsaro and Luc{\'i}a Gonz{\'a}lez-Cuesta and Davies, {Guy R.} and {Di Mauro}, {Maria Pia} and Ricky Egeland and Elsworth, {Yvonne P.} and Patrick Gaulme and Hamed Ghasemi and Zhao Guo and Hall, {Oliver J.} and Amir Hasanzadeh and Saskia Hekker and Rachel Howe and Jenkins, {Jon M.} and Antonio Jim{\'e}nez and Ren{\'e} Kiefer and Kuszlewicz, {James S.} and Thomas Kallinger and Latham, {David W.} and Lundkvist, {Mia S.} and Savita Mathur and Josefina Montalb{\'a}n and Benoit Mosser and Bed{\'o}n, {Andres Moya} and Nielsen, {Martin Bo} and Sibel {\"O}rtel and Rendle, {Ben M.} and Ricker, {George R.} and Rodrigues, {Tha{\'i}se S.} and Roxburgh, {Ian W.} and Hossein Safari and Mathew Schofield and Sara Seager and Barry Smalley and Dennis Stello and R{\'o}bert Szab{\'o} and Jamie Tayar and Nathalie Theme{\ss}l and Thomas, {Alexandra E. L.} and Vanderspek, {Roland K.} and {van Rossem}, {Walter E.} and Mathieu Vrard and Achim Weiss and White, {Timothy R.} and Winn, {Joshua N.} and Mutlu Yıldız",

year = "2020",

month = apr,

doi = "10.1038/s41550-019-0975-9",

language = "English",

volume = "4",

pages = "382--+",

journal = "Nature Astronomy",

issn = "2397-3366",

publisher = "Nature Publishing Group",

number = "4",

}

Chaplin, WJ, Serenelli, AM, Miglio, A, Morel, T, Mackereth, JT, Vincenzo, F, Kjeldsen, H, Basu, S, Ball, WH, Stokholm, A, Verma, K, Mosumgaard, JR, Silva Aguirre, V, Mazumdar, A, Ranadive, P, Antia, HM, Lebreton, Y, Ong, J, Appourchaux, T, Bedding, TR, Christensen-Dalsgaard, J, Creevey, O, García, RA, Handberg, R, Huber, D, Kawaler, SD, Lund, MN , Metcalfe, TS, Stassun, KG, Bazot, M, Beck, PG, Bell, KJ, Bergemann, M, Buzasi, DL, Benomar, O, Bossini, D, Bugnet, L, Campante, TL, Orhan, ZÇ, Corsaro, E, González-Cuesta, L, Davies, GR, Di Mauro, MP, Egeland, R, Elsworth, YP, Gaulme, P, Ghasemi, H, Guo, Z, Hall, OJ, Hasanzadeh, A, Hekker, S, Howe, R, Jenkins, JM, Jiménez, A, Kiefer, R, Kuszlewicz, JS, Kallinger, T, Latham, DW, Lundkvist, MS, Mathur, S, Montalbán, J, Mosser, B, Bedón, AM, Nielsen, MB, Örtel, S, Rendle, BM, Ricker, GR, Rodrigues, TS, Roxburgh, IW, Safari, H, Schofield, M, Seager, S, Smalley, B, Stello, D, Szabó, R, Tayar, J, Themeßl, N, Thomas, AEL, Vanderspek, RK, van Rossem, WE, Vrard, M, Weiss, A, White, TR, Winn, JN & Yıldız, M 2020, 'Age dating of an early Milky Way merger via asteroseismology of the naked-eye star ν Indi', Nature Astronomy, vol. 4, no. 4, pp. 382-+. https://doi.org/10.1038/s41550-019-0975-9

TY - JOUR

T1 - Age dating of an early Milky Way merger via asteroseismology of the naked-eye star ν Indi

AU - Chaplin, William J.

AU - Serenelli, Aldo M.

AU - Miglio, Andrea

AU - Morel, Thierry

AU - Mackereth, J. Ted

AU - Vincenzo, Fiorenzo

AU - Kjeldsen, Hans

AU - Basu, Sarbani

AU - Ball, Warrick H.

AU - Stokholm, Amalie

AU - Verma, Kuldeep

AU - Mosumgaard, Jakob Rørsted

AU - Silva Aguirre, Victor

AU - Mazumdar, Anwesh

AU - Ranadive, Pritesh

AU - Antia, H. M.

AU - Lebreton, Yveline

AU - Ong, Joel

AU - Appourchaux, Thierry

AU - Bedding, Timothy R.

AU - Christensen-Dalsgaard, Jørgen

AU - Creevey, Orlagh

AU - García, Rafael A.

AU - Handberg, Rasmus

AU - Huber, Daniel

AU - Kawaler, Steven D.

AU - Lund, Mikkel N.

AU - Metcalfe, Travis S.

AU - Stassun, Keivan G.

AU - Bazot, Michäel

AU - Beck, Paul G.

AU - Bell, Keaton J.

AU - Bergemann, Maria

AU - Buzasi, Derek L.

AU - Benomar, Othman

AU - Bossini, Diego

AU - Bugnet, Lisa

AU - Campante, Tiago L.

AU - Orhan, Zeynep çelik

AU - Corsaro, Enrico

AU - González-Cuesta, Lucía

AU - Davies, Guy R.

AU - Di Mauro, Maria Pia

AU - Egeland, Ricky

AU - Elsworth, Yvonne P.

AU - Gaulme, Patrick

AU - Ghasemi, Hamed

AU - Guo, Zhao

AU - Hall, Oliver J.

AU - Hasanzadeh, Amir

AU - Hekker, Saskia

AU - Howe, Rachel

AU - Jenkins, Jon M.

AU - Jiménez, Antonio

AU - Kiefer, René

AU - Kuszlewicz, James S.

AU - Kallinger, Thomas

AU - Latham, David W.

AU - Lundkvist, Mia S.

AU - Mathur, Savita

AU - Montalbán, Josefina

AU - Mosser, Benoit

AU - Bedón, Andres Moya

AU - Nielsen, Martin Bo

AU - Örtel, Sibel

AU - Rendle, Ben M.

AU - Ricker, George R.

AU - Rodrigues, Thaíse S.

AU - Roxburgh, Ian W.

AU - Safari, Hossein

AU - Schofield, Mathew

AU - Seager, Sara

AU - Smalley, Barry

AU - Stello, Dennis

AU - Szabó, Róbert

AU - Tayar, Jamie

AU - Themeßl, Nathalie

AU - Thomas, Alexandra E. L.

AU - Vanderspek, Roland K.

AU - van Rossem, Walter E.

AU - Vrard, Mathieu

AU - Weiss, Achim

AU - White, Timothy R.

AU - Winn, Joshua N.

AU - Yıldız, Mutlu

PY - 2020/4

Y1 - 2020/4

N2 - Over the course of its history, the Milky Way has ingested multiple smaller satellite galaxies1. Although these accreted stellar populations can be forensically identified as kinematically distinct structures within the Galaxy, it is difficult in general to date precisely the age at which any one merger occurred. Recent results have revealed a population of stars that were accreted via the collision of a dwarf galaxy, called Gaia-Enceladus1, leading to substantial pollution of the chemical and dynamical properties of the Milky Way. Here we identify the very bright, naked-eye star ν Indi as an indicator of the age of the early in situ population of the Galaxy. We combine asteroseismic, spectroscopic, astrometric and kinematic observations to show that this metal-poor, alpha-element-rich star was an indigenous member of the halo, and we measure its age to be 11.0 ±0.7 ? (stat) ±0.8 ? (sys) billion years. The star bears hallmarks consistent with having been kinematically heated by the Gaia-Enceladus collision. Its age implies that the earliest the merger could have begun was 11.6 and 13.2 billion years ago, at 68% and 95% confidence, respectively. Computations based on hierarchical cosmological models slightly reduce the above limits.

AB - Over the course of its history, the Milky Way has ingested multiple smaller satellite galaxies1. Although these accreted stellar populations can be forensically identified as kinematically distinct structures within the Galaxy, it is difficult in general to date precisely the age at which any one merger occurred. Recent results have revealed a population of stars that were accreted via the collision of a dwarf galaxy, called Gaia-Enceladus1, leading to substantial pollution of the chemical and dynamical properties of the Milky Way. Here we identify the very bright, naked-eye star ν Indi as an indicator of the age of the early in situ population of the Galaxy. We combine asteroseismic, spectroscopic, astrometric and kinematic observations to show that this metal-poor, alpha-element-rich star was an indigenous member of the halo, and we measure its age to be 11.0 ±0.7 ? (stat) ±0.8 ? (sys) billion years. The star bears hallmarks consistent with having been kinematically heated by the Gaia-Enceladus collision. Its age implies that the earliest the merger could have begun was 11.6 and 13.2 billion years ago, at 68% and 95% confidence, respectively. Computations based on hierarchical cosmological models slightly reduce the above limits.

KW - ACCRETION HISTORY

KW - CHEMICAL-COMPOSITION

KW - DARK-MATTER HALOES

KW - DISC

KW - GAIA

KW - MASS

KW - MODEL

KW - ROTATION

KW - SOLAR-LIKE OSCILLATIONS

KW - STELLAR HALOES

UR - http://www.scopus.com/inward/record.url?scp=85078042459&partnerID=8YFLogxK

U2 - 10.1038/s41550-019-0975-9

DO - 10.1038/s41550-019-0975-9

M3 - Letter

SN - 2397-3366

VL - 4

SP - 382-+

JO - Nature Astronomy

JF - Nature Astronomy

IS - 4

ER -

Age dating of an early Milky Way merger via asteroseismology of the naked-eye star ν Indi

Abstract

Keywords

Access to Document

Other files and links

Fingerprint

Cite this