Hostname: page-component-cd9895bd7-7cvxr Total loading time: 0 Render date: 2024-12-25T16:42:54.141Z Has data issue: false hasContentIssue false

The Prevalence of the α-bimodality: First JWST α-abundance Results in M31

Published online by Cambridge University Press:  13 February 2024

David L. Nidever*
Affiliation:
Department of Physics, Montana State University, P.O. Box 173840, Bozeman, MT 59717-3840, USA.
Karoline Gilbert
Affiliation:
Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA
Erik Tollerud
Affiliation:
Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA
Charles Siders
Affiliation:
Department of Physics, Montana State University, P.O. Box 173840, Bozeman, MT 59717-3840, USA.
Ivanna Escala
Affiliation:
Princeton University, 4 Ivy Lane, Princeton, NJ 08544, USA The Observatories of the Carnegie Institution for Science, 813 Santa Barbara St., Pasadena, CA 91101, USA
Carlos Allende Prieto
Affiliation:
Instituto de Astrofsica de Canarias, E-38205 La Laguna, Tenerife, Spain Departamento de Astrofsica, Universidad de La Laguna (ULL), E-38206 La Laguna, Tenerife, Spain
Verne Smith
Affiliation:
NSF’s National Optical-Infrared Astronomy Research Laboratory, 950 North Cherry Avenue, Tucson, AZ 85719, USA Institut d’Astrophysique de Paris, UMR 7095 CNRS, Sorbonne Université, 98bis Bd. Arago, 75014 Paris, France
Katia Cunha
Affiliation:
Institut d’Astrophysique de Paris, UMR 7095 CNRS, Sorbonne Université, 98bis Bd. Arago, 75014 Paris, France Observatório Nacional, Rua General José Cristino, 77, 20921-400 São Cristóvão, Rio de Janeiro, RJ, Brazil Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ, 85721, USA
Victor P. Debattista
Affiliation:
Jeremiah Horrocks Institute, University of Central Lancashire, Preston, PR1 2HE, UK
Yuan-Sen Ting
Affiliation:
Research School of Astronomy & Astrophysics, Australian National University, Cotter Rd., Weston, ACT 2611, Australia Research School of Computer Science, Australian National University, Acton, ACT 2601, Australia
Evan N. Kirby
Affiliation:
Department of Physics and Astronomy, University of Notre Dame, 225 Nieuwland Science Hall, Notre Dame, IN 46556, USA
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

We present initial results from our JWST NIRSpec program to study the α-abundances in the M31 disk. The Milky Way has two chemically-defined disks, the low-α and high-α disks, which are closely related to the thin and thick disks, respectively. The origin of the two populations and the α-bimodality between them is not entirely clear, although there are now several models that can reproduce the observed features. To help constrain the models and discern the origin, we have undertaken a study of the chemical abundances of the M31 disk using JWST NIRSpec, in order to determine whether stars in M31’s disk also show an α-abundance bimodality. Approximately 100 stars were observed in our single NIRSpec field at a projected distance of 18 kpc from the M31 center. The 1-D extracted spectra have an average signal-to-noise ratio of 85 leading to statistical metallicity precision of 0.016 dex, α-abundance precision of 0.012 dex, and a radial velocity precision 8 km s-1 (mostly from systematics). The initial results indicate that, in contrast to the Milky Way, there is no α-bimodality in the M31 disk, and no low-α sequence. The entire stellar population falls along a single chemical sequence very similar to the MW’s high-α component which had a high star formation rate. While this is somewhat unexpected, the result is not that surprising based on other studies that found the M31 disk has a larger velocity dispersion than the MW and is dominated by a thick component. M31 has had a more active accretion and merger history than the MW which might explain the chemical differences.

Type
Contributed Paper
Creative Commons
Creative Common License - CCCreative Common License - BY
This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, distribution and reproduction, provided the original article is properly cited.
Copyright
© The Author(s), 2024. Published by Cambridge University Press on behalf of International Astronomical Union

References

Allende-Prieto, C. & Team, A. 2023, Astrophysics Source Code Library. ascl:2301.016Google Scholar
Barth, N. A., Gerber, J. M., Boberg, O. M., et al. 2020, MNRAS, 494, 4548. doi: 10.1093/mnras/staa1019 CrossRefGoogle Scholar
Bland-Hawthorn, J. & Gerhard, O. 2016, ARA&A, 54, 529. doi: 10.1146/annurev-astro-081915-023441 CrossRefGoogle Scholar
Bovy, J., Nidever, D. L., Rix, H.-W., et al. 2014, ApJ, 790, 127. doi: 10.1088/0004-637X/790/2/127 Google Scholar
Buck, T. 2020, MNRAS, 491, 5435. doi: 10.1093/mnras/stz3289 CrossRefGoogle Scholar
Casey, A. R., Hogg, D. W., Ness, M., et al. 2016, arXiv:1603.03040. doi: 10.48550/arXiv.1603.03040 CrossRefGoogle Scholar
Chiappini, C., Matteucci, F., & Gratton, R. 1997, ApJ, 477, 765.Google Scholar
Clarke, A. J., Debattista, V. P., Nidever, D. L., et al. 2019, MNRAS, 484, 3476.Google Scholar
Dalcanton, J. J., Bell, E. F., Choi, Y., et al. 2023, arXiv:2304.08613. doi: 10.48550/arXiv.2304.08613 CrossRefGoogle Scholar
D’Souza, R. & Bell, E. F. 2018, Nature Astronomy, 2, 737. doi: 10.1038/s41550-018-0533-x Google Scholar
Donor, J., Frinchaboy, P. M., Cunha, K., et al. 2020, AJ, 159, 199. doi: 10.3847/1538-3881/ab77bc CrossRefGoogle Scholar
Dorman, C. E., Guhathakurta, P., Seth, A. C., et al. 2015, ApJ, 803, 24. doi: 10.1088/0004-637X/803/1/24 CrossRefGoogle Scholar
Escala, I., Kirby, E. N., Gilbert, K. M., et al. 2019, ApJ, 878, 42. doi: 10.3847/1538-4357/ab1eac CrossRefGoogle Scholar
Escala, I., Gilbert, K. M., Kirby, E. N., et al. 2020, ApJ, 889, 177. doi: 10.3847/1538-4357/ab6659 CrossRefGoogle Scholar
Escala, I., Kirby, E. N., Gilbert, K. M., et al. 2020, ApJ, 902, 51. doi: 10.3847/1538-4357/abb474 Google Scholar
Escala, I., Gilbert, K. M., Wojno, J., et al. 2021, AJ, 162, 45. doi: 10.3847/1538-3881/abfec4 CrossRefGoogle Scholar
Escala, I., Quirk, A. C. N., Guhathakurta, P., et al. 2023, AJ, 165, 75. doi: 10.3847/1538-3881/aca9cd CrossRefGoogle Scholar
Fuhrmann, K. 1998, A&A, 338, 161 Google Scholar
Fuhrmann, K. 2011, MNRAS, 414, 2893. doi: 10.1111/j.1365-2966.2011.18476.x CrossRefGoogle Scholar
Collaboration, Gaia, Brown, A. G. A., Vallenari, A., et al. 2021, A&A, 649, A1.Google Scholar
Gilbert, K. M., Kirby, E. N., Escala, I., et al. 2019, ApJ, 883, 128. doi: 10.3847/1538-4357/ab3807 CrossRefGoogle Scholar
Gilbert, K. M., Wojno, J., Kirby, E. N., et al. 2020, AJ, 160, 41. doi: 10.3847/1538-3881/ab9602 CrossRefGoogle Scholar
Gilmore, G. & Reid, N. 1983, MNRAS, 202, 1025. doi: 10.1093/mnras/202.4.1025 CrossRefGoogle Scholar
Gregersen, D., Seth, A. C., Williams, B. F., et al. 2015, AJ, 150, 189. doi: 10.1088/0004-6256/150/6/189 Google Scholar
Hammer, F., Yang, Y. B., Wang, J. L., et al. 2018, MNRAS, 475, 2754. doi: 10.1093/mnras/stx3343 CrossRefGoogle Scholar
Hayden, M. R., Bovy, J., Holtzman, J. A., et al. 2015, ApJ, 808, 132.Google Scholar
Haywood, M., Lehnert, M. D., Di Matteo, P., et al. 2016, A&A, 589, A66.Google Scholar
Hubeny, I. & Lanz, T. 2017, arXiv:1706.01859. doi: 10.48550/arXiv.1706.01859 CrossRefGoogle Scholar
Ibata, R., Irwin, M., Lewis, G., et al. 2001, Nature, 412, 49. doi: 10.1038/35083506 CrossRefGoogle Scholar
Khoperskov, S., Haywood, M., Snaith, O., et al. 2021, MNRAS, 501, 5176. doi: 10.1093/mnras/staa3996 CrossRefGoogle Scholar
Kirby, E. N., Gilbert, K. M., Escala, I., et al. 2020, AJ, 159, 46. doi: 10.3847/1538-3881/ab5f0f CrossRefGoogle Scholar
Kurucz, R. L., 2005, Memorie della Societa Astronomica Italiana Supplementi, 8, 14Google Scholar
Mackereth, J. T., Crain, R. A., Schiavon, R. P., et al. 2018, MNRAS, 477, 5072.Google Scholar
Majewski, S. R., Schiavon, R. P., Frinchaboy, P. M., et al. 2017, AJ, 154, 94. doi: 10.3847/1538-3881/aa784d CrossRefGoogle Scholar
Nidever, D. L., Bovy, J., Bird, J. C., et al. 2014, ApJ, 796, 38. doi: 10.1088/0004-637X/796/1/38 CrossRefGoogle Scholar
Nidever, D. L., Holtzman, J. A., Allende Prieto, C., et al. 2015, AJ, 150, 173. doi: 10.1088/0004-6256/150/6/173 CrossRefGoogle Scholar
Nidever, D. 2021, 10.5281/zenodo.4906681 Google Scholar
Peña, M. & Flores-Durán, S. N. 2019, RMxAA, 55, 255. doi: 10.22201/ia.01851101p.2019.55.02.13 Google Scholar
Reddy, B. E., Lambert, D. L., & Allende Prieto, C. 2006, MNRAS, 367, 1329. doi: 10.1111/j.1365-2966.2006.10148.x CrossRefGoogle Scholar
Rigby, J., Perrin, M., McElwain, M., et al. 2023, PASP, 135, 048001. doi: 10.1088/1538-3873/acb293 CrossRefGoogle Scholar
Schönrich, R., & Binney, J. 2009, MNRAS, 396, 203.Google Scholar
Sellwood, J. A. & Binney, J. J. 2002, MNRAS, 336, 785. doi: 10.1046/j.1365-8711.2002.05806.x CrossRefGoogle Scholar
Sharma, S., Hayden, M. R., & Bland-Hawthorn, J. 2021, MNRAS, 507, 5882. doi: 10.1093/mnras/stab2015 CrossRefGoogle Scholar
Solway, M., Sellwood, J. A., & Schönrich, R. 2012, MNRAS, 422, 1363. doi: 10.1111/j.1365-2966.2012.20712.x CrossRefGoogle Scholar
Ting, Y.-S., Conroy, C., Rix, H.-W., et al. 2017, ApJ, 843, 32. doi: 10.3847/1538-4357/aa7688 CrossRefGoogle Scholar
Wilson, J. C., Hearty, F. R., Skrutskie, M. F., et al. 2019, PASP, 131, 055001. doi: 10.1088/1538-3873/ab0075 CrossRefGoogle Scholar
Wojno, J., Gilbert, K. M., Kirby, E. N., et al. 2020, ApJ, 895, 78. doi: 10.3847/1538-4357/ab8ccb CrossRefGoogle Scholar
Wojno, J. L., Gilbert, K. M., Kirby, E. N., et al. 2022, arXiv:2211.15288. doi: 10.48550/arXiv.2211.15288 CrossRefGoogle Scholar
Yoshii, Y. 1982, PASJ, 34, 365 CrossRefGoogle Scholar