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Title: Stellar population models based on the SDSS-IV MaStar library of stellar spectra – I. Intermediate-age/old models

Abstract

ABSTRACT We use the first release of the SDSS/MaStar stellar library comprising ∼9000, high S/N spectra, to calculate integrated spectra of stellar population models. The models extend over the wavelength range 0.36–1.03 µm and share the same spectral resolution ($$R\sim 1800$$) and flux calibration as the SDSS-IV/MaNGA galaxy data. The parameter space covered by the stellar spectra collected thus far allows the calculation of models with ages and chemical composition in the range $$\rm {\mathit{ t}\gt 200 \,Myr, -2 \lt = [Z/H] \lt = + 0.35}$$, which will be extended as MaStar proceeds. Notably, the models include spectra for dwarf main-sequence stars close to the core H-burning limit, as well as spectra for cold, metal-rich giants. Both stellar types are crucial for modelling λ > 0.7 µm absorption spectra. Moreover, a better parameter coverage at low metallicity allows the calculation of models as young as 500 Myr and the full account of the blue horizontal branch phase of old populations. We present models adopting two independent sets of stellar parameters (Teff, log g, [Z/H]). In a novel approach, their reliability is tested ‘on the fly’ using the stellar population models themselves. We perform tests with Milky Way and Magellanic Clouds globular clusters, finding that the new models recover their ages and metallicities remarkably well, with systematics as low as a few per cent for homogeneous calibration sets. We also fit a MaNGA galaxy spectrum, finding residuals of the order of a few per cent comparable to the state-of-art models, but now over a wider wavelength range.

Authors:
 [1];  [1]; ORCiD logo [1];  [2];  [3];  [4];  [5];  [1];  [1];  [6];  [7];  [8];  [9];  [10];  [2];  [11];  [12]
  1. Institute of Cosmology, University of Portsmouth, Burnaby Road, Portsmouth PO1 3FX, UK
  2. Department of Physics and Astronomy, University of Kentucky, 505 Rose St., Lexington, KY 40506-0057, USA
  3. New York University Abu Dhabi, Abu Dhabi, PO Box 129188, United Arab Emirates
  4. Institute of Cosmology, University of Portsmouth, Burnaby Road, Portsmouth PO1 3FX, UK, Department of Physics & Astronomy, University of Utah, Salt Lake City, UT 84112, USA
  5. Institute of Cosmology, University of Portsmouth, Burnaby Road, Portsmouth PO1 3FX, UK, Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse 1, D-85748 Garching bei München, Germany
  6. Department of Astronomy, University of Winsconsin-Madison, 475 N. Charter Street, Madison, WI 53706-1582, USA, South African Astronomical Observatory, PO Box 9, Observatory 7935, Cape Town, South Africa, Department of Astronomy, University of Cape Town, Private Bag X3, Rondebosch 7701, South Africa
  7. McDonald Observatory, The University of Texas at Austin, 1 University Station, Austin, TX 78712, USA
  8. Apache Point Observatory and New Mexico State University, PO Box 59, Sunspot, NM 88349, USA, Sternberg Astronomical Institute, Moscow State University, Universitetskij pr. 13, Moscow, Russia
  9. Cavendish Laboratory, University of Cambridge, 19 J. J. Thomson Ave., Cambridge CB3 0HE, UK, Kavli Institute for Cosmology, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK
  10. Department of Physics and Astronomy, The University of Utah, 115 S. 1400 E., James Fletcher Bldg, Salt Lake City, UT 84112-0830, USA
  11. Center for Astrophysics and Space Astronomy, Department of Astrophysical and Planetary Sciences, University of Colorado, 389 UCB, Boulder, CO 80309-0389, USA
  12. Department of Physics and Astronomy, Vanderbilt University, VU Station B 1807, Nashville, TN 37235, USA
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1636229
Resource Type:
Published Article
Journal Name:
Monthly Notices of the Royal Astronomical Society
Additional Journal Information:
Journal Name: Monthly Notices of the Royal Astronomical Society Journal Volume: 496 Journal Issue: 3; Journal ID: ISSN 0035-8711
Publisher:
Oxford University Press
Country of Publication:
United Kingdom
Language:
English

Citation Formats

Maraston, C., Hill, L., Thomas, D., Yan, R., Chen, Y., Lian, J., Parikh, T., Neumann, J., Meneses-Goytia, S., Bershady, M., Drory, N., Bizyaev, D., Concas, A., Brownstein, J., Lazarz, D., Stringfellow, G., and Stassun, K. Stellar population models based on the SDSS-IV MaStar library of stellar spectra – I. Intermediate-age/old models. United Kingdom: N. p., 2020. Web. https://doi.org/10.1093/mnras/staa1489.
Maraston, C., Hill, L., Thomas, D., Yan, R., Chen, Y., Lian, J., Parikh, T., Neumann, J., Meneses-Goytia, S., Bershady, M., Drory, N., Bizyaev, D., Concas, A., Brownstein, J., Lazarz, D., Stringfellow, G., & Stassun, K. Stellar population models based on the SDSS-IV MaStar library of stellar spectra – I. Intermediate-age/old models. United Kingdom. https://doi.org/10.1093/mnras/staa1489
Maraston, C., Hill, L., Thomas, D., Yan, R., Chen, Y., Lian, J., Parikh, T., Neumann, J., Meneses-Goytia, S., Bershady, M., Drory, N., Bizyaev, D., Concas, A., Brownstein, J., Lazarz, D., Stringfellow, G., and Stassun, K. Tue . "Stellar population models based on the SDSS-IV MaStar library of stellar spectra – I. Intermediate-age/old models". United Kingdom. https://doi.org/10.1093/mnras/staa1489.
@article{osti_1636229,
title = {Stellar population models based on the SDSS-IV MaStar library of stellar spectra – I. Intermediate-age/old models},
author = {Maraston, C. and Hill, L. and Thomas, D. and Yan, R. and Chen, Y. and Lian, J. and Parikh, T. and Neumann, J. and Meneses-Goytia, S. and Bershady, M. and Drory, N. and Bizyaev, D. and Concas, A. and Brownstein, J. and Lazarz, D. and Stringfellow, G. and Stassun, K.},
abstractNote = {ABSTRACT We use the first release of the SDSS/MaStar stellar library comprising ∼9000, high S/N spectra, to calculate integrated spectra of stellar population models. The models extend over the wavelength range 0.36–1.03 µm and share the same spectral resolution ($R\sim 1800$) and flux calibration as the SDSS-IV/MaNGA galaxy data. The parameter space covered by the stellar spectra collected thus far allows the calculation of models with ages and chemical composition in the range $\rm {\mathit{ t}\gt 200 \,Myr, -2 \lt = [Z/H] \lt = + 0.35}$, which will be extended as MaStar proceeds. Notably, the models include spectra for dwarf main-sequence stars close to the core H-burning limit, as well as spectra for cold, metal-rich giants. Both stellar types are crucial for modelling λ > 0.7 µm absorption spectra. Moreover, a better parameter coverage at low metallicity allows the calculation of models as young as 500 Myr and the full account of the blue horizontal branch phase of old populations. We present models adopting two independent sets of stellar parameters (Teff, log g, [Z/H]). In a novel approach, their reliability is tested ‘on the fly’ using the stellar population models themselves. We perform tests with Milky Way and Magellanic Clouds globular clusters, finding that the new models recover their ages and metallicities remarkably well, with systematics as low as a few per cent for homogeneous calibration sets. We also fit a MaNGA galaxy spectrum, finding residuals of the order of a few per cent comparable to the state-of-art models, but now over a wider wavelength range.},
doi = {10.1093/mnras/staa1489},
journal = {Monthly Notices of the Royal Astronomical Society},
number = 3,
volume = 496,
place = {United Kingdom},
year = {2020},
month = {6}
}

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