There is a newer version of this record available.

Poster Open Access

Determination of Fundamental Properties of M-dwarfs from New Model Atmospheres and Spectra

Iyer, Aishwarya; Line, Michael; Muirhead, Philip; Fortney, Jonathan; Gharib-Nezhad, Ehsan


About 70% of stars in the Milky Way galaxy are M-dwarfs. They span a range of low masses (0.08 - 0.6 solar mass), have faint luminosities (less than 0.05 solar luminosity), and temperatures ranging between 2500 K - 4000 K, facilitating molecule formation throughout their atmospheres. Standard stellar analysis methods to accurately characterize them have thus far proved challenging—in not correctly accounting for vast variations in their atmospheric structures. Our modeling framework will determine fundamental atmospheric properties of M-dwarfs with a two-pronged approach: a physically motivated self-consistent radiative-convective model grid with up-to-date opacities, constrained by thermo-chemical and hydrostatic equilibrium, radiative and convective transport as well as a data-driven Bayesian retrieval technique. We leverage the broadband molecular absorption features occurring in low-resolution M-dwarf spectra (from SpeX Prism Library) and use them to our advantage in acquiring robust constraints on the effective temperature, surface gravity and bulk chemical properties of M-dwarf atmospheres. Our approach lies in the interface between the standard self-consistent prescription for modeling stellar atmospheres and an assumption-free data-driven retrieval method, where new physical intuition can be obtained about our understanding of low-mass stars.

Files (2.1 MB)
Name Size
2.1 MB Download
  • John J. Bochanski et al 2010 AJ 139 2679, doi:10.1088/0004-6256/139/6/2679

  • Gregory Laughlin et al 1997 ApJ 482 420, doi:10.1086/304125

  • Mark J. Veyette et al 2016 ApJ 828 95, doi:10.3847/0004-637X/828/2/95

  • Gharib-Nezhad, E., Iyer, A., et al. (submitted to ApJ, 2021)

  • T.-O. Husser et al., 2013 A&A 553 A6, doi: 10.1051/0004-6361/201219058

  • Buchner et al. 2016, ASCL, ascl-1606:005

  • Adam Burgasser 2014, arXiv:1406.4887

  • Ralph Schönrich, et al. 2019, MNRAS. 487.3: 3568-3580., doi: 10.1093/mnras/stz1451

  • Ian Czekala et al 2015 ApJ 812 128, doi:10.1088/0004-637X/812/2/128/meta

  • Mann et al. 2013, AJ, 145, 2, 52:15pp, doi: 10.1088/0004-6256/145/2/52

  • Mann et al. 2014, AJ, 147, 6, 160:11pp, doi:10.1088/0004-6256/147/6/160

All versions This version
Views 14556
Downloads 12753
Data volume 261.4 MB109.0 MB
Unique views 11749
Unique downloads 10846


Cite as