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Title: The Sonora Brown Dwarf Atmosphere and Evolution Models. I. Model Description and Application to Cloudless Atmospheres in Rainout Chemical Equilibrium

Journal Article · · The Astrophysical Journal
ORCiD logo [1]; ORCiD logo [2];  [3]; ORCiD logo [4]; ORCiD logo [5]; ORCiD logo [6]; ORCiD logo [7];  [8]; ORCiD logo [9]; ORCiD logo [10]; ORCiD logo [11]
  1. Univ. of Arizona, Tucson, AZ (United States)
  2. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  3. Dordt University, Boulder, CO (United States)
  4. NASA Ames Research Center (ARC), Moffett Field, Mountain View, CA (United States)
  5. SETI Institute, Mountain View, CA (United States)
  6. Univ. of Texas, Austin, TX (United States)
  7. Univ. of California, Santa Cruz, CA (United States)
  8. Univ. of California, Santa Cruz, CA (United States); Leiden Observatory (Netherlands)
  9. Univ. of California, Santa Cruz, CA (United States); New Mexico State Univ., Las Cruces, NM (United States)
  10. Univ. of California, Santa Cruz, CA (United States); Univ. of Maryland, College Park, MD (United States)
  11. Univ. of California, Santa Cruz, CA (United States); Univ. of Leicester (United Kingdom)

Here we present a new generation of substellar atmosphere and evolution models, appropriate for application to studies of L-, T-, and Y-type brown dwarfs and self-luminous extrasolar planets. The models describe the expected temperature-pressure profiles and emergent spectra of atmospheres in radiative-convective equilibrium with effective temperatures and gravities within the ranges 200 ≤ Teff ≤ 2400 K and $$2.5\leqslant \mathrm{log}g\leqslant 5.5$$. These ranges encompass masses from about 0.5 to 85 Jupiter masses for a set of metallicities ([M/H] = – 0.5 to + 0.5), C/O ratios (from 0.5 to 1.5 times that of solar), and ages. These models expand the diversity of model atmospheres currently available, notably to cooler effective temperatures and greater ranges in C/O. Notable improvements from past such models include updated opacities and atmospheric chemistry. Here we describe our modeling approach and present our initial tranche of models for cloudless, chemical equilibrium atmospheres. We compare the modeled spectra, photometry, and evolution to various data sets.

Research Organization:
Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
Sponsoring Organization:
USDOE; National Aeronautics and Space Administration (NASA)
Grant/Contract Number:
89233218CNA000001
OSTI ID:
1865001
Report Number(s):
LA-UR-21-22300; TRN: US2305811
Journal Information:
The Astrophysical Journal, Vol. 920, Issue 2; ISSN 0004-637X
Publisher:
IOP PublishingCopyright Statement
Country of Publication:
United States
Language:
English

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Figures / Tables (18)