The Sonora Substellar Atmosphere Models VI. Red Diamondback: Extending Diamondback with SPHINX for Brown Dwarf Early Evolution

OVERVIEW V2 UPDATE: The evolution code's atmospheric boundary condition now has a "weighted transition region" across Teff 2000 - 2400 K (where both the original Sonora Diamondback and new SPHINX grids have modeled atmospheres). This differs from V1, where the atmospheric boundary condition used Sonora Diamondback atmospheres at Teff < 2400 K, and SPHINX atmospheres at Teff >= 2400 K. The V2 atmospheric boundary condition and the regions where one or both of the atmosphere grids are used can be seen in Fig. 2 of the arXiv pre-print, and are described further in Section 2.2.-----Presented here are models for non-irradiated, substellar mass objects spanning ages from 1 Myr to 15 Gyr, which belong to the Sonora model series. The models are described in Davis et al. accepted. The files inlcuded here are thermal evolution tracks ("evolution") and synthetic photometry ("photometry").This particular set of evolution tracks and photometry, which we name Sonora "Red Diamondback", supersedes the original Sonora Diamondback (Morley et al. 2024) evolution tracks due to the inclusion of high Teff atmospheric boundary conditions from the SPHINX M dwarf Spectral Grid. This addition to the atmospheric boundary condition allows for an accurate treatment of evolution at early ages. The evolution models presented here are computed for objects with 3.0 ≤ log g (cgs) ≤ 5.5 and 900 ≤ Teff ≤ 4000K (steps in Teff are 100 K and steps in log g are 0.25.) Models are provided for [M/H] = -0.5, 0.0, and +0.5 and "rainout" chemical equilibrium. For the convenience of having a rectangular table in (Teff, gravity) space, the atmospheric models used as boundary conditions in the evolution models presented here were calculated in regimes that are not reached by the evolution, such as very high gravity and very low Teff. Refer to the evolution tables to identify combinations of Teff and log g outside the bounds covered by the evolution. For other Sonora models that cover different temperature, gravities, metallicities, and disequilibrium chemistry, see Sonora Bobcat, Sonora Cholla, and Sonora Elf Owl. EVOLUTIONEvolution tables include each of the three metallicities (+0.5, +0.0, -0.5) and span ages from 1 Myr to 15 Gyr for objects greater than the hydrogen burning minimum mass down to half a Jupiter mass.PHOTOMETRYWe include tables of absolute magnitudes in a number of photometric systems commonly used in brown dwarf and exoplanet research (MKO, WISE, Spitzer IRAC, etc).  Magnitudes are computed on the Vega system. CREDITSIf you use these tables in your research, please cite Davis et al. submitted. ([LINK HERE])