Retrieval of SDSS J1416+1348AB

TL;DR

This study analyzes the spectral energy distributions of the brown dwarf pair SDSS J1416+1348AB, using retrieval techniques to determine atmospheric properties and compare models, revealing insights into their composition, cloud structure, and formation history.

Contribution

First retrieval analysis of J1416A with a non-grey cloud model and second for J1416B, providing detailed atmospheric parameters and model comparisons for this brown dwarf pair.

Findings

J1416A is best fit by a non-grey cloud opacity model.

J1416B is best fit by a cloud-free model.

Most parameters are consistent within 1 sigma, with some exceptions.

Abstract

We present the distance-calibrated spectral energy distribution (SED) of the d/sdL7 SDSS J14162408+1348263A (J1416A) and an updated SED for SDSS J14162408+1348263B (J1416B). We also present the first retrieval analysis of J1416A using the Brewster retrieval code base and the second retrieval of J1416B. We find that the primary is best fit by a non-grey cloud opacity with a power-law wavelength dependence, but is indistinguishable between the type of cloud parameterization. J1416B is best fit by a cloud-free model, consistent with the results from Line et al. (2017). Most fundamental parameters derived via SEDs and retrievals are consistent within 1 sigma for both J1416A and J1416B. The exceptions include the radius of J1416A, where the retrieved radius is smaller than the evolutionary model-based radius from the SED for the deck cloud model, and the bolometric luminosity which is consistent within 2.5 sigma for both cloud models. The pair's metallicity and Carbon-to-Oxygen (C/O) ratio point towards formation and evolution as a system. By comparing the retrieved alkali abundances while using two opacity models, we are able to evaluate how the opacities behave for the L and T dwarf. Lastly, we find that relatively small changes in composition can drive major observable differences for lower temperature objects.