jason-neal / nIR_paper

A paper derived from some of my phd work, rejected for publication mostly due to the lack of intersting results.

Towards the near-infrared detection of brown dwarf companions

Exploring methods to detect low mass stellar companions from blended spectra

Status:

• Rejected for publication
• I am not pursuing this work any further

Abstract

In this paper we attempt to detect the near-infrared (nIR) spectrum of candidate brown dwarf (BD) companions around FGK stars in order to assert or discard their stellar nature. First, Individual nIR spectra are fitted to a synthetic binary model comprised of two PHOENIX-ACES spectra using a $\chi^2$ approach. The observed spectra are wavelength calibrated and corrected for the atmospheric absorption with the aid of synthetic telluric models. This procedure was unable to successfully detect the spectra of the most massive companion in the sample. We explore how the companion recovery fitting performs on simulated observations and discuss reasons for the non-detection observed. From the injection-recovery analysis, this technique, in its current form, is insufficient to recover a companion below 3800K, corresponds to an upper mass limit of around (\rm 600M_{Jup}). A strong discrepancy between models and observations was found and is put forward as the main reason for the non-detection. This work highlights the challenges in the spectral detection of faint companions, and in particular the limitations of the companion detection with synthetic models at low companion/host flux ratios.