The Payne: Self-consistent ab initio Fitting of Stellar Spectra

Date

2019

Authors

Ting, Yuan-Sen
Conroy, Charlie
Rix, Hans-Walter
Cargile, Phillip A

Journal Title

Journal ISSN

Volume Title

Publisher

IOP Publishing

Abstract

We present The Payne, a general method for the precise and simultaneous determination of numerous stellar labels from observed spectra, based on fitting physical spectral models. The Payne combines a number of important methodological aspects: it exploits the information from much of the available spectral range; it fits all labels (stellar parameters and elemental abundances) simultaneously; it uses spectral models, where the structure of the atmosphere and the radiative transport are consistently calculated to reflect the stellar labels. At its core The Payne has an approach to accurate and precise interpolation and prediction of the spectrum in high-dimensional label space that is flexible and robust, yet based on only a moderate number of ab initio models ( for 25 labels). With a simple neural-net-like functional form and a suitable choice of training labels, this interpolation yields a spectral flux prediction good to 10-3 rms across a wide range of T eff and (including dwarfs and giants). We illustrate the power of this approach by applying it to the APOGEE DR14 data set, drawing on Kurucz models with recently improved line lists: without recalibration, we obtain physically sensible stellar parameters as well as 15 elemental abundances that appear to be more precise than the published APOGEE DR14 values. In short, The Payne is an approach that for the first time combines all these key ingredients, necessary for progress toward optimal modeling of survey spectra; and it leads to both precise and accurate estimates of stellar labels, based on physical models and without "recalibration." Both the codes and catalog are made publicly available online.

Description

Keywords

methods, data analysis – stars, abundances – techniques, spectroscopic Supporting material, machine-readable table

Citation

Source

The Astrophysical Journal

Type

Journal article

Book Title

Entity type

Access Statement

Open Access

License Rights

Restricted until

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