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Title: Direct Method to Compute Doppler Beaming Factors in Binary Stars
Abstract The Doppler beaming effect, induced by the reflex motion of stars, introduces flux modulations and serves as an efficient method to photometrically determine mass functions for a large number of close binary systems, particularly those involving compact objects. In order to convert observed beaming-flux variations into a radial-velocity curve, precise determination of the beaming factor is essential. Previously, this factor was calculated as a constant, assuming a power-law profile for stellar spectra. In this study, we present a novel approach to directly compute this factor. Our new method not only simplifies the computation, especially for blue bands and cool stars, but also enables us to evaluate whether the relationship between beaming flux and radial velocity can be accurately described as linear. We develop a Python code and compute a comprehensive beaming-factor table for commonly used filter systems covering main-sequence, subgiant, and giant stars, as well as hot subdwarf and white dwarf stars. Both the code and our table are archived and publicly available on Zenodo: doi:10.5281/zenodo.13049419.  more » « less
Award ID(s):
1927130
PAR ID:
10649205
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
IOP
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
972
Issue:
2
ISSN:
0004-637X
Page Range / eLocation ID:
151
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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