A Linearized Approach to Stellar Spectroscopy

by Dr. Sahar Shahaf

Weizmann Institute of Science

at Astrophysics and Cosmology Seminar

Wed, 13 Nov 2024, 11:10
Sacta-Rashi Building for Physics (54), room 207

Abstract

High-precision radial velocity measurements are crucial for exoplanet detection and characterization. Efforts to improve the precision have been made over the recent decades, with significant advancements in instrumentation, data reduction techniques, and statistical inference methods. However, despite these efforts, radial velocity precision exceeds the expected instrumental noise floor, mainly due to parasitic signals induced by stellar variability. This talk will propose a factorization method to overcome this limitation. This factorization is particularly suitable for controlling the effect of localized changes in the stellar emission profile, assuming some smooth function of a few astrophysical parameters governs them. The velocities are inferred using short-time Fourier transforms in a procedure equivalent to least-squares minimization in the wavelength domain. I will outline the method's potential, present the proof-of-concept tests conducted thus far, and discuss its underlying assumptions and challenges ahead.

Created on 09-11-2024 by Zitrin, Adi (zitrin)
Updaded on 09-11-2024 by Zitrin, Adi (zitrin)