Method of LSD profile asymmetry for estimating the center of mass velocities of pulsating stars
Date Issued
2016
Author(s)
Abstract
We present radial velocity analysis for 20 solar neighborhood RR Lyrae and 3 Population II Cepheids. High-resolution spectra were observed with either TNG/SARG or VLT/UVES over varying phases. To estimate the center of mass (barycentric) velocities of the program stars, we utilized two independent methods. First, the 'classic' method was employed, which is based on RR Lyrae radial velocity curve templates. Second, we provide the new method that used absorption line profile asymmetry to determine both the pulsation and the barycentric velocities even with a low number of high-resolution spectra and in cases where the phase of the observations is uncertain. This new method is based on a least squares deconvolution (LSD) of the line profiles in order to an- alyze line asymmetry that occurs in the spectra of pulsating stars. By applying this method to our sample stars we attain accurate measurements (+- 2 kms^-1) of the pulsation component of the radial velocity. This results in determination of the barycentric velocity to within 5 kms^-1 even with a low number of high- resolution spectra. A detailed investigation of LSD profile asymmetry shows the variable nature of the project factor at different pulsation phases, which should be taken into account in the detailed spectroscopic analysis of pulsating stars.
Coverage
RRL2015: High-Precision Studies of RR Lyrae Stars
All editors
Szabados, L.; Szabó, R.; Kinemuchi, K.
Volume
105
Start page
105
Conferenece
RRL2015: High-Precision Studies of RR Lyrae Stars
Conferenece place
Visegràd (Ungheria)
Conferenece date
19-22 Ottobre, 2015
Issn Identifier
0238-2091
Ads BibCode
2016CoKon.105..105B
Rights
open.access
File(s)![Thumbnail Image]()
Loading...
Name
Britavsky.pdf
Description
PDF editoriale
Size
242.45 KB
Format
Adobe PDF
Checksum (MD5)
586241ba19e7f193d75d6a5e701f8561