PRECISE ROTATION RATES FOR FIVE SLOWLY ROTATING A STARS

Projected rotation rates of five early A-type slowly rotating stars are measured spectroscopically to a precision of 0.2 km s super(-1). A detailed Fourier analysis is done, as well as a comparison of profiles directly. Macroturbulence is needed in addition to rotation to reproduce the profile shape...

Full description

Saved in:
Bibliographic Details
Published in:The Astronomical journal 2014-04, Vol.147 (4), p.1-13
Main Author: Gray, David F
Format: Article
Language:English
Subjects:
A stars
ACCURACY
ASTROPHYSICS, COSMOLOGY AND ASTRONOMY
ATMOSPHERES
COMPARATIVE EVALUATIONS
DISPERSIONS
FOURIER ANALYSIS
Rotating
ROTATION
Sidelobes
SPECTROSCOPY
STARS
Transforms
TURBULENCE
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Projected rotation rates of five early A-type slowly rotating stars are measured spectroscopically to a precision of 0.2 km s super(-1). A detailed Fourier analysis is done, as well as a comparison of profiles directly. Macroturbulence is needed in addition to rotation to reproduce the profile shapes. An upper limit of [lap]2 kms super(-1) is placed on the microturbulence dispersion. Small unexplained differences between the models and the observations are seen in the sidelobe structure of the transforms. The v sin i results are: alpha Dra, 26.2; [theta] Leo, 22.5; alpha CMa A, 16.7; gamma Gem A, 10.7; o Peg, 6.0 km s super(-1). These stars are suitable as standards for measuring rotation using less fundamental methods.
ISSN:0004-6256
1538-3881
1538-3881
DOI:10.1088/0004-6256/147/4/81