Galactic Be star inclination angles Virtual Observatory Resource

Authors
  1. Sigut T.A.A.
  2. Ghafourian N.R.
  3. Published by
    CDS
Abstract

Using a sample of 92 Galactic Be stars, we compare inclination angles (the angle between a star's rotation axis and the line of sight) determined from H{alpha} emission-line profile fitting to those determined by the spectroscopic signature of gravitational darkening. We find good agreement: 70% of the sample (64 out of 92 stars) is consistent with zero difference between the two methods using 1{sigma} errors, and there is a strong linear correlation coefficient between the two methods of r=+0.63+/-0.05. There is some evidence that the H{alpha} profile fitting method overestimates the inclination angle for i<~25{deg}, perhaps due to the neglect of incoherent electron scattering on the H{alpha} line widths, while the gravitational darkening method underestimates the inclination angle for i>~70{deg}, perhaps due to the neglect of disk radiative transfer effects on the optical spectrum. Overall, it is demonstrated that a single H{alpha} spectrum of modest resolution and SNR can be used to extract a useful estimate for the inclination angle of an individual Be star. This allows equatorial rotation velocities for individual Be stars to be derived from vsini measurements and will allow Be stars to be used to search for correlated spin axes in young, open clusters if unbiased (with respect to inclination) samples of Be stars are used.

Keywords
  1. be-stars
  2. stellar-spectral-types
  3. visible-astronomy
  4. h-alpha-photometry
  5. spectroscopy
Bibliographic source Bibcode
2023ApJ...948...34S
See also HTML
https://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/948/34
IVOA Identifier IVOID
ivo://CDS.VizieR/J/ApJ/948/34
Document Object Identifer DOI
doi:10.26093/cds/vizier.19480034

Access

Web browser access HTML
https://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/948/34
https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/948/34
http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/948/34
IVOA Table Access TAP
https://tapvizier.cds.unistra.fr/TAPVizieR/tap
Run SQL-like queries with TAP-enabled clients (e.g., TOPCAT).
IVOA Cone Search SCS
For use with a cone search client (e.g., TOPCAT).
https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/948/34/table1?
https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/948/34/table1?
http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/948/34/table1?

History

2025-07-17T08:11:22Z
Resource record created
2025-07-17T08:11:22Z
Created
2025-08-01T20:11:25Z
Updated

Contact

Name
CDS support team
Postal Address
CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France
E-Mail
cds-question@unistra.fr