The rotation speed of the companion star in Aquila X-1.

Shahbaz, T.; Casares, J.; Charles, P. A.
Referencia bibliográfica

Astronomy and Astrophysics, v.326, p.L5-L8

Fecha de publicación:
10
1997
Número de autores
3
Número de autores del IAC
0
Número de citas
15
Número de citas referidas
15
Descripción
We have obtained medium resolution spectra of the neutron star X-ray transient Aql X-1 during quiescence. We determine the spectral type of the companion star to be K1 and also estimate its rotation speed to be 62^+30^_-20_km/s. By measuring the width of the Hα emission line profile of the accretion disc, we estimate the binary inclination to ~50° and also estimate the semi-amplitude of the companion star's radial velocity curve to be ~170km/s.