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

Bibcode
1997A&A...326L...5S
Shahbaz, T.; Casares, J.; Charles, P. A.
Bibliographical reference

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

Advertised on:
10
1997
Journal
Astronomy and Astrophysics
Number of authors
3
IAC number of authors
0
Citations
15
Refereed citations
15
Description
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.
Type
Refereed

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