Aquila X-1: A Low-Inclination Soft X-Ray Transient

Authors

T. Shahbaz, University of Oxford
J. R. Thorstensen, Dartmouth College
P. A. Charles, University of OxfordFollow
N. D. Sherman, Dartmouth College

Document Type

Article

Publication Date

6-1-1998

Publication Title

Monthly Notices of the Royal Astronomical Society

Department

Department of Physics and Astronomy

Abstract

We have obtained I-band photometry of the neutron star X-ray transient Aql X-1 during quiescence. We find a periodicity at 2.487 cycles d⁻¹, which we interpret as twice the orbital frequency (19.30±0.05 h). Folding the data on the orbital period, we model the light-curve variations as the ellipsoidal modulation of the secondary star. We determine the binary inclination to be 20°–30° (90 per cent confidence) and also determine the 95 per cent upper limits to the radial velocity semi-amplitude and rotational broadening of the secondary star to be 117 and 50 km s⁻¹, respectively.

DOI

10.1046/j.1365-8711.1998.01474.x

Dartmouth Digital Commons Citation

Shahbaz, T.; Thorstensen, J. R.; Charles, P. A.; and Sherman, N. D., "Aquila X-1: A Low-Inclination Soft X-Ray Transient" (1998). Dartmouth Scholarship. 1877.
https://digitalcommons.dartmouth.edu/facoa/1877