EDP Sciences
Free Access
Volume 369, Number 1, April I 2001
Page(s) 108 - 116
Section Formation, structure and evolution of stars
DOI https://doi.org/10.1051/0004-6361:20010146

A&A 369, 108-116 (2001)
DOI: 10.1051/0004-6361:20010146

The Be/X-ray transient 4U 0115+63/V635 Cassiopeiae

I. A consistent model
I. Negueruela1, 2 and A. T. Okazaki3

1  SAX SDC, ASI, c/o Nuova Telespazio, via Corcolle 19, 00131 Rome, Italy
2  Astrophysics Research Institute, Liverpool John Moores University, Byrom St., Liverpool L3 3AF, UK
3  Faculty of Engineering, Hokkai-Gakuen University, Toyohira-ku, Sapporo 062-8605, Japan

(Received 22 July 1999 / Accepted 10 January 2001 )

We present photometry and high SNR spectroscopy in the classification region of V635 Cas, the optical counterpart to the transient X-ray pulsar 4U 0115+63, taken at a time when the circumstellar envelope had disappeared. V635 Cas is classified as a B0.2Ve star at a distance of 7-8 kpc. We use the physical parameters derived from these observations and the orbit derived from X-ray observations to elaborate a model of the system based on the theory of decretion discs around Be stars. We show that the disc surrounding the Be star is truncated by the tidal/resonant interaction with the neutron star and cannot be in a steady state. This explains many of the observed properties of 4U 0115+63. In particular, because of this effect, under normal circumstances the neutron star cannot accrete from the disc, which explains the lack of regular type I outbursts from the source.

Key words: stars: circumstellar matter -- stars: emission-line, Be -- stars: individual: 4U 0115+63, -- binaries: close -- stars: neutron -- X-ray: stars

Offprint request: I. Negueruela, ignacio@astro.u-strasbg.fr

SIMBAD Objects

© ESO 2001

Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.