I will try to provide a resource page containing information on this source, in order to facilitate multi-frequency collaborations. If I ever find the time, this page is likely to be a shameless copy of Paul Ray's LS I +61 303 page.
The field of V635 CasCentral part of a 20-s white light exposure taken on 22nd August 1999 with the 1.52-m G. D. Cassini telescope at the Loiano Observatory, near Bologna, in Italy.
Moreover, the source is very variable and can brighten up by at least one magnitude in V. Colour changes are, however, not so spectacular, which is taken as indication of an optically thick envelope.
If anyone is interested in monitoring the source, they can use the local photometric sequence for calibration. This sequence was worked out by Iain Steele from the Astrophysics Research Institute at Liverpool John Moores University using the observations detailed in Negueruela et al. 1997, MNRAS 284, 859.
|B band sequence|
|V band sequence|
|R band sequence|
|I band sequence|
|Pulse Period||Ps = 3.6 s|
|Orbital Period||Po = 24.3 days|
|Eccentricity||e = 0.34|
|Proyected semimajor axis||axsini = 140.1 lt-s|
|Assumed Values (based on data)|
|Be star mass||MBe = 18 Msun|
|Be star radius||RBe = 8 Rsun|
|Neutron star mass||Mx = 1.4 Msun|
|Effective temperature||Teff = 26000 K|
|Derived Values (from data + asumptions)|
|Inclination angle||i = 43°|
|Semimajor axis||a = 6.6E10 m = 12 RBe|
|Periastron distance||rper = 8 RBe|