Difference between revisions of "Triggers:CVs"

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== VY Sculptoris ==
 
== VY Sculptoris ==
 
A subclass of cataclysmic variables exhibiting occasional drops by several magnitudes at irregular intervals. The prototype of the class had shown a deep low-state in 2008, first since 1983 ([http://uk.arxiv.org/abs/0910.0475 Greiner et al. 2009]).
 
A subclass of cataclysmic variables exhibiting occasional drops by several magnitudes at irregular intervals. The prototype of the class had shown a deep low-state in 2008, first since 1983 ([http://uk.arxiv.org/abs/0910.0475 Greiner et al. 2009]).
It is suspected these are supersoft X-ray binaries, containing a WD.
 
  
 
[[File:CV-VYScl.png|300px|right]]
 
[[File:CV-VYScl.png|300px|right]]
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* mechanism not well understood
 
* mechanism not well understood
 
* some of VY Scl stars are supersoft X-ray sources during optical low-states.
 
* some of VY Scl stars are supersoft X-ray sources during optical low-states.
 +
* V504 Cen has period of 4.21h

Revision as of 10:05, 6 October 2009

There is a very large variety of behaviours of CVs.

VY Sculptoris

A subclass of cataclysmic variables exhibiting occasional drops by several magnitudes at irregular intervals. The prototype of the class had shown a deep low-state in 2008, first since 1983 (Greiner et al. 2009).

CV-VYScl.png
  • amplitude: several magnitudes
  • drop time scale: 10-30 days
  • low state lasts for about 100 days
  • some periodicity (P about 10 days) is present
  • mechanism not well understood
  • some of VY Scl stars are supersoft X-ray sources during optical low-states.
  • V504 Cen has period of 4.21h