Colloq Abstract -Coppejans

Sep 29

11:00am Mountain

 

Deanne Coppejans (Northwestern)

 

Cataclysmic Variable Stars:  A new class of radio transient

 

Abstract

 

Cataclysmic Variable stars (CVs, binaries in which a white dwarf accretes matter from a main-sequence star via Roche-lobe overflow) were, until recently, believed not to be radio emitters. I will show that CVs are in fact a significant new class of galactic radio transient. The timing and sensitivity of earlier radio telescopes was simply not sufficient to detect these objects, but they will be detected in large numbers in upcoming radio surveys.

A number of radio emission mechanisms have been proposed for CVs. I will discuss these, and in particular focus on the discovery that CVs are likely launching jets - a finding that has far reaching implications for jet models in compact objects. Aside from the outstanding questions that CV radio studies can answer, it is also important that we learn to identify, classify and distinguish these objects from other classes of transient in future radio surveys.


 

 

 

 

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