skip to main content

Title: The long-term light curve of the cataclysmic variable V794 Aquilae

The 1990-2012 light curve of the nova-like (NL) cataclysmic variable V794 Aql is studied in order to characterize and better understand the transitions to and from the faint state, and the variations within the bright state. Investigations of earlier portions of this data had concluded that the transitions to the low state were much slower than the rapid recovery, giving a sawtoothed appearance to the light curve. This behavior differs from that of most other VY Scl stars, which led to an interpretation of the large amplitude sawtooths as being due to an accretion disk (AD) instability. However, more recent photometry strongly suggests that the bright state itself has transitions of 1-1.5 mag, and that earlier studies had intermixed these bright state variations with the transitions to the low state. These newly recognized variations within the bright state sometimes appear as small outbursts (OBs) with typical amplitudes of 0.5-1.5 mag and spacings of ∼15-50 days. The rise times of the OBs are 2-3 times faster than the decline times. We argue that the V794 Aql bright state variations are due to AD behavior similar to that seen in dwarf novae, but with varying degrees of stability. Similar regular small OBsmore » have also been reported in other NL CVs, which we compare with V794 Aql. The true deep low states in V794 Aql appear to be normal, having transition speeds and shapes very similar to the transitions in other VY Scl stars.« less
Authors:
 [1] ;  [2] ;  [3]
  1. Astronomy Department, Indiana University, Swain Hall West, Bloomington, IN 47405 (United States)
  2. Department of Terrestrial Magnetism, Carnegie Inst. of Washington, 5241 Broad Branch Road NW, Washington, DC 20015 (United States)
  3. Arkansas Tech University, Department of Physical Sciences, 1701 N. Boulder, Russellville, AR 72801-2222 (United States)
Publication Date:
OSTI Identifier:
22340048
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astronomical Journal (New York, N.Y. Online); Journal Volume: 147; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCRETION DISKS; AMPLITUDES; COMPARATIVE EVALUATIONS; DIAGRAMS; NOVAE; PHOTOMETRY; PLASMA INSTABILITY; SAWTOOTH OSCILLATIONS; STABILITY; VELOCITY; VISIBLE RADIATION