Alert Notice 428: Monitoring requested of the peculiar cataclysmic variable FS Aurigae

November 30, 2010: Dr. Vitaly Neustroev (U. of Oulu, Finland) requests continuous, nightly monitoring of the cataclysmic variable FS Aurigae during the current (2010-2011) observing season to clearly define the start and end times of several consecutive dwarf nova outbursts and measure their outburst properties.  FS Aurigae is a peculiar dwarf nova system exhibiting a number of periodicities and other phenomena whose origin is not yet understood.  In addition to the strange periodicities present, the star also exhibits very short dwarf nova outbursts that have not been well-defined and covered fully throughout the cycle.  The purpose of this campaign is to detect the next outburst of FS Aurigae as early as possible, and then to follow the outburst throughout its duration with intensive time-series observations.  This will then be continued throughout the coming observing season.

Dr. Neustroev requests that observations be made at least twice on every clear night, and that all observations -- both positive detections and negative "fainter-than" measurements -- be reported as quickly as possible via the AAVSO's WebObs data submission tool.  It is critically important to detect and report the onset of the next outburst within a few hours; a number of observers spaced relatively evenly in longitude can accomplish this by adding this star to their nightly monitoring program, so intensive time-series observations are *not* required for the monitoring phase.

Upon detection and announcement of the outburst, observers are then encouraged to actively follow this star, and instrumental observers capable of conducting time-series photometry are encouraged to do so. Any filter (including clear) is acceptable for time-series, but V-filter observations are encouraged if possible.  FS Aur typically varies between V=16 and 17 in quiescence, and outbursts typically reach V=13.5-14.0.  For nightly monitoring, photometric errors of 0.1-0.2 magnitude are acceptable, but observers capable of attaining better signal to noise in under 5-10 minutes are encouraged to do so.  For observers making time-series measurements during outburst, please attempt to reach errors better than 0.05 magnitude, preferably below 0.02.  For observers making fainter-than estimates at all stages of the project, any observations that establish the star as fainter than V=14.5-15.0 are most useful.  Instrumental observers are also asked to ensure that their computers are synchronized with a UTC time standard, so that time-series data from multiple observers may be correctly combined.

FS Aurigae is located at the following (J2000) coordinates:

    RA: 05 47 48.32 , Dec: +28 35 11.6

Charts for FS Aurigae may be generated using AAVSO VSP:

Please promptly submit all observations to the AAVSO using the name "FS AUR". This campaign is referenced on the AAVSO Observing Campaigns page.

This Alert Notice was prepared by Matthew R. Templeton.

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