Alert Notice 378: Request to monitor RE J1255+266 for HST Observations

May 5, 2008: Dr. Paula Szkody (University of Washington) and collaborators have requested our help in monitoring the cataclysmic variable RE J1255+266 for upcoming Hubble Space Telescope observations. Dr. Szkody requests nightly monitoring of this source beginning immediately, and continuing through 2008 May 15 UT.

RE J1255+266 is located at RA 12:55:10.80, Dec +26:42:27.0 (J2000)

This star is a cataclysmic variable not previously seen in outburst, and is being observed as part of a larger study of pulsating white dwarf primaries in cataclysmic variables. In particular, Szkody and collaborators are investigating the effects that higher temperatures and larger rotation velocities caused by accretion have on the pulsation behavior.

This object is extremely faint at quiescence, with V<19.0. AAVSO observations are requested to ensure that the object remains in quiescence when observed with HST, as it could damage the instrument if it were to go into outburst. AAVSO observations will be used to make a "go"/"no go" decision prior to the opening of the HST observing window, and will also be used in the analysis of the resulting data. Observations are requested to continue through at least the end of the science observing window on 2008 May 14 09:30 UT.

Observers are asked to monitor RE J1255+266 beginning immediately (2008 May 05 UT). Visual observers please observe as normal, and report any "fainter than" estimates using the faintest comparison star magnitude you can reach. CCD observers are asked to use filters during observations if available; V filter is preferred, but B,Rc, and Ic may also be used. Detection of the variable itself is not required; please use sufficient exposure time to detect at least the V=16.998 comparison star (RA 12:54:57.12, Dec +26:41:33.6, J2000) with a S/N of 10, and report the observation as a "fainter-than" measure.  Please go as faint as possible in reasonable time, preferably to the faintest comparison star as you can.

Please submit all data to the AAVSO via WebObs as promptly as possible. In the event of an outburst, please contact the AAVSO immediately. 

Please submit data to the AAVSO using the name "RE J1255+266" or the AUID "000-BCY-206".

Charts for RE J1255+266 are available at this URL:

For more information on this campaign, visit the following URL:

This campaign is being organized at AAVSO HQ by Dr. Matthew Templeton.



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