(cba:news) HST coverage

[Joe Patterson]

Dear CBAers,

Now for something different.  We hope and expect to get some HST spectra 
this fall, and beyond.  But the CVs need to be in quiescence for the 
observations to proceed, because they're worried that the strong UV flux 
in outburst will fry the detectors.  We need to essentially prove that 
the stars will be in quiescence - and in particular that they have been 
in quiescence for at least a month.

To do this, we'd like nightly observations of each star. In the next 
message, I'll forward Boris Gansicke's description of the full list, 
which has references, links, etc.  Here I just want to mention the stars 
for which we need to observations NOW.  This is not a CBA-style 
campaign, calling for time series. Snapshot observations are fine. 
V-band magnitudes are ideal, but unfiltered is OK too, if you know how 
bright the comparison star is.  Upper limits are fine too; they'll 
likely attest to quiescence, but they need to be quantitative.  Here's 
the list:

SDSS 0137-09 = GZ Cet
HM Leo = NSV 18241
SDSS 1006+2337 = CSS 050301:100658+233724
MR UMa = RX1131+43
SDSS 1538+5123 (also RX)
BB Ari
SDSS 0407-0644 = LT Eri

Actually, the last of these *is* a good CBA target, and in October will 
be a superb target - beautiful eclipses and superhumps.  For now we'll 
settle for snapshots, though time series would be nice.

There are three other stars which will very soon get on our list, so I 
might as well list 'em now:

HS 0218+3229
SDSS 0011-0647
RX 023238.8-371812

These are plenty useful now.  I earnestly hope that some of you guys can 
launch an observing program like this!  Different from our usual, and 
with more overhead with all the target-shifting... but it's the key to 
getting the HST go-ahead, which will give us our long-sought glimpse of 
the ultraviolet spectra.

joe