

Dear CBAers,

A new season, and wholesale changes in the CBA lineup.  The dwarf novae
have been running (fairly) quiet, and the various DQ Hers have been getting
pretty good coverage, thanks especially to George Roberts, Tut Campbell,
and David Boyd.  Berto has been taking advantage of that "severe clear"
streak of Pretorian winters - mainly on T Pyx - and Tom has been keeping
a steady watch on AM CVn.

Most of these stars are due for seasonal retirement.  T Pyx is gone for
the year (and, at first blush, never seemed to get its periodic signals
going while bright).  The year's coverage on AM CVn has been by far the
best ever, and the runs are getting too short.  The big cluster of DQ
Hers in the RA range 6-9 hr is retired until October.  GW Lib is still
available; but, based on Berto's extensive coverage this year, it just
doesn't look like this great performer of years past is doing much now.
So away with it too.  As many of you know, our GW Lib paper (Vican et al.
2011) is winding its way through referees.

Good targets for June-July coverage are:

(1) John Thorstensen's new CV at 17 06 09.68 +14 34 52.0.  In outburst
now, and therefore having a good chance of flashing a superhump period.
See his cba-chat message for a finding chart.

(2) V1494 Aql.  A 1999 nova remnant showing eclipses, and around 16th
magnitude.  At 1923+05, good for all hemispheres, and decently bright
around 16th magnitude.  Sure to be interesting.

(3) V1974 Cyg.  1992 nova remnant, sometimes "nova of the century"
(leaving that title nicely wide-open for the present century).  We have
a lot of archival data, showing positive and negative superhumps, but
no coverage for about 7 years.  I dunno quite how bright it is - but
if you can still get a time series, it's likely to be quite interesting.

(4) V630 Sgr. Similar story in the south (1936 nova). Of great interest,
but likely to be too faint (17.7??) for time series.  Can't blame me
for trying.

(5) V Sge, V617 Sgr.  Eclipsing "V Sge stars", with orbital period
changes likely to signify evolution (hallelujah!).  Light curves not
quite as photogenic as the superhumpers and DQ Hers - but
productive.

(6) V1432 Aql (RX1940-10).  One of our old-time favorites, with two
closely-spaced periods.  Now well placed for all hemispheres.  We haven't
touched it for a few years, and we're one season away from completion.
Fire up those telescopes.

(7) V1223 Sgr, AO Psc.  DQ Hers needing coverage.

(8) DQ Her.  The pulse ephemeris appears to be under control; but strangely,
for 2 nights in 2011, the pulse was 180 degrees out of phase!  Is this
real?  It's never been seen before in this star, or any star of this type.
For this reason, we *would* like to get more pulse timings this year.
You have to keep your cycle time below 20 s (to resolve the 71 s pulse).
But this could be an intriguing target - it definitely is for me.

(9) HP Lib. Still available and plenty bright at 13.4.  Good for
another month or so.

No implication of priority here.  Find something that looks interesting
to you... and then, of course, there's always the din of the dwarf
novae popping off.  Especially the new ones, which have been attracting
a lot of attention and furiously flashing superhumps.

Happy observing!

joe

