Hi CBAers,The AM CVn project is nearing completion, and I wrote up a preliminary version for the SAS conference (attached). Their format requirements caused the footnotes to be mangled/skipped, but I'll replace this with a regular-journal article in a few weeks. AM CVn remains a good target, but should now take a back seat to HP Lib - which is the only other always-bright AM CVn star in the sky.
The message on HP Lib is simple - all night, every night. Southerners should keep the airmass under 2.0; northerners can go a little further (maybe 2.2 or 2.3) on a really good night. (Sometimes "hours away from meridian" is a more reliable demerit than simple airmass,)
There are great never-mined treasures in HP Lib. To my amazement, no one has published a time-series study since ours from 15 years ago. We can vastly improve on that now, having acquired a world-wide spread for near-equatorial stars.
CR Boo is a close competitor. Because it wanders somewhat in mean magnitude (generally 14-15.5), the analysis is trickier (and debatable). But it too is very well placed in the sky, by virtue of season and near-equatorial status.
That's the helium-star report. I'll write re other projects, esp. Maxie and the old novae, in a few days.
joe
Attachment:
amcvn-sas2019.pdf
Description: Adobe PDF document
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