CSS 121005:212625+201948 campaign update‏‏‏ – Sept 22

Forums Variable Stars Campaign on a possible ER UMa Dwarf Nova from the Catalina Real Time Sky Survey‏ CSS 121005:212625+201948 campaign update‏‏‏ – Sept 22

Jeremy Shears

It’s time for an update on this target – a little overdue as I have been on hols for the last couple of weeks.

In the previous update I reported that at the end of August we had a short outburst. During the first week of September the star was in quiescence. Then a long outburst started on 7 September, lasting at least 12 days. Ian Miller valiantly carried out time-series photometry on several nights during the outburst. This again revealed hump-like features, with a period near 0.0807d, although there was a significant alternative around 0.0881d. Observations during the previous long outburst, in July, suggested a period near 0.0882d, with a significant alternative around 0.0810d. In each case the runs were rather short, introducing the uncertainty in the period. The upshot of all this is that further observations are needed!

So far we have observed long (>10 day) outbursts in late April/early May, early July and mid September, which might point to a ~2 month supercycle. Will we see the next one in early November? Of course there are short (~3 day) between the long outburst that we need to track too.

Many thanks to everyone who has contributed to the campaign so far.

Go well!