[vsnet-alert 9548] Early superhumps in HS2331+3905

[Hiroyuki Maehara]

Dear colleagues,

G. Masi kindly sent us his excellent data on Sep. 5.
The data clearly show early superhumps with an amplitude of 0.4 mag.
We performed PDM and CLEAN period analysis to the data.
The best estimated early superhump period is 0.055840 +/- 0.000048
days (= 80.41 min) which is 0.8% shorter than the orbital period of 
81.08 min (Araujo-Betancor et al. 2005).

In addition to early superhumps, short period modulations (QPOs ?)
can be seen in the data. The period range of these modulations are 
0.0038 - 0.011 days.

Further time-resolved photometry and spectroscopy are strongly encouraged.

If you succeed in observing, please send your data to following address:
vsnet-campaign-report at ooruri.kusastro.kyoto-u.ac.jp

Best regards,
Hiroyuki Maehara
VSNET Collaboration Team