[vsnet-alert 12467] OT J020804.2+373217: unusual object with ultrashort-period variations!

[Taichi Kato]

OT J020804.2+373217: unusual object with ultrashort-period variations!

   Terskol team (Maksim Andreev, relayed by E. Pavlenko) has reported
astonishing light curve of this object (=CSS101207:020804+373217, see
vsnet-alert 12464).

   The data indeed show large-amplitude (0.45 mag) variations, as inferred
from CRTS data.  Although the light curve generally resembles superhumps,
the period is very short (0.0193 d for the basic period).
The period would suggest an outburst of an ultracompact binary, particularly
AM CVn-type object, but the period might be too short for typical
dwarf nova-type helium CVs.  Spectroscopic observations are highly encouraged!

   The object might be an outbursting intermediate polar, although the
amplitudes of variations are rather too large and there was no strong
tendency of rapid fading, as is often seen in outbursting IPs.

   The third possibility is an IQ Eri-like outburst (cf. CBET 1633,
vsnet-alert 10853); another object resembling this is SDSS J140429.37+172359.4
(cf. vsnet-alert 11237, 11240).  The variation of OT J020804.2+373217,
however, looks more regular.

   In any case, further intensive observations are encouraged!