[vsnet-campaign-dn 11196] ASASSN-14cc

[Taichi Kato]

ASASSN-14cc

   Let's continue observations in the next season, too.

http://arxiv.org/abs/1501.06659

Title: ASASSN-14cc: Likely Helium Analog of RZ Leonis Minoris
Authors: Taichi Kato (Kyoto U), Franz-Josef Hambsch (GEOS, BAV, Vereniging Voor
  Sterrenkunde), Berto Monard (Center for Backyard Astronomy Kleinkaroo)
Categories: astro-ph.SR
Comments: 5 pages, 5 figures, accepted for publication in PASJ (Letters)
License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
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  We identified that ASASSN-14cc is a very active dwarf nova spending
approximately 60% of the time in outburst. Our long-term photometry revealed
that the object shows long outbursts recurring with a period of 21-33 d and
very brief short outbursts lasting less than 1 d. The maximum decline rate
exceeds 2.8 mag/d. The duration of long outbursts is 9-18 d, comprising 50-60%
of the recurrence time of long outbursts. We detected 0.01560-0.01562 d (22.5
min) modulations during long outbursts, which we identified to be superhumps.
These features indicate that ASASSN-14cc has outburst parameters very similar
to the extreme dwarf nova RZ LMi but with a much shorter superhump period. All
the observations can be naturally understood considering that this object is a
helium analog (AM CVn-type object) of RZ LMi. The highest outburst activity
among AM CVn-type objects can be understood as the high-mass transfer rate
expected for the orbital period giving a condition close to the stability limit
of the accretion disk. In contrast to RZ LMi, this object shows little evidence
for premature quenching of the superoutburst, which has been proposed to
explain the unusual outburst parameters in RZ LMi.