Publication detail

Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae. II: The Second Year (2009-2010)

Kato, T et al.

Original Title

Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae. II: The Second Year (2009-2010)

Type

journal article in Web of Science

Language

English

Original Abstract

Continued from Kato et al. (2009, PASJ, 61, S395), we collected the times of superhump maxima for 68 SU UMa-type dwarf novae, mainly observed during the 2009-2010 season. The newly obtained data confirmed the basic findings reported in Kato et al. (ibid.): the presence of stages A-C and the predominance of positive period derivatives during stage B in systems with superhump periods shorter than 0.07 d. There was a systematic difference in the period derivatives for the systems with superhump periods longer than 0.075 d between this study and Kato et al. (ibid.). We suggest that this difference was possibly caused by a relative lack of frequently outbursting SU UMa-type dwarf novae in this period regime in the present study. We recorded a strong beat phenomenon during the 2009 superoutburst of IY UMa. A close correlation between the beat period and the superhump period suggests that the changing angular velocity of the apsidal motion of the elliptical disk is responsible for the variation of the superhump periods. We also described three new WZ Sge-type objects with established early superhumps and one with likely early superhumps. We suggest that two systems, VX For and EL UMa, are WZ Sge-type dwarf novae with multiple rebrightenings. The O - C variation in OT J213806.6+261957 suggests that the frequent absence of rebrightenings in very short-P-orb objects can be the result of a sustained superoutburst plateau at the epoch when usual SU UMa-type dwarf novae return to quiescence, preceding a rebrightening. We also present a formulation for a variety of Bayesian extensions to traditional period analyses.

Keywords

accretion, accretion disks; stars: dwarf novae; stars: novae, cataclysmic variables

Authors

Kato, T; et al.

RIV year

2010

Released

25. 12. 2010

Publisher

C/O NATIONAL ASTRONOMICAL OBSERVATORY, 2-21-1 OSAWA, MITAKA-SHI, TOKYO, 181-8588, JAPAN

Location

Tokyo

ISBN

0004-6264

Periodical

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN

Year of study

62

Number

6

State

Japan

Pages from

1525

Pages to

1584

Pages count

60

BibTex

@article{BUT49888,
  author="Kato, T and et al.",
  title="Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae. II: The Second Year (2009-2010)",
  journal="PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN",
  year="2010",
  volume="62",
  number="6",
  pages="1525--1584",
  issn="0004-6264"
}