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[vsnet-campaign-news 134] Possible outburst of GK Per (Nova 1901)
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Possible Outburst of GK Per
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GK Per, the bright nova in 1901, seems to be undergoing one of its
"dwarf nova-type" minor outbursts. These outbursts occur infrequently
(once in 1000 d), and can reach mag 10-11. The last outburst of GK Per
was observed in 1999 February, which was predicted by Tsutomu Watanabe
(VSOLJ, Japan) less than a month before the outburst rise. The white
dwarf in GK Per has a spin period of 351 s, and short-pewriod variations
at similar periods were observed during the past outbursts. Furthermore,
photometric quasi-periodic modulations of unknown nature with periods
of several tens of minites to hours have been also observed.
Follow-up time-resolved observations of the present possible outburst
is strongly encouraged.
YYYYMMDD(UT) mag observer
20020202.179 132 (Mike Simonsen)
20020202.812 128 (Pavol A. Dubovsky)
20020202.814 131 (Eddy Muyllaert)
20020202.822 131 (Georg Comello)
20020202.846 131 (Alfons Diepvens)
20020202.856 131 (Wolfgang Kriebel)
20020202.943 131 (Maciej Reszelski)
20020203.119 132 (Robert J. Modic)
20020203.778 128 (Pavol A. Dubovsky)
20020203.822 131 (Maciej Reszelski)
20020203.928 129 (Eddy Muyllaert)
20020204.060 129 (Erwin van Ballegoij)
20020204.760 128 (Pavol A. Dubovsky)
20020204.917 132 (Maciej Reszelski)
20020205.105 132 (Mike Simonsen)
20020205.758 130 (Pavol A. Dubovsky)
20020205.833 130 (Eddy Muyllaert)
20020205.837 130 (Georg Comello)
20020205.962 130 (Hazel McGee)
20020206.549 132 (Masashi Nakatani)
20020206.874 132 (Gary Poyner)
20020206.900 128 (Hazel McGee)
20020207.035 129 (Erwin van Ballegoij)
20020207.117 131 (Mike Simonsen)
20020208.017 129 (Erwin van Ballegoij)
20020208.101 129 (Mike Simonsen)
20020208.851 131 (Eddy Muyllaert)
20020209.578 <126 (Mamoru Ooishi)
20020209.766 132 (Georg Comello)
20020209.867 128 (Hazel McGee)
20020209.894 130 (Eddy Muyllaert)
20020210.008 130 (Erwin van Ballegoij)
20020210.478 132 (Mamoru Ooishi)
20020210.519 132 (Masashi Nakatani)
20020211.497 132 (Mamoru Ooishi)
20020212.533 132 (M. Hiraga)
20020212.863 131 (Georg Comello)
20020213.824 131 (Georg Comello)
20020213.860 131 (Gary Poyner)
20020213.863 131 (Maciej Reszelski)
20020214.822 131 (Georg Comello)
20020214.824 131 (Eddy Muyllaert)
20020214.919 132 (Reinder J. Bouma)
20020215.488 <126 (Y. Sekino)
20020215.803 128 (Patrick Schmeer) RISING?
20020215.860 129 (Maciej Reszelski) RISING?
GK Per has an orbital period of 1.996803 d. Grazing eclipses can occur
around the following times (cf. Kim et al.'s paper ApJ 384, 269, 1992).
YYYYMMDD hh:mm:ss (UT, geocentric)
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20020215 02:32:28
20020217 02:28:07
20020219 02:23:47
20020221 02:19:26
20020223 02:15:06
20020225 02:10:45
20020227 02:06:25
The analysis of quiescent visual observations has shown modulations
with this period very clearly (analysis by J. Greaves and T. Kato):
http://ftp.kusastro.kyoto-u.ac.jp/pub/vsnet/Novae/GK_Per/pdm.gif
http://ftp.kusastro.kyoto-u.ac.jp/pub/vsnet/Novae/GK_Per/ph.gif
VSNET has created a special mailing list for the campaign in this
rare outburst. One can join the list by sending an e-mail with a line:
SUBSCRIBE vsnet-campaign-gkper
to vsnet-adm@kusastro.kyoto-u.ac.jp
See also the VSNET GK Per page:
http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/Novae/gkper.html
Regards,
Taichi Kato
On behalf of the VSNET Collaboration team
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VSNET (Variable Star Network) is an international variable star observing
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VSNET Home Page: http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/
CCD observations of such targets are a relatively easy task for a 20-40cm
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