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[vsnet-campaign-news 144] News from VSNET
*** News from VSNET ***
A bright supernova, SN 2002bu was discovered.
A nebular shell was confirmed around V838 Mon.
For more detail information about these objects,
see below, "VSNET Weekly Campaign Summary" of the last week.
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VSNET (Variable Star Network) is an international variable star observing
network, covering various areas of novae, supernovae, cataclysmic variables
(CVs), X-ray transients, and other classical eruptive, pulsating, and
eclipsing variables. VSNET is one of invited contributing organizations
to the SkyPub AstroAlert system.
The "News from VSNET", mainly focusing on recent remarkable activities of
CVs and related systems, is issued on a weekly basis, except on occasions
of extremely urgent or transient events.
Please refer to the VSNET Home Page for more details of events and
objects listed.
VSNET Home Page: http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/
VSNET provides a number of mailing lists, on which various news and topics
are discussed. Subscriptions to the VSNET mailing lists are free of charge;
please refer to the instruction on the above page if a reader needs more
information of the list structure.
CCD observations of such targets are a relatively easy task for a 20-40cm
telescope; simply take as many CCD frames (with exposure times 10-30 sec)
as possible, spanning several hours per night. The only requirements are
the weather and your patience! If you need more help on the observing
technique, please feel free to ask on the vsnet-campaign list.
We would sincerely appreciate volunteers who would join the VSNET
Collaboration team to study the wonders of these exotic variable stars.
To join the VSNET campaign collaborative list, send an e-mail to
vsnet-adm@kusastro.kyoto-u.ac.jp (VSNET administrator)
with a line "SUBSCRIBE vsnet-campaign."
(VSNET campaign members are strongly recommended to subscribe to vsnet-alert
at the same time).
Regards,
Taichi Kato
On behalf of the VSNET administrator team
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The following was issued on April 1, 2002, as VSNET campaign circulation 1300
[Note a large part of detailed information is posted to vsnet-campaign
sub-lists].
VSNET Weekly Campaign Summary
*** Last week news ***
(new targets)
SN 2002bs (RA = 13h18m30s.30, Dec = -14d36'31".8)
According to IAUC 7861, J. Y. Wei et al., Beijing Astronomical
Observatory team, discovered an apparent supernova on images
taken on Mar. 11.73 (mag about 15.5) and 23.73 UT (mag about 14.1).
IC 4221, the host galaxy of SN 2002bs, is a somewhat odd-shaped
spiral galaxy. The new object is just superimposed on the nucleus.
It is SN Ia around maximum on Mar. 26.67 (vsnet-campaign-sn 386).
SN 2002bu (RA = 12h17m37s.18, Dec = +45d38'47".4)
SN 2002bu was discovered at 15.5mag on Mar. 28.26 UT at Puckett
Observatory. The position of the SN is about 73" east and 98"
north of the center of the somewhat irregular-shaped galaxy
NGC 4242. NGC 4242 is a member of a nearby group of galaxy called
"Canes Venatici II cloud", whose mean redshift is about 750 km/s.
The expected maximum for the typical SN Ia is mag about 11.7,
and even if it is of type-II, it can become brighter than mag 14
(vsnet-campaign-sn 387). K. Ayani, T. Kawabata, and H. Yamaoka
performed spectroscopy and reported that it shows a flat continuum
with strong and narrow Balmar emission lines, which indicates that
it is of type IIn (vsnet-campaign-sn 391). The object is now at
about 15.3-15.5C mag (vsnet-campaign-sn 388, 390).
CP Dra (RA = 10h15m39s.88, Dec = +73d26'05".4)
J. Pietz detected an outburst (15.3mag) of this long-period
SU UMa-type dwarf nova on March 27. He also detected a superhump
with an amplitude of 0.2-0.25mag on March 28. The Kyoto team
confirmed the outburst and an evolved superhump with an amplitude
of 0.4mag on March 31. The last superoutburst occurred in 2001
February (vsnet-campaign-dn 2213, 2216). The superoutburst is
now ongoing (vsnet-campaign-dn 2214).
Nova Aql 1985 (RA = 19h02m14s.45, Dec = +13d03'04".4)
According to IBVS No. 5246, a missed (likely) nova was
discovered from photographs taken in 1985. The object was 9.65pv
mag at maximum and 18.6:r mag at quiescence. Since the outburst
amplitude seems to be rather small for this fast nova (might be a
recurrent nova candidate), a further search for archival
plates/images might be meaningful (vsnet-campaign-nova 892).
RX J0558.3+6735 (RA = 05h58m18s.0, Dec = +67d53'45")
According to P. A. Dubovsky (vsnet-obs 39223), the
ROSAT-selected cataclysmic variable RX J0558.3+6753 is undergoing
a bright outburst (mv=13.9 on Mar. 31.839 UT). The 2001 outburst
apparently quickly faded (vsnet-campaign-dn 2217, 2221).
P. A. Dubovsky reported that the last outburst (13.9mag)
occurred in 2002 February (vsnet-campaign-dn 2222).
(continuous targets)
CI UMa (RA = 10h18m13s.01, Dec = +71d55'42".8)
The possible superoutbust still continues. The object was
reported to be 14.8:mag on March 31 (vsnet-campaign-dn 2218).
CR Boo (RA = 13h48m55s.42, Dec = +07d57'30".3)
The Kyoto team reported that the object had remained at 13.6mag
without fading since March 21. Such a state without fading is
rather atypical for superoutbursts and is difficult to be explained
with the disk-instability model for dwarf nova outbursts
(vsnet-campaign-dn 2215). The object began fading on March 30.
The atypical plateau lasted for, at least 7 days
(vsnet-campaign-dn 2223).
SN 2002bo (RA = 10h18m06s.51, Dec = +21d49'41".7)
The object is still in a bright maximum at ~13.8-14.0mag
(vsnet-campaign-sn 389).
GK Per (RA = 03h31m12s.50, Dec = +43d54'17".8)
The object started brightening at a roughly constant rate of
0.05mag/d since March 15 (vsnet-campaign-gkper 70, 71, 73, 76).
M. Uemura reported that the 0.006-0.008 d periodicity appeared
to weaken since March 25 while the spin periodicity (~0.004 d)
and 0.0525-d one are still evident (vsnet-campaign-gkper 72, 74).
The 0.0525-d modulations seem to have highly variable profiles
in each cycle, but have high coherent period (vsnet-campaign-gkper
74, 75).
SN 2002ap (RA = 01h36m23s.85, Dec = +15d45'13".0)
A. Gal-Yam et al. estimated the peak time of U- and B-band
flux of SN 2002ap, and reported that the GRB trigger might occur
before January 21 and is likely to have been missed by Hurley et al.
(GCN 1252) (vsnet-campaign-sn2002ap 200).
V803 Cen (RA = 13h23m44s.5, Dec = -41d44'30".1)
The fading from the last bright outburst was terminated by
a new outburst (13.4-13.6mag) on April 1 detected by R. Stubbings
(vsnet-campaign-dn 2219).
V2540 Oph (RA = 17h37m34s.36 Dec = -16d23'18".4)
O. Pejcha reported a significant brightening from V=9.62 on
March 30 to V=8.96 on March 31 (vsnet-campaign-nova 893).
V838 Mon (RA = 07h04m04s.816, Dec = -03d50'50".94)
The object almost remains at about 7.8mag during this week
(vsnet-campaign-v838mon 307, 308, 310, 315, 316, 318). A possible
rising was indicated by some reported observations on March 30-31
(vsnet-campaign-v838mon 317). V. P. Goranskij reported that
Nova 1988 V1006/7 in M31 showed a spectrum which is quite similar
to that of V838 Mon (vsnet-campaign-v838mon 309). A. Henden
reported that the object has faded a bit in the blue, the nebular
shell surrounding it (cf IAUC 7859) is becoming more visible
(vsnet-campaign-v838mon 311, 312, 313, 314).
HL CMa (RA = 06h45m17s.0, Dec = -16d51'35")
A possible small outburst was reported on March 30
(vsnet-campaign-dn 2220).
*** Future schedule ***
NEW X-RAY RESULTS FROM CLUSTERS OF GALAXIES AND BLACK HOLES
34th COSPAR Scientific Assembly
10th to 12th October 2002 - Houston, Texas
For more information, visit the session website:
www.mssl.ucl.ac.uk/www_astro/cospar
[vsnet-campaign-xray 124]
[vsnet-campaign-agn 2]
SUPERNOVAE (10 YEARS OF SN1993J)
22-26 April 2003, Valencia, Spain
Web site: http://vsnet.uv.es/2003supernovae/
[vsnet-campaign-sn 342]
34TH COSPAR - GRB AFTERGLOW PHYSICS
HOUSTON, TX, USA, 10-19 OCTOBER 2002
Main Scientific Organizer (MSO):
Elena Pian - INAF, Astronomical Observatory of Trieste, Italy -
pian@ts.astro.it
http://vsnet.ts.astro.it/topics/topix.html
[vsnet-campaign-grb 1]
MASS-LOSING PULSATING STARS AND THEIR CIRCUMSTELLAR MATTER
Sendai, Japan: May 13-16, 2002
contact to: Dr. M. Seki or wsloc@astr.tohoku.ac.jp
http://vsnet.astr.tohoku.ac.jp/ws2002/
[vsnet-campaign-mira 3]
International Conference on Classical Nova Explosions
Sitges (Barcelona), Spain: 20-24 May 2002
For more detailed information, see http://vsnet.ieec.fcr.es/novaconf
[vsnet-campaign-nova 643]
[vsnet-campaign-nova 666]
Blazar meeting at Tuorla: June 17-21, 2002
for more information, see http://vsnet.astro.utu.fi/blazar02
[vsnet-campaign-blazar 232]
*** General information ***
V838 Mon
U-band image taken by A. Henden:
http://ftp.nofs.navy.mil/pub/outgoing/aah/temp/020327.jpg
[vsnet-campaign-v838mon 311]
Spectroscopic monitoring:
http://perso.wanadoo.fr/sdmorata/V838/V838Mon.html
[vsnet-campaign-v838mon 319]
(This summary can be cited.)
Regards,
Makoto Uemura
vsnet-adm@kusastro.kyoto-u.ac.jp
Return to Daisaku Nogami
vsnet-adm@kusastro.kyoto-u.ac.jp
VSNET Home Page