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*** News from VSNET ***
The SU UMa-type dwarf nova, 1RXP J113123+4322.5, has shown strange
period changes of superhumps.
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 March 25, 2003, as VSNET campaign
circulation 1377
[Note a large part of detailed information is posted to vsnet-campaign
sub-lists].
VSNET Weekly Campaign Summary
*** Last week news ***
(new targets)
SN 2003cg (RA = 10h14m15s.97, Dec = +03d28'02".5)
SN 2003cg is hosted by NGC 3169, a nearby spiral galaxy. The
expected maximum for typical SN Ia is mag about 12.8, indicating
that it may become a very bright SN. NGC 3169 has produced SN IIL
1984L, whose maximum was B=15.2 (vsnet-campaign-sn 585).
SN 2003ch (RA = 07h17m57s.92, Dec = +09d41'34".9)
SN 2003ch is hosted by UGC 3787, an elliptical (or lenticular)
galaxy which is a western component of the galaxy pair
(vsnet-campaign-sn 585).
SN 2003ci (RA = 11h10m23s.83, Dec = +04d49'35".9)
SN 2003ci is hosted by UGC 6212, a disturbed spiral galaxy
interacting with the southern smaller one. The new object is
superimposed on the southern arm. The expected maximum for typical
SN Ia is comparable with the discovery magnitude (17.5: mag)
(vsnet-campaign-sn 585).
GH Gem (RA = 07h04m05s.49, Dec = +12d02'29".1)
The object is now in outburst. It was around 12.5mag in mid-March
(vsnet-campaign-symbio 52).
(continuous targets)
1RXP J113123+4322.5 (RA = 11h31m22s.426, Dec = +43d22'38".51)
Superhumps decreased in amplitude, and the period derivative was
statistically positive, at a mean rate close to dot(P)/P =
+8*10^(-5), as T. Kato reported on March 18, 19, and 20
(vsnet-campaign-dn 3547, 3548, 3550). However, the superhump period
then suddenly showed a large decrease. This change makes a clear
contrast to SW UMa during the 1996 superoutburst, but bear more
resemblance to V1028 Cyg or AL Com (vsnet-campaign-dn 3552).
DM Dra (RA = 15h34m12s.13, Dec = +59d48'31".9)
A. Oksanen reported that the object became very faint (<19.0mag)
on March 21 (vsnet-campaign-dn 3551).
MKN 421 (RA = 11h04m27s, Dec = +38d12'32")
G. Poyner reported on March 16 that MKN 421 (blazar) was
exceptionally faint (14.2mag; vsnet-campaign-blazar 298). The faint
state was confirmed and continues on March 18 and 19
(vsnet-campaign-blazar 299).
V603 Aql (RA = 18h48m54s.6, Dec = +00d35'03")
D. West reported that the object showed weak H_alpha emission
(vsnet-campaign-nova 1175).
GSC 6248:1255 (RA = 17h37m22s.694, Dec = -16d21'11".09)
D. West reported that his H_alpha observation indicated no H_alpha
emission (vsnet-campaign-nova 1173).
R CrB (RA = 15h48m34s.40, Dec = +28d09'23".7)
The object has started brightening (vsnet-campaign-rcb 119).
V2540 Oph (RA = 17h37m34s.36, Dec = -16d23'18".4)
D. West reported that his observation indicated H_alpha emission
(vsnet-campaign-nova 1173).
V854 Cen (RA = 14h34m49s.8, Dec = -39d33'18")
S. Otero reported that this active RCB star has faded again. It
was fainter than 12.0mag on March 22, while it was 9.6 mag five days
ago (vsnet-campaign-rcb 120).
*** Future schedule ***
eta Car: The next "shell event"/X-ray eclipse
M. Corcoran reported the event will occur this summer.
Coordinated ground-based observations of eta car along with the
X-ray observations would be really important.
For more information:
Latest X-ray light curve:
http://lheawww.gsfc.nasa.gov/users/corcoran/eta_car/etacar_rxte_lightcurve/
[vsnet-campaign-sdor 23, 24,
25, 26, 28, 29]
[vsnet-campaign-xray 172]
Light curve provided by S. Otero:
http://ar.geocities.com/varsao/Curva_Eta_Carinae.htm
[vsnet-campaign-sdor 22]
The 2003 Gamma Ray Burst conference
Hosted by Los Alamos,
in Santa Fe, New Mexico (USA), between September 8 and 12, 2003
http://grb2003.lanl.gov/
[vsnet-campaign-grb 13]
WEBT campaign on Mkn 421
M. Villata announced possible WEBT campaign on Mkn 421, in
December 2002 and February-March 2003, to be carried out during
multifrequency campaigns.
The relevant information on the MW campaign of December 2-16 is at
the VERITAS site <http://veritas.sao.arizona.edu> .
[vsnet-campaign-blazar 287]
[vsnet-campaign-blazar 288]
SUPERNOVAE (10 YEARS OF SN1993J)
22-26 April 2003, Valencia, Spain
Web site: http://vsnet.uv.es/2003supernovae/ [vsnet-campaign-sn 342]
[vsnet-campaign-sn 452]
[vsnet-campaign-sn 512]
*** General information ***
V838 Mon
Multi-color photometry by S. Kiyota, see [vsnet-campaign-v838mon
417]
V4742 Sgr
GSC6846.6
V-band photometry by D. West, see [vsnet-campaign-nova 1176]
Book information: New Views on Microquasars
[vsnet-campaign-xray 201]
(This summary can be cited.)
Regards,
Makoto Uemura
Return to the Daisaku
vsnet-adm@kusastro.kyoto-u.ac.jp
