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[vsnet-campaign-news 37] News from VSNET 37
*** News from VSNET ***
V445 Pup (= possible nova Pup 2000) is showing strong oscillations.
UV Per and RZ Leo experienced a rebrightening after the superoutburst.
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 Jan. 16, 2001, as VSNET campaign circulation 690.
[Note a large part of detailed information is posted to vsnet-campaign
sub-lists].
VSNET Weekly Campaign Summary
*** Last week news ***
(new targets)
AM Her (RA = 18h16m13s.4, Dec = +49d52'03".1)
The polar prototype AM Her has definitely entered a faint
(low) state. It now seems to be fainter than 14.0mag.
The last (short) faint state was observed in 2000 April-May
(vsnet-campaign 682).
SN 2000G (RA = 09h09m33s.18, Dec = +50d16'51".3)
SN 2001G has been discovered by M. Armstrong on January 8.051
at mag 16.1, and 4 days later it has brightened to mag 15.2.
The location is 2" east and 4" south of the center of dim (mag 16)
galaxy MCG +08-17-43. NED does not give the type of the galaxy
and its recession velocity, but it seems to be a nearly edge-on spiral.
Several foreground stars are there around the galaxy. The new object
is quite near to the central bright part (vsnet-campaign-sn 131).
V344 Ori (RA = 06h15m20s.18, Dec = +15d27'59".2)
As reported by R. Stubbings on January 15, the dwarf nova
V344 Ori is reported to be undergoing a relatively rare,
bright outburst. The last outburst was reported in 1999 November
(mv=14.0), but the present outburst is the brightest in recent years.
(continuous targets)
RX J0944.5+0357 (RA = 09h44m31s.8, Dec = +03d58'06")
Time-series photometry provided by S. Kiyota on January 5
and 6 is available at [vsnet-campaign-data 58 and 59].
The object faded by nearly 1 mag between January 5 and 6.
T. Kato commented that the rapid fading suggests that the object
may be a short-period system, or even an SU UMa-type star in
normal outburst (vsnet-campaign 667).
SN 2001B (RA = 04h57m19s.24, Dec = +78d11'16".5)
K. Kadota and T. Vince provided CCD images on January 6 at
his web page and on January 12 at VSNET ftp site, respectively
(see below "General Information"; vsnet-campaign-sn 127, 129).
The object now become about 1mag brighter than its discovery
magnitude (15.5C:) (vsnet-campaign-sn 128, 130).
SN 2001C (RA = 06h59m36s.10, Dec = +59d31'01".6)
K. Kadota, T. Vince, and J. Hambsch provided CCD images on
January 6 at his web page and on January 12 and 13 at VSNET ftp
site, respectively (see below "General Information";
vsnet-campaign-sn 127, 129, 132).
V445 Pup (RA = 07h37m56s.88, Dec = -25d56'59".1)
(= Possible Nova in Pup)
An hour run on January 6/7 by G. Masi yields no particular
fluctuations larger than 0.1 mag (vsnet-campaign-nova 146).
S. Otero reported a fading to 9.7mag on January 9 after several
days at 9.1mag (vsnet-campaign-nova 148) and commented about
some sequence problems (vsnet-campaign-nova 147; see also
vsnet-campaign-nova 150; vsnet-campaign 668). The object somewhat
recovered on January 9 and 10 (vsnet-campaign-nova 151, 152).
S. Otero reported it is oscillating stronger as seen in his
January 11 observations (vsnet-campaign-nova 153, 154).
The object was given an official GCVS name V445 Pup
(vsnet-campaign-nova 155). S. Otero reported the object on
January 12 was rather quiet at 9.1mag (vsnet-campaign-nova 156, 157, 159).
A short-term fading was detected on January 13 (vsnet-campaign-nova 160).
On January 15, a fading to 9.7mag was observed (vsnet-campaign-nova 162).
RZ Leo (RA = 11h37m22s.27, Dec = +01d48'58".9)
The Ic-band observations on January 6 by S. Kiyota are available
at [vsnet-campaign-data 57] (vsnet-campaign 666). From the
observation at Kyoto on January 8 and Kiyota's data, T. Kato
reported the decline rate has become apparently slower
(vsnet-campaign 669). The Kyoto observation on January 11
(by Uemura et al.) shows that RZ Leo has apparently stopped
fading (vsnet-campaign 671). On January 12, R. Ishioka, at Kyoto,
found a re-brightening (vsnet-campaign 672). T. Kato mentioned the
interval between the fading from the main superoutburst and the
rebrightening is only ~5 days, which is one of the shortest ever
observed in SU UMa-type dwarf novae (vsnet-campaign 673).
The Kyoto team and S. Kiyota obtained a nearly continuous light
curve of the rebrightened RZ Leo on January 11 in which the object
returned to its pre-fading magnitude, as on January 4. Although
low-amplitude variations were present, superhumps were less prominent
than on January 4 (vsnet-campaign 674). The Kyoto data and
S. Kiyota's data on January 12 shows that the object had not yet
entered the rapid decline from the rebrightening (vsnet-campaign 680, 681).
The Kyoto observation on January 13 (Ishioka et al.) has shown
that RZ Leo entered the rapid decline stage (vsnet-campaign 684).
The Kyoto observation (observer Uemura) on January 14 confirms that
the rapid fading of RZ Leo stopped. The brightness level above
quiescence is rather reminiscent of the inter-rebrightening period
of the WZ Sge-type star EG Cnc (vsnet-campaign 687).
UV Per (RA = 02h10m13s.58, Dec = +57d11'26".8)
The Kyoto observation on January 10 (by Iwamatsu et al.) shows
that UV Per has apparently stopped fading (vsnet-campaign 670).
On January 12, R. Ishioka found its rebrightening (vsnet-campaign 675).
T. Kato mentioned that the interval between the fading from the
main superoutburst and the rebrightening is about 7 days, which
is a relatively typical value for SU UMa-type rebrightening
(vsnet-campaign 676). T. Vanmunster also reported the rebrightening
to 14.3mag on January 12 (vsnet-campaign 677, vsnet-campaign-dn 393).
The Kyoto data on January 12 shows a rapid, smooth fading.
The rate of decline amounts to 1.7 mag/d, which is one of the
fastest time-scales observed in UV Per. There is no evidence of
large-amplitude superhumps (vsnet-campaign 679, vsnet-campaign-dn 394).
J. Pietz confirmed the same trend from his own observation on
January 12 (vsnet-campaign 683). The rapid fading trend was ongoing
on January 13 (vsnet-campaign-dn 395, vsnet-campaign 685).
The Kyoto team (observer Uemura) obtained a continuous coverage
of UV Per on January 14, in which the most remarkable feature is
the presence of large-amplitude modulations (up to 0.5 mag) with
a possible period of ~4 hours (vsnet-campaign 686).
BL Lac (RA = 22h02m42.86s, Dec = +42d16'37.6")
BL Lac is fading. The current magnitude seems to be around
V=15.0 (by R. Rodriguez on January 14)(vsnet-campaign-blazar 125).
TV Col (RA = 05h29m25s.5, Dec = -32d49'05".2)
The outburst on January 7 have rapidly terminated
(vsnet-campaign-ip 32, 33).
3C 66A (RA = 02h22m39s.6, Dec = +43d02'08")
The bright state continues. The current magnitude is
around 14.1 (vsnet-campaign-blazar 124).
Delta Sco (RA = 16h00m19s.9, Dec = -22d37'17")
The bright state continues (vsnet-campaign-be 77).
V803 Cen (RA = 13h23m44.5s, Dec = -41d44'30".1)
The bright outburst is ongoing (vsnet-campaign-dn 392).
WY Tri (RA = 02h25m12s.08, Dec = +33d00'31".5)
T. Vanmunster informed a manuscript on December 2000
outburst of WY Tri has been submitted to IBVS and also posted
to [vsnet-preprint 13] (vsnet-campaign 678).
*** Future schedule ***
TV Col campaign conducted by A. Retter (2001 January 2 - 15):
"Recently using previously published data, we discovered evidence for
another periodicity in the light curve of TV Col. The 6.4-h period would
be the longest recorded positive superhump. To confirm this period, I'll
carry out continuous photometry on TV Col during two weeks in January
(2-15) using the 0.75-m reflector with the UCT CCD in Sutherland, South
Africa.
I am calling for a campaign on TV Col during these nights. As the
candidate periodicity is relatively long, multi-longitude continuous
monitoring of the object is extremely important to reduce the aliasing
problem. So, if you can observe the object for at least ~4 h (preferably
more than one 6.4-h cycle), please let me know."
for more information, see [vsnet-campaign 579],[vsnet-campaign-ip 15]
*** General information ***
SN 2001B
CCD image provided by K. Kadota:
http://vsnet.astroarts.com/ageo/supernova/
[vsnet-campaign-sn 127]
CCD image provided by T. Vince:
http://ftp.kusastro.kyoto-u.ac.jp/pub/vsnet/SNe/sn2001b/sn2001b.gif
[vsnet-campaign-sn 129]
SN 2001C
CCD image provided by K. Kadota:
http://vsnet.astroarts.com/ageo/supernova/
[vsnet-campaign-sn 127]
CCD image provided by T. Vince:
http://ftp.kusastro.kyoto-u.ac.jp/pub/vsnet/SNe/sn2001c/sn2001c.gif
[vsnet-campaign-sn 129]
CCD image provided by J. Hambsch:
http://ftp.kusastro.kyoto-u.ac.jp/pub/vsnet/SNe/sn2001c/sn2001c_300_s.jpg
[vsnet-campaign-sn 132]
WY Tri
preprint on December 2000 outburst, see [vsnet-preprint 13]
[vsnet-campaign 678]
(This summary is reproduction free.)
Regards,
Makoto Uemura
vsnet-adm@kusastro.kyoto-u.ac.jp
Return to Daisaku Nogami
vsnet-adm@kusastro.kyoto-u.ac.jp
VSNET Home Page