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[vsnet-campaign-news 31] News from VSNET 31
*** News from VSNET ***
The recurrent nova CI Aql has entered the final rapid-decline stage.
The eclipsing SU UMa-type dwarf nova OY Car is now at a supermaximum.
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 Dec. 5, 2000, as VSNET campaign circulation 571.
[Note a large part of detailed information is posted to vsnet-campaign
sub-lists].
VSNET Weekly Campaign Summary
*** Last week news ***
(new targets)
IW And (RA = 01h01m08s.82, Dec = +43d23'27".3)
T. Kinnunen reported on November 27 that the poorly understood
cataclysmic variable IW And was bright at the magnitude of 14.7
(vsnet-campaign 562). C. Kunjaya confirmed the outburst at Gunma Astro.
Obsv. on November 29 (14.82mag; vsnet-campaign 563). He reported on
November 30 that, after reduction, the observation did not show time
variation larger than 0.02 mag in ~3 hours light curve (vsnet-campaign 567).
BF Eri (RA = 04h39m29s.62, Dec = -04d36'10".0)
S. Kerr reported an outburst (12.6mag) of BF Eri on November 29
(vsnet-outburst 1030). R. Ishioka (Kyoto team) confirmed the outburst
at 12.6mag (vsnet-campaign 564, 568). The outburst is now fading.
The current magnitude is around 13.8 (vsnet-campaign-dn 276).
CT Hya (RA = 08h51m04s.50, Dec = +03d07'43".5)
As reported by R. Stubbings et al., the SU UMa-type dwarf nova CT Hya is
undergoing an outburst. The last superoutburst was observed in 1999
February, when the VSNET Collaboration team (Kato, Kiyota, Novak and
Matsumoto) detected superhumps with a period of 0.06643 d. However,
some curious O-C behavior (or large change in superhump phase) was noted.
The outburst is still ongoing, the current magnitude is around 14.3
(vsnet-campaign-dn 274, 280).
SN 2000ev (RA = 06h47m52s.0, Dec = +84d10'02".2)
SN 2000ev was discovered by F. Manzini on November 27.10 at mag 16.5
(IAUC 7529). The reported position is only the offsets: 4".5 west and
19" north of the nucleus of the tilted spiral(?) galaxy UGC 3500.
The spectroscopy shows that it seems to be of young type IIn. The expected
maximum of normal SN Ia is about mag 15.5 (vsnet-campaign-sn 118).
SN 2000ex (RA = 03h42m11s.71, Dec = -27d51'48")
SN 2000ex was discovered by KAIT team (IAUC 7530). It has been mag
17.6-17.8 between Nov. 17.4 - 27.3, and was revealed as of type II
(vsnet-campaign-sn 118).
SN 2000ew (RA = 11h40m58s.52, Dec = +11d27'55".9)
According to IAUC 7530, T. Puckett and his colleague discovered a
bright SN (discovery mag 14.9) in the very neighbouring galaxy.
The position is about 2" west and 21" south of the center of the nearly
face-on spiral (SA(rs)c) galaxy NGC 3810. NGC 3810 has produced
SN Ib 1997dq which was discovered at mag 15.0 after maximum.
The recession velocity of this galaxy is about 900km/s, so it can be as
near as the Virgo cluster. If so, the typical SN Ia will reach mag 12 or
so at the maximum (vsnet-campaign-sn 119).
SN 2000ey (RA = 23h19m25s.20, Dec = +05d54'21".1)
The KAIT team discovered mag 15 SN Ia in the evening sky.
The position is 0".6 east and 1".2 south of the nucleus of the odd shaped
spiral? galaxy IC 1481. The spectroscopy on Nov. 29 has revealed that
this SN is normal type Ia around the maximum light. The recession velocity
of the host is 6118 km/s from NED, so the expected maximum is mag 16.2
(vsnet-campaign-sn 120).
V1504 Cyg (RA = 19h28m55s.87, Dec = +43d05'39".9)
As reported by M. Simonsen, the SU UMa-type dwarf nova V1504 Cyg showed
an outburst on November 23 at 14.4mag (vsnet-campaign-dn 257).
V503 Cyg (RA = 20h27m15s.61, Dec = +43d41'45".5)
M. Simonsen reported a new outburst of V503 Cyg at the magnitude of 14.0
on November 25. C. Kunjaya reported that the observation of V503 Cyg on
November 29 at Gunma Astronomocal Observatory shows a clear light variation
with amplitude about 0.2 mag and period 116 minutes (vsnet-campaign-dn 263).
The outburst is still ongoing, and the current magnitude is around 14.2
(vsnet-campaign-dn 265).
V591 Cen (RA = 12h42m18s.56, Dec = -33d33'44".2)
As reported by R. Stubbings on December 1, the dwarf nova V591 Cen
is undergoing a relatively rare outburst at 14.6mag. The last outburst
was observed in 1999 July (mv=14.3, Stubbings), which slowly faded.
The outburst still continues. The current magnitude is around 14.8
(vsnet-campaign-dn 277).
TY PsA (RA = 22h49m40s.31, Dec = -27d06'54".3)
R. Stubbings reported an outburst (11.9mag) of TY PsA on December 1
(vsnet-outburst 1058). The outburst is still ongoing. The current
magnitude is around 11.7 (vsnet-campaign-dn 275).
SN 2000ez (RA = 11h57m45s.75, Dec = +32d17'49".1)
M. Armstrong discovered a supernova (mag 16.8) on November 24.
To date, magnitudes of 16.9C and 17.5R were reported (vsnet-campaign-sn 122).
SN 2000fa (RA = 07h15m29s.88, Dec = +23d25'42".4)
The KAIT team discovered a supernova (mag about 17.5) on November 30.
The position written on IAUC 7533 seems to be that of the foreground star.
The correct position (written above) is 6".6 east and 4".2 north of the
nucleus of UGC 3770 (vsnet-campaign-sn 122).
(continuous targets)
CI Aql (RA = 18h52m03.6s, Dec = -01d28m38.9s)
As reported in IAUC 7528 (K. Matsumoto and T. Kato), the recurrent
nova CI Aql has apparently entered the final rapid-decline stage
(vsnet-campaign-nova 93). The current magnitude seems to be fainter
than 14.2 (vsnet-campaign-nova 93).
EK TrA (RA = 15h14m00s.19, Dec = -65d06'17".1)
The SU UMa-type dwarf nova EK TrA started fading from the superoutburst.
The magnitudes of 13.4: and 13.6 were reported by P. Nelson and
R. Stubbings, respectively on November 27 (vsnet-campaign-dn 256).
OJ 287 (RA = 08h51m57s, Dec = 20d17'59")
The bright state continues. The current magnitude is around 14.5
(vsnet-campaign-blazar 101, 102, 105).
SN 2000el (RA = 22h28m26s.62, Dec = +17d08'51".2)
SN 2000el was independently discovered by KAIT team, and it was revealed
that this SN was first detected on October 23.1 and is of normal type II.
The photometry is quite difficult because it is very close to the nucleus
of the host galaxy (vsnet-campaign-sn 118).
V803 Cen (RA = 13h23m44.5s, Dec = -41d44'30".1)
The outburst continues. The current magnitude is around 13.7
(vsnet-campaign-dn 267). The observation by A. Pearce showed 14.2mag
on December 3, which indicates possibly fading (vsnet-campaign-dn 278).
SN 2000er (RA = 02h24m32s.54, Dec = -58d26'18".0)
SN 2000er was observed as mag 15.4CR on November 28
(vsnet-campaign-sn 118).
OY Car (RA = 10h06m22s.46, Dec = -70d14'04".4)
The eclipsing SU UMa-type dwarf nova OY Car rose to full maximum.
The last superoutburst occurred in 2000 February (vsnet-campaign-dn 255).
The superoutburst is still ongoing and the current magnitude is around
12.6 (vsnet-campaign-dn 266, 269, 272, 279).
BL Lac (RA = 22h02m42.86s, Dec = +42d16'37.6")
The striking activity still continues (vsnet-campaign-blazar 100).
During the last week, a slightly fainter magnitude (14.5mag) was reported
by G. Poyner (vsnet-campaign-blazar 103). The observation by M. Verdenet
showed 13.4mag on December 3, which may indicate brightening again
(vsnet-campaign-blazar 104).
*** General information ***
SN 2000eo
Sequence reported by K. Krisciunas (vsnet-campaign-sn 121), see
http://vsnet.astro.washington.edu/kevin/apo.html
OY Car
Eclipse ephemeris, see [vsnet-campaign-dn 270]
V347 Pup
Eclipse ephemeris, see [vsnet-campaign 570]
SN 2000er
Corrigendum:
In [vsnet-alert 5389] and [vsnet-campaign-sn 113],
"According to IAUC 9132" should be read "According to IAUC 7528".
[vsnet-campaign-sn 116]
SN 2000el
Corrigendum:
In [vsnet-campaign-sn 111], [vsnet-campaign 561], and
[vsnet-campaign-news 30],
the discoverer of SN 2000el should be read "T. Puckett".
[vsnet-campaign-sn 117], [vsnet-campaign 565]
(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