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[vsnet-campaign-news 27] News from VSNET 27
*** News from VSNET ***
The eclipse of Delta Vel was observed on November 1 as predicted.
A 17.6-mag nova was discovered in M31. IX Dra turned out to be a
short-period SU UMa-star.
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 Nov. 7, 2000, as VSNET campaign circulation 554.
[Note a large part of detailed information is posted to vsnet-campaign
sub-lists].
VSNET Weekly Campaign Summary
*** Last week news ***
(new targets)
SN 2000dx (RA = 02h18m26s.88, Dec = +05d39'02".0)
H. Yamaoka forwarded a content of IAUC 7514 which reports a new
supernova, SN 2000dx. SN 2000dx was discovered on October 30.3 UT at mag
about 17.3 and became slightly brighter on the next day. The position is
about 8" east and 12" south of the nucleus of ring-shaped spiral galaxy
UGC 1775. The spectrum of SN 2000dx shows that it is of type Ia a few days
before maximum. Typical SN Ia on this galaxy is mag about 17.1. If it
will rise from the discovery magnitude, it should have a bright nature.
Nova in M31 (RA = 00h42m57s.17, Dec = +41d07'15".4)
The Remanzacco Observatory team found a nova in M31 at the magnitude of
17.6 on October 22.9. It was not present on other frames of the same
region taken with our instrumentation on September 1, 7, 8, 9 and 22
(vsnet-campaign-nova 88). Following this, F. Ewalt reported no object
can be seen in his image taken September 5 and there is a "possible"
stellar object dimmer than magnitude 18 in his October 24 image
(vsnet-campaign-nova 89). The Remanzacco Observatory team again performed
CCD observation on November 1 and estimated the magnitude of 18.7
(vsnet-campaign-nova 87).
V2051 Oph (RA = 17h08m19.1s, Dec = -25d48m31.1s)
According to R. Stubbings on October 27, the eclipsing SU UMa-type dwarf
nova V2051 Oph is undergoing an outburst. The brightness suggests a
superoutburst, however it faded rather rapidly. On November 5, R. Stubbings
and P. Nelson reported the magnitudes fainter than 12.2 and 12.5,
respectively (vsnet-campaign-dn 237).
TY Psc (RA = 01h25m36s.87, Dec = +32d23'05".3)
As reported by J. Ripero on October 28, the SU UMa-type dwarf nova TY Psc
is undergoing a superoutburst (vsnet-campaign 545). The outburst is now
undergoing, and the current magnitude is about 12.6 (vsnet-campaign-dn 235).
V344 Pav (RA = 19h16m10.21s, Dec = -62d35'54".4)
The dwarf nova V344 Pav is in outburst. R. Stubbings reported the
magnitude of 14.4 on November 3. The last outburst was reported
in 2000 July. Since little is known about this object, we encourage
time-resolved photometry (vsnet-campaign 548).
HX Peg (RA = 23h40m23s.37, Dec = +12d37'44".0)
The observation by R. Stubbings on November 3 (14.0: mag) indicates
possible brightening of this object. No bright outbursts have been
observed since the early October outburst. This star may be experiencing
a low state like that of RX And. More observations are clearly needed
(vsnet-campaign 549).
V1028 Cyg (RA = 20h00m52.13s, Dec = +56d56'22.3")
The SU UMa-type dwarf nova V1028 Cyg is in outburst as reported by
G. Poyner at 13.9mag on November 3. The last outburst was in 1999 September.
Follow-up observations of the present outburst is also highly encouraged
(vsnet-campaign 550). The current magnitude is about 14.3mag
(vsnet-campaign 552, -dn 233).
IX Dra (RA = 18h12m32s.2, Dec = +67d04'41")
T. Vanmunster performed CCD observations on IX Dra whose outburst was
reported on October 25 by M. Reszelski and the resulting real-time light
curve clearly shows the presence of a 0.22 mag modulation, to be attributed
to superhumps (vsnet-campaign 551). Based on his 6.45hr observation,
the superhump period is calculated to be 0.068d. Observations from other
observatories therefore would be highly appreciated, to further study the
outburst behaviour of this interesting UGSU type CV (vsnet-campaign 551).
As reported by T. Kinnunen, the September outburst lasted at least for four
days, which might suggest another superoutburst. If the September outburst
was a genuine superoutburst, the interval of subsequent superoutbursts
becomes as short as 49 d, which is pretty close to that of ER UMa
(vsnet-campaign 553).
(continuous targets)
Delta Vel (RA = 08h44m42s.1, Dec = -54d42'30")
S. Otero reported results by A. Jansen on October 31 - November 1 and 2,
which detected an eclipse at the expected time (vsnet-campaign-deltavel 11).
He also calculated a candidate of the period to be 45.15667 day and predict
the next eclipse on November 21 18.30 (UT) and December 17 2.40 (UT)
(vsnet-campaign-deltavel 13). B. Fraser reported a little dimmer magnitude
of V=1.99 on November 4 1.30 (UT) (vsnet-campaign-deltavel 14).
B. Fraser reported his November 4 observation yields V=2.01mag and commented
it may be showing some variability or the given brightest of 1.95 is
slightly wrong (vsnet-campaign-deltavel 17).
KW And (RA = 02h35m17s.991, Dec = +41d14'02".47)
T. Kato and H. Iwamatsu confirmed the magnitude is going down to about
17.5mag on November 1st (vsnet-campaign-dn 228).
RX J2315.5-3049 (RA = 23h15m31s.934, Dec = -30d48'45".53)
T. Kato and H. Iwamatsu confirmed the magnitude is going down to about
16mag on November 1st (vsnet-campaign-dn 226). Although superhumps
were observed, the outburst was terminated (vsnet-campaign-dn 230).
IP Peg (RA = 23h23m08s.7, Dec = +18d24'59".1)
M. Richmond commented the position written in the last VSNET Weekly
Campaign Summary and in SIMBAD are incorrect (vsnet-campaign-dn 227).
The above position is cited from Ritter H., & Kolb U. (1998), which
presents the position consistent with the position roughly estimated by
M. Richmond. The current long bright outburst began fading.
The current magnitude is about 14.8 (vsnet-campaign-dn 236).
BL Lac (RA = 22h02m42.86s, Dec = +42d16'37.6")
The striking activity is still ongoing. During the last week,
14.1-14.6mag were reported (vsnet-campaign-blazar 89).
3C 66A (RA = 02h22m39s.6, Dec = +43d02'08")
The bright state is still ongoing. During the last week, 14.3-14.6mag
were reported (vsnet-campaign-blazar 88).
*** General information ***
Delta Vel
S. Otero suggests some comparison stars for observation in
[vsnet-campaign-deltavel 10]
V2051 Oph
eclipse ephemeris, see [vsnet-campaign-dn 238]
Nova in M31
images, see [vsnet-image 22,23,24,25,and 26]
IP Peg
eclipse ephemeris, see [vsnet-campaign-dn 239]
(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
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