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[vsnet-campaign-news 21] News from VSNET 21
*** News from VSNET ***
V402 And, a poorly known dwarf nova, turned out to be an SU UMa-type
currently in a superoutburst. Delta Sco has stopped fading from the
historical outburst.
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 Sep. 26, 2000, as VSNET campaign circulation 504.
[Note a large part of detailed information is posted to vsnet-campaign
sub-lists].
VSNET Weekly Campaign Summary
*** Last week news ***
(new targets)
SN 2000dk (RA = 01h07m23s.52, Dec = +32d24'23".2)
H. Yamaoka reported the Lick KAIT team has discovered a new SN in the
elliptical galaxy NGC 382. The position is about 5" west and 9"
north of the nucleus of NGC 382. The magnitude was 15.8mag on September
19.2 (vsnet-campaign-sn 85).
The follow-up photometry of this SN would be useful for exploring the
nature of it.
V402 And (RA = 00h11m07s.25, Dec = +33d32'36".1)
G. Poyner reported in [vsnet-alert 5268] that M. Mobberley detected
an outburst of this poorly known dwarf nova on September 20 (15.7mag).
T. Vanmunster had <17.0 on a CCD image taken on September 18.
T. Kato confirmed the reported outburst at Ouda Station, Kyoto University
on September 21 (V=15.3; vsnet-campaign 506). He also reported the
clear presence of superhumps in the light curve obtained on September 21.
This revealed V402 And is a new SU UMa-type dwarf nova (vsnet-campaign 508).
H. Yamaoka performed astrometry using Ouda images and determined its precise
position (see above). The magnitude of the coincident USNO star indicates
the outburst amplitude of this star is around mag 4, which is rather small
as a typical SU UMa stars (vsnet-campaign-dn 153). T. Kato reported
the amplitude of the superhumps are almost constant around 0.25mag
(vsnet-campaign-dn 155), and calculated the best candidate of the
superhump period to be 0.0634 d using the data observed at Ouda and by
J. Pietz (vsnet-campaign-dn 161).
The reported magnitude on September 22 is about 15.3 (by M. Simonsen)
(vsnet-campaign-dn 152). More time-series observations are strongly
encouraged.
3C 66A (RA = 02h22m39s.6, Dec = +43d02'08")
The blazar 3C 66A has brightened as reported by the G. Poyner's
observation on September 21 (14.5mag; vsnet-campaign-blazer 68).
V452 Cas (RA = 00h52m20s.87, Dec = +53d52'17".6)
The SU UMa-type dwarf nova V452 Cas is undergoing an outburst, which
was detected by C. P. Jones and G. Poyner on September 20 (15.1 and 15.2mag).
The last superoutburst of V452 Cas was observed in 1999 November
(vsnet-campaign 507). T. Kato reported on September 21 that the object
looked somewhat fainter than the reported magnitudes (vsnet-campaign-dn 150).
He also detected superhumps in the light curve on September 21.
This concludes that the present outburst is a genuine superoutburst
(vsnet-campaign 510).
The reported magnitude on September 23 is 15.2mag (by C. P. Jones)
(vsnet-campaign-dn 158). More time-series observations are strongly
encouraged.
BF Ara (RA = 17h38m10s.40, Dec = -47d10'43".4)
BF Ara is undergoing a bright outburst, as reported by R. Stubbings
on September 24 (13.9mag). As earlier suspected, this star may be an
SU UMa-type system related to ER UMa stars (vsnet-campaign 511).
Time-resolved photometry during such bright outbursts is strongly
encouraged.
V730 Sgr (RA = 19h23m00s.79, Dec = -28d29'29".2)
The dwarf nova V730 Sgr is undergoing a bright outburst as reported by
R. Stubbings on September 24 (13.6mag). During the August outburst,
N. Butterworth reported time-series photometry which yielded slow waves
in the light curve. This finding does not exclude the possibility of the
object being an SU UMa-type dwarf nova (vsnet-campaign 512). T. Kato
confirmed the outburst on September 25 (V=13.5; vsnet-campaign-dn 162).
Observations during the present outburst is also encouraged.
SN in UGC 11198 (RA = 18h18m58s.97, Dec = +16d14'53".4)
H. Yamaoka wrote in [vsnet-campaign-sn 92] that the LOSS KAIT team has
discovered a new possible SN in UGC 11198. The position is about 4" west
and 5" south of the nucleus of this nearly edge-on spiral (Sab) galaxy.
The reported magnitude of the new star (mag about 16.1 at Sep. 24.1,
and mag about 18.5 at Sep. 16.1) suggest that this SN would be a
bright one, and probably in the rising phase (vsnet-campaign-sn 92).
(continuous targets)
PQ Aql (RA = 19h53m05s.18, Dec = +12d59'02".1)
T. Kato reported the reported outburst has almost terminated on September
21, and the object was observed fainter than V=17 (vsnet-campaign-dn 148).
NSV08383 (RA = 17h16m53s, Dec = -65d32'42")
The current outburst has terminated as reported by R. Stubbings on
September 24 (15.2mag) (vsnet-campaign-dn 149, 160).
SN 2000dj (RA = 01h56m40s.63, Dec = +34d10'12".4)
The current magnitude is around 16.8mag (vsnet-campaign-sn 87).
BL Lac (RA = 22h02m42.86s, Dec = +42d16'37.6")
Btihtenings and short-term large variations were observed in the last
week (vsnet-campaign-blazer 67, 69, 70, 72). The reported magnitudes
during the last week are 13.9 - 14.6.
Close monitorings are encouraged.
V803 Cen (RA = 22h02m42.86s, Dec = +42d16'37.6")
The object again brightened at 13.4mag on September 21 according to
R. Stubbings'observations (vsnet-campaign-dn 151). The magnitude
on September 24 reported by R. Stubbings is 13.6.
MV Lyr (RA = 19h07m15s.93, Dec = +44d01'10".7)
The slow fading of this object continues. The magnitude on September 19
reported by M. Simonsen is 14.4 (vsnet-campaign 505).
Delta Sco (RA = 16h00m19s.9, Dec = -22d37'17")
On the basis of observations by B. Fraser and S. Otero, S. Otero
reported delta Sco has stopped fading at around 2.13 mag
(vsnet-campaign-be 56).
SN 2000cx (RA = 01h24m46s.15, Dec = +09o30'30".9)
The fading trend continues. The magnitude on September 24 reported
by D. Rodriguez is 16.50 (vsnet-campaign-sn 93).
PKS2005-489 (RA = 20h05m47s.4, -48d58'45".0)
This blazer is still brighter. The magnitude on September 24 reported
by A. Pearce is 12.3mag (vsnet-campaign-blazer 71).
V3774 Sgr (RA = 18h41m41s.34, Dec = -32d54'35".7)
T. Kato reported the outburst which was detected on September 15 had
apparently faded (visible, but probably below mag 16). This indicates
that the current outburst is coming to an end (vsnet-campaign-dn 157).
*** Future schedule ***
EF Eri (HST observation)
Researchers at Goettingen have a plan to observe this AM Her star
with HST in near future, and strongly want to know the current state
of this star. D. Nogami provides the location (RA: 03h 14m 13.21s,
Dec: -22o 35' 42.7'' (J2000)) and the sequence
(http://ftp.nofs.navy.mil/pub/outgoing/aah/sequence/sumner/eferi.seq)
in [vsnet-campaign 467].
For more detailed information, please contact with D. Nogami
(daisaku@uni-sw.gwdg.de).
V446 Her campaign (throughout this summer)
Boris T. Gaensicke organize a campaign on the post nova V446 Her (V~18).
Their aim is to obtain a *good* contiguous light curve of V446 Her that
covers 2-3 dwarf nova-like outbursts of the system, in order to compare
its outburst characteristics to those of ``normal'' dwarf novae.
They invite those of you equipped with a CCD camera to obtain a couple
of images of V446 Her per night throughout the next three months, say,
until the end of September.
For more information, please see [vsnet-campaign 325] or contact
with Boris T. Gaensicke (boris@uni-sw.gwdg.de).
In [vsnet-campaign 446].....
"Now, one and a half month later, we present a preliminary lightcurve
which you can find at
"http://alpha.uni-sw.gwdg.de/~mschrei/v446her/light.gif".
The light curve is very interesting, ......
Hence we again invite those of you equipped with a CCD camera to
obtain a couple of images of V446Her per night at least until the
end of September. Together we can rewrite the post nova scenario !!!"
*** General information ***
V452 Cas
B. Sumner presents a revised sequence, see [vsnet-campaign 509]
SN 2000dk
D. W. Bishop showed URLs where we can see the SN 2000dk images.
http://vsnet.ggw.org/asras/supernova.html#2000dk
http://vsnet.ggw.org/asras/sn2000/sn2000dk.html
[vsnet-campaign-sn 89]
(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