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[vsnet-campaign-news 15] News from VSNET 15
*** News from VSNET ***
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.
Regards,
Taichi Kato
On behalf of the VSNET administrator team
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Delta Sco information (partly updated contents):
* Charts with magnitudes (created by Tsutomu Watanabe, VSOLJ):
http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/Mail/vsnet-j-deltasco/msg00011.html
(The main text is in Japanese, but the image will look ok).
* Latest light curve (requires Java):
http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/etc/drawobs.cgi?text=SCOdelta
The key VSNET lists on delta Sco are vsnet-be and vsnet-campaign-be.
http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/Mail/vsnet-be/maillist.html
http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/Mail/vsnet-campaign-be/maillist.html
The halo(?) black-hole transine, XTE J1118+480, has finally entered
the rapid decline stage. Intensive observations are strongly encouraged
to follow the subsequent behavior.
Several other dwarf novae are observed in outburst, which are listed
below.
FBS 2351+228 = NSV 26158 is an enigmatic outbursting object whose
nature has not yet been clarified.
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).
Or, look at the list information page for more details:
http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/information.html
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The following was issued on Aug. 13, 2000, as VSNET campaign circulation 427.
[Note a large part of detailed information is posted to vsnet-campaign
sub-lists].
VSNET Weekly Campaign Summary
*** Last week news ***
(new targets)
SN 2000db (RA = 11h53m39s.75, Dec = +47d51'46".6)
H. Yamaoka forwarded and commented on IAUC 7454 which tells that M. Aoki
has discovered a quite bright SN 2000db. The discovery was made on
Aug. 6.498 UT when the SN was mag 14.3. The location is about 20"
northwest of the center of the tilted open-spiral (SA(s)bc) galaxy NGC 3949.
The expected maximum of SN Ia on this distance is about mag 12
(vsnet-campaign-sn 41).
Close monitorings are encouraged.
V1504 Cyg (RA = 19h28m55s.87, Dec = +43d05'39".9)
The SU UMa-type dwarf nova V1504 Cyg seems to exhibit a state of
atypically increased outburst activity since the early August. The short
outburst interval may rival normal outbursts of ER UMa stars
(vsnet-campaign 415).
Observers are strongly urged to monitor the object closely.
V725 Aql (RA = 19h56m43s.61, Dec = +10d49'22".1)
As reported by M. Simonsen and by G. Poyner, and confirmed by C. Jones,
an SU UMa-type dwarf nova, V725 Aql began an outburst on August 8.
The orbital period of V725 Aql estimated from the superhump period is
located at the middle of the period gap (2.5 hr) (vsnet-campaign 417).
The Ouda observing team reported on August 9 that the object was apparently
fainter than the 14.0 mag comparison star (vsnet-campaign 422).
This observation suggested this outburst to be a normal one, however
The object have not completely faded on August 11 (14.7:mag by C. P. Jones)
(vsnet-campaign-dn 106).
Time-series observations are urgently needed to clarify the nature of
this outburst.
FBS 2351+228 (= NSV 26158) (RA = 23h53m51.02s and Dec = +23d09'19.5")
As reported by T. Vanmunster in [vsnet-alert 5176], this poorly known
(and NR: in NSV) object began an outburst (13.9mag on August 9)
(vsnet-campaign 418). T. Kato reported that the previous outburst of
this object was observed in 1999 September with the maximum of 14.3mag,
reported by L. T. Jensen and confirmed by T. Kinnunen (vsnet-campaign 421).
The Ouda observing team obtained multicolor CCD photometry, which seems
to suggest that the outburst is rather red (vsnet-campaign 423).
O. Trondal reported the observation (14.8mag on August 10) and the URL
which includes a picture and a low resolution spectrum (vsnet-campaign 424).
Two nights (August 08/09 and 10/11) of extensive CCD photometry at CBA
Belgium Observatory, have yielded a flat light curve, showing no obvious
modulations (vsnet-campaign 426).
Spctroscopy will be very useful in determining the nature of the object.
SN 2000dc (RA = 20h20m45s.47, Dec = -24d07'57".5)
H. Yamaoka forwarded and commented on IAUC 7476 which tells that
the Lick KAIT team has discovered a mag 16 SN. The position is about 4"
west and 16" south of the nucleus of the barred-spiral (SB(r)b) galaxy
ESO 527-G019. The expected maximum of the typical SN Ia on this distance
(v_r = 3117 km/s for ESO 527-G019) is mag 14.8 (vsnet-campaign-sn 43).
Close monitorings are encouraged.
(continuous targets)
V730 Sgr (RA = 19h23m00s.79, Dec = -28d29'29".2)
The rare outburst of V730 Sgr have faded ( <14.0mag on August 7 by
P. Williams) (vsnet-campaign 416). Now it is at quiescent state.
DH Aql (RA = 19h26m12s.05, Dec = -10d15'21".4)
The Ouda observing team reported on August 9 that the object seems to be
slightly fainter than on the previous night. This may suggest that the
superoutburst was close to the termination (vsnet-campaign-dn 101).
The data on August 9 by N. Butterworth can be seen in
[vsnet-campaign-data 35]. A fading trend has been observed since August 5
(vsnet-campaign-dn 102).
Time-series observations are strongly encouraged.
Delta Sco (RA = 16h00m19s.9, Dec = -22d37'17")
Gradual fading trend can be seen in recent observations
(vsnet-campaign-be 34).
SN 2000cx (RA = 01h24m46s.15, Dec = +09o30'30".9)
The fading trend continues (vsnet-campaign-sn 42, 45, 46).
CI Aql (RA = 18h52m03s.6, Dec = -01d28m38.9s)
The fading have stopped since the early August. The current magnitude
is about 13.6mag (vsnet-campaign-nova 79).
The observations including eclipses are very useful to study this
recurrent nova.
V803 Cen (RA = 13h23m44s.5, Dec = -41d44'30".1)
Another outburst was reported on August 7 at 13.7mag (P. Williams)
(vsnet-campaign-dn 100). The object faded again on August 9
(vsnet-campaign-dn 104).
Close monitorings and time-series observations are encouraged.
XTE J1118+480 (RA = 11h18m10s.9, Dec = +48d02'12".9)
From the observation at Kyoto, M. Uemura reported that the rapid decline
trend apparently continued till August 5, but, the data on August 6 and 10,
which was observed under bad weather, suggested that this decline trend
seems to be stopped (vsnet-campaign-xray 36).
The confirmation of the current magnitude is urgently needed.
V1494 Aql (RA = 19h23m05s.4, Dec = +04d57'20".1)
The nightly averaged data observed by L. Cook can be seen in
[vsnet-campaign-nova 78].
*** Future schedule ***
V382 Vel, V1494 Aql, Nova in LMC 2000 campaign
(August 7) (August 21)
S. Starrfield and his collaborators will be obtaining CHANDRA
observations of V382 Vel and V1494 Aql the week beginning August 7, 2000
and they will be obtaining HST/STIS observations of Nova LMC 2000 the
week of August 21, 2000. Ground based observations are encouraged.
Observers those who are interested in this campaign, should contact
with Dr. Starrfield (sumner.starrfield@asu.edu).
[vsnet-campaign-nova 71]
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 368].....
"The V446 Her campaign from July 7 was started (through the end of
September). But we have received very few observations since then.
Negative observations, for instance, <17.0, are also useful.
We strongly encourage observers to contribute to this project.
Let's clarify the physics of post novae!"
*** General information ***
V1504 Cyg
light curve sent by E. Pavlenko:
http://ftp.kusastro.kyoto-u.ac.jp/pub/vsnet/DNe/V1504_Cyg/1504.eps
[vsnet-campaign 420]
FBS 2351+228 = NSV 26158
Picture and Spectrum by O. Trondal:
http://vsnet.geocities.com/SiliconValley/Garage/9531/nsv26185.htm
[vsnet-campaign 424]
(This summary is reproduction free.)
Regards,
Makoto Uemura
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VSNET Home Page: http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/
=============================================================================
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