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[vsnet-campaign-news 95] News from VSNET 66
*** News from VSNET ***
The historical outburst of WZ Sge is ongoing. Profiles of early
superhumps have become irregular, but ordinal superhumps are still
not seen.
For more detail information about these objects,
see below, "VSNET Weekly Campaign Summary" of the last week.
# This week's summary is delivered two days earlier since
# the author will be out of the office on the next Monday.
---------------------------------------------------------------------------
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 August 4, 2001, as VSNET campaign circulation 1063
[Note a large part of detailed information is posted to vsnet-campaign
sub-lists].
VSNET Weekly Campaign Summary
# This week's summary is delivered two days earlier since
# the author will be out of the office on the next Monday.
*** Last week news ***
(new targets)
J1628-41 (RA = 16h28m47s.267, Dec = -41d52'38".6)
G. Tsarevsky reported the discovery of a candidate of microquasars,
J1628-41 in [vsnet-campaign 1058]. The object shows a hard spectrum
in X-ray, a flat radio spectrum, and a K5 star-like spectrum in optical.
These imply that this object is a candidate of microquasars. They call
for observations on this object (vsnet-campaign-xray 78).
KL Dra (RA = 19h24m38s.14, Dec = +59d41'47".1)
M. Wood reported that they found KL Dra in high state (~16.7mag)
and observed superhumps with a period of 25 minutes (1527 s), which
is remarkably close to the 1490s period for CR Boo. They also
noted that the star was originally thought to be a supernova, and
it's original designations was sn1998di, however a spectrum showed
it to be similar to the AM CVn class of stars (vsnet-campaign 1050).
TU Men (RA = 04h41m38s.10, Dec = -76d36'09".7)
P. Nelson reported a possible outburst (12.2:mag) of TU Men
on July 30. B. Monard confirmed the outburst at 12.4 mag on
August 1 (vsnet-campaign-dn 1085).
(continuous targets)
WZ Sge (RA = 20h07m36s.53, Dec = +17d42'15".3)
The historical outburst is now ongoing (vsnet-campaign-dn 1063,
1071, 1091). The current magnitude is about 9.7mag (vsnet-campaign-dn
1091, 1098).
Since July 30, the profile of main humps has become broader and
the secondary hump tends to become stronger (vsnet-campaign-dn 1057,
1078). The amplitude of the main peak has become smaller from 0.5mag
to 0.2 - 0.1mag (vsnet-campaign-dn 1065). The hump profiles have
become irregular with time (vsnet-campaign 1060). Around August 2,
the decline speed has become slower (vsnet-campaign-dn 1080).
G. Masi reported eclipses occurring about 10 minutes early than
previsions from the ephemeris (vsnet-campaign-dn 1078).
The period analysis of humps shows possible variation of period,
however the ordinal superhumps are not apparently seen: G. Masi
reported a period of 0.05682 d which is longer than orbital one
(0.05668d) using his July 31 data (vsnet-campaign-dn 1065, 1066).
T. Kato however obtained a period near orbital period using the
combined data and further reported that the hump period may decrease
with time on the basis of daily averaged profiles (vsnet-campaign-dn
1067). T. Kato then reported a longer period of 0.05677 d using the
combined data of the later half on August 1 (vsnet-campaign 1052,
1053). He reported 0.05615 d using August 2 data and 0.056743 d
using August 1.5-2.5 data (vsnet-campaign 1054, vsnet-campaign-dn 1084).
The data set on August 2.1-3.1 shows 0.056596 d periodicity, which
implies the tendency of a shorter period (vsnet-campaign 1087, 1089).
On August 3, T. Kato reported the hump period is consistent with
the orbital one (vsnet-campaign 1061). Using the data from August
3.88 to 4.06, G. Masi reported a shorter period of 0.05659 d
(vsnet-campaign-dn 1093). T. Kato reported 0.056769 d using the data
on August 3.2-4.1 (vsnet-campaign 1062). G. Masi reported 0.057229 d
using his 6.5 hours run on August 3 (vsnet-campaign-dn 1094, 1096).
T. Kato obtained 0.05655 d using the same data (vsnet-campaign-dn 1097).
Time-series photometry by S. Kiyota on July 30 can be available
in [vsnet-campaign-data 68]. L. Kral reported photometry data by
M. Kolasa, T. Hynek, and L. Kral in [vsnet-campaign-data 69] and
[vsnet-campaign-data 70]. The VSNET collaboration team has obtained
a number of data sets which kindly sent by G. Masi and F. Mallia
(vsnet-campaign-dn 1058, 1065, 1083, 1090, 1100, 1102, 1103,
vsnet-campaign 1057), M. Richmond (vsnet-campaign-dn 1069, 1082, 1101),
L. Kral (vsnet-campaign-data 69, vsnet-campaign 1049), R. Novak
(vsnet-campaign-dn 1073), J. Pietz, L. Cook, D. Starkey, S. Kiyota,
B. Martin, A. Oksanen, M. Moilanen, A. Good, M. Kolasa, T. Hynek.
IX Dra (RA = 18h12m32s.2, Dec = +67d04'41")
As reported by M. Reszelski in August 1, IX Dra experienced an
outburst at 14.6mag (vsnet-campaign-dn 1079).
IP Peg (RA = 23h23m08s.7, Dec = +18d24'59".1)
The outburst is gradually fading. The current magnitude is
13.2-13.5 (vsnet-campaign-dn 1064, 1072, 1092).
V2274 Cyg (RA = 20h07m17s.94, Dec = +36d04'37".2)
As reported since July 31, this nova has rebrightened
(vsnet-campaign-nova 422, 423). The time-series photometry
by K. Hornoch can be available in [vsnet-campaign-data 71].
V818 Sco (RA = 16h19m55s.07, Dec = -15d38'24".5)
The strong activity still continues around 12.0-12.7mag
(vsnet-campaign-xray 79).
V1504 Cyg (RA = 19h28m55.87s, Dec = +43d05'39".9)
The superoutburst still continues. The current magnitude seems
to be fainter than 15mag (vsnet-campaign-dn 1062, 1077).
BL Lac (RA = 22h02m42.86s, Dec = +42d16'37.6")
The fading continues. The current magnitude is about 14.7mag
(vsnet-campaign-blazar 219).
FO And (RA = 01h15m32s.14, Dec = +37d37'35".5)
The superoutburst detected in July 10 is still ongoing
(vsnet-campaign-dn 1081).
V445 Pup (RA = 07h37m56s.88, Dec = -25d56'59".1)
B. Monard reported a dramatically fading of V445 Pup.
It seems to be fainter than 12.9mag on August 1 although it was
reported to be 11.5mag on July 11 (vsnet-campaign-nova 424).
*** Future schedule ***
AM Her and VY Scl stars campaign with the Keck I telescope
from August 12-14
F. Rinwald wrote in [vsnet-campaign 1059]:
"Many cataclysmic variables, especially AM Her and VY Scl stars, have
erratic and poorly understood low states. We have an observing run
scheduled on the Keck I telescope from August 12-14, to find out why. It
has long been suspected that these low states may be due to starspots on
the mass-losing star that form or move over L1 and choke off the flow.
This idea is not without problems, however, but then that's why we want to
get our spectra."
They call for photometric monitorings and listed targets in
[vsnet-campaign 1059] and [vsnet-campaign-nl 23].
WZ Sge campaign
D. Steeghs wrote:
"Several of us are organizing a campaign on the current outburst
of WZ Sge, using a large variety of ground based facilities as well as
space observatories. A web-page has been setup listing the scheduled
observations so far which we intend to keep up to date at:
http://vsnet.astro.soton.ac.uk/~ds/wzsge.html
"
For more information, see [vsnet-campaign 1039]
V446 Her campaign until September
conducted by Matthias Schreiber, Boris Gaensicke, and Daisaku Nogami
For more detailed information, see [vsnet-campaign-dn 918],
[vsnet-campaign-nova 349], or [vsnet-campaign 983]
CV conference at Goettingen, 5-10 August 2001
[vsnet-announce 15, 20]
Two Years of Science with Chandra *
* This meeting will also be the 12th Annual Maryland Astrophysics
Conference
September 5-7, 2001
For more information, see [vsnet-campaign-xray 66]
*** General information ***
WZ Sge
Light curve obtained by the VSNET collaboration team:
http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/DNe/wzsge01.html
[vsnet-campaign-dn 1055, 1056, 1059,
1060, 1061, 1070, 1074, 1075,
1088, 1095
vsnet-campaign 1055]
Light curves presented by G. Masi:
http://vsnet.eurolink.it/comets/wzsge.htm
[vsnet-campaign-dn 1078, 1086, 1094]
Light curve and data set by M. Richmond:
http://spiff.rit.edu/richmond/ritobs/jul31_2001/jul31_2001.html
[vsnet-campaign-dn 1069]
http://spiff.rit.edu/richmond/ritobs/aug01_2001/aug01_2001.html
[vsnet-campaign-dn 1082]
Light curves presented by L. Kral
http://vsnet.sin.cvut.cz/~lkral/wzsge/wzen.htm
[vsnet-campaign 1049]
eclipse ephemeris, see [vsnet-campaign-dn 1076]
KL Dra
Light curve in high state presented by M. Wood:
http://vsnet.astro.fit.edu/wood
[vsnet-campaign 1050]
VSNET page:
http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/DNe/sn1998di.html
[vsnet-campaign 1051]
V1178 Sco
preprint by T. Kato:
article, see [vsnet-campaign-nova 425]
figures:
http://ftp.kusastro.kyoto-u.ac.jp/pub/vsnet/preprints/V1178_Sco/
(This summary can be cited.)
Regards,
Makoto Uemura
vsnet-adm@kusastro.kyoto-u.ac.jp
Return to Daisaku Nogami
vsnet-adm@kusastro.kyoto-u.ac.jp
VSNET Home Page