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[vsnet-campaign-news 99] News from VSNET 70
*** News from VSNET ***
The historical event of WZ Sge outburst is still ongoing.
The object currently experiences the seventh re-brightening.
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 September 3, 2001, as VSNET campaign circulation
1154
[Note a large part of detailed information is posted to vsnet-campaign
sub-lists].
VSNET Weekly Campaign Summary
*** Last week news ***
(new targets)
PY Per
As reported by M. Simonsen on August 29, the UGZ-type star
PY Per is in outburst at 14.1mag (vsnet-campaign-dn 1421).
V347 Pup
As reported by B. Monard, the object is now relatively bright
(12.8mag on August 29; vsnet-campaign-nl 26).
3C66A
The blazer 3C66A has recently been brighter than usual
(14.1mag on August 28; vsnet-campaign-blazar 222).
AS270
As reported by S. O'Connor, an outburst of 11.8mag of AS270
was detected on August 28 (vsnet-campaign 1146).
V844 Her
As reported by C. P. Jones on August 31, the SU UMa-type dwarf
nova V844 Her is undergoing a relatively rare outburst. The last
outburst occurred in 2000 July. The most unusual characters of
this dwarf nova is the apparent absence of normal outburst, while
the intervals of superoutbursts are not especially long
(vsnet-campaign 1148). The superoutburst is still ongoing.
The current magnitude is around 12.2mag (vsnet-campaign-dn 1476).
AQ Eri
As reported by P. A. Dubovsky on August 31, AQ Eri experiences
an outburst at 13.3mag (vsnet-campaign-dn 1451).
NGC 6440 X-ray transient (RA = 17h48m53s.4, Dec = -20d21'20")
According to ATEL No. 74, the X-ray transient in NGC 6440 is in
outburst (in't Zand et al.). The source has been confirmed to be
identified with the currently outbursting optical variable V2
(vsnet-campaign-xray 83, 84, vsnet-campaign 1151, 1152).
(continuous targets)
HO Del (RA = 20h36m55s.49, Dec = +14d03'09".4)
M. Moilanen performed time-series observations on August 29
and reported it was 14.3mag (vsnet-campaign-dn 1408). The
obtained light curve clearly showed superhumps with a period of
0.063262d (vsnet-campaign-dn 1419). The superoutburst is still
ongoing. It is now around 14mag (vsnet-campaign-dn 1413, 1426,
1439, 1452, 1465).
V4739 Sgr = Nova Sgr 2001 No. 2
(RA = 18h24m46s.04, -30d00'41".1)
B. Liller reported that no object was seen on August 18.04 and
a low-resolution spectrum with 0.20m telescope showed the H-alpha
emission (vsnet-campaign-nova 485). A. Pearce reported an early
observation of 8.9mag on August 28 (vsnet-campaign-nova 486).
M. Fujii performed spectroscopy and obtained a spectrum with H-alpha
(FWHM=4700km/s) and H-beta emission lines. He suggested that
this nova is a He/N-type nova and the spectrum is similar to
that of the reccurent nova, U Sco (vsnet-campaign-nova 487).
The object rapidly faded since around August 28 (vsnet-campaign-nova
488, 493). The decline speed became rather gradual on August 30
(vsnet-campaign-nova 497, 500), and then, again rapidly faded
on August 31 (vsnet-campaign-nova 502, 505). The current magnitude
is around 10.8mag (vsnet-campaign-nova 506).
KV And (RA = 02h17m13s.85, Dec = +40d41'30".6)
The superoutburst is still ongoing. It is now about 15mag
(vsnet-campaign-dn 1415, 1453).
SN 2001du (RA = 03h33m28s.7, Dec = -36d08'32")
It is gradually fading and the current magnitude is about 14.6
(vsnet-campaign-sn 232).
V630 Cyg (RA = 21h34m59s.21, Dec = +40d40'18".5)
The likely superoutburst continues at about 14.2mag
(vsnet-campaign-dn 1414, 1423, 1435, 1440, 1454).
V2275 Cyg = Nova Cyg 2002 No. 2
(RA = 21h03m02s.00, Dec = +48d45'52".9)
The smooth fading continues (vsnet-campaign-nova 489, 494, 496,
498, 501, 503, 505). M. Fujii performed spectroscopy on August 22
and reported that the Balmer lines became more intensive. The
FWHM of H-alpha is 3100km/s. Based on the clear presence of Fe II
multiplets, Fujii concluded that the nova is a typical "Fe II-type"
nova (vsnet-campaign-nova 490).
WZ Sge (RA = 20h07m36s.53, Dec = +17d42'15".3)
WZ Sge has still repeated re-brightenings (vsnet-campaign-dn 1411,
1412, 1422, 1425, 1434, 1438, 1464, 1475, vsnet-campaign 1149).
The extensive campaign is ongoing (vsnet-campaign-dn 1410, 1418,
1429, 1447, 1459, 1462, 1468, 1469, vsnet-campaign 1153).
The peak brightness of the fourth rebrightening may even surpass
those of the three preceding ones. The profile of humps became
a "triple wave" (vsnet-campaign 1145, vsnet-campaign-dn 1424).
The fourth rebrightening was terminated on August 28. During
its fading phase, J. Pietz reported short-term variations with
an amplitude of 0.1-0.15mag (vsnet-campaign-dn 1409) and eclipses
became sharper and deeper (vsnet-campaign-dn 1420). The QPOs
detected by M. Moilanen showed somewhat shorter period of 2-3min
than that observed in the previous one (vsnet-campaign-dn 1427).
At the bottom, the main hump was observed at phase 0.5 and shallow,
slightly broad, eclipses were also present (vsnet-campaign-dn 1431).
A rapid rising to the fifth rebrightening with 0.15mag/hr was
reported (vsnet-campaign-dn 1428, 1432, 1436, 1443). During this
phase, there were weak periodic signals. The strongest hump signal
resides just after the eclipse times. It may be that altough
superhumps may have newly grown (vsnet-campaign-dn 1433). At the
peak of the fifth rebrightening on August 30, the superhumps and
eclipses became weak (vsnet-campaign-dn 1444, 1446). The duration
of this peak of was a little longer (vsnet-campaign 1147), however
faded on August 31 when humps and eclipses were again strong
(vsnet-campaign 1150, vsnet-campaign-dn 1456).
The sixth rebrightening was reported on August 31/September 1
(vsnet-campaign-dn 1458, 1461, 1470). The clear appearance of
eclipses and humps at the sixth rebrightening maximum may suggest
the presence of a precessing component, which is eclipsed at certain
times (vsnet-campaign-dn 1460). The duration of the flat maximum
exceeds 0.5 d (vsnet-campaign 1154). The complicated "triple" humps
were observed (vsnet-campaign-dn 1463). The phase of eclipses
particularly changed to a great extent. At maximum, the phase tended
to be earlier than the predicted times. Later during the decline,
the eclipses became quite asymmetric (vsnet-campaign-dn 1466).
On September 2, the object faded from the sixth rebrightening.
The QPOs with 2-5min were detected (vsnet-campaign-dn 1472). The
"phase 0.6 dip" was also again observed (vsnet-campaign-dn 1474).
A new rebrightening was observed on September 2/3
(vsnet-campaign-dn 1473, 1477).
V1008 Her (RA = 18h05m46s.31, Dec = +31d40'18".1)
The long outburst had finally faded around August 27
(vsnet-campaign-dn 1441).
IX Dra (RA = 18h12m32s.2, Dec = +67d04'41")
The outburst continued at least until August 28 at 16.0mag
(vsnet-campaign-dn 1416).
V445 Pup
The object is now very faint (<14.1 on September 1;
vsnet-campaign-nova 492, 507).
V1548 Aql
R. J. Modic reported a new brightening of this nova from 14.4mag
on September 1 to 13.7 on September 2 (vsnet-campaign-nova 508).
*** Future schedule ***
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]
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 ***
V4739 Sgr
Discovery Story by A. Pereira, see [vsnet-campaign-nova 483].
Spectrum by M. Fujii:
http://vsnet1.harenet.ne.jp/~aikow/v4739_sgr.gif
[vsnet-campaign-nova 487]
Image by G. U. Nappi:
http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/Novae/nsgr01-2.html
[vsnet-campaign-nova 499]
WZ Sge
Nightly averaged magnitude, see [vsnet-campaign-dn 1417, 1430,
1445, 1457, 1467]
Light curve by T. Hynek:
http://vsnet.mujweb.cz/www/thynek/var/WZ_Sge_010824_k.jpg
http://vsnet.mujweb.cz/www/thynek/var/WZ_Sge_010814_s.jpg
[vsnet-campaign-data 82]
Light curve by T. Vanmunster:
http://vsnet.lunarpages.com/cbabelgium
[vsnet-campaign-dn 1424]
Light curve by D. Starkey:
http://vsnet2.fwi.com/~starkey/variable_stars.htm
[vsnet-campaign-dn 1432]
Time-series data by Rit team:
http://spiff.rit.edu/richmond/ritobs/aug29_2001/aug29_2001.html
[vsnet-campaign-dn 1437]
http://spiff.rit.edu/richmond/ritobs/aug30_2001/aug30_2001.html
[vsnet-campaign-dn 1450]
http://spiff.rit.edu/richmond/ritobs/sep02_2001/sep02_2001.html
[vsnet-campaign-dn 1471]
Sequence by A. Henden and A. Landolt, see [vsnet-campaign-dn 1442]
Chart by M. Richmond:
http://spiff.rit.edu/richmond/ritobs/wz_chart/landolt_chart.html
[vsnet-campaign-dn 1448]
V2275 Cyg
Multi color photometry by G. Sostero, see [vsnet-campaign-nova
495]
(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