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*** News from VSNET ***
Clear superhumps were detected in PU CMa. The superoutburst entered a
rapid fading phase.
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 June 2, 2003, as VSNET campaign
circulation 1394
[Note a large part of detailed information is posted to vsnet-campaign
sub-lists].
VSNET Weekly Campaign Summary
*** Last week news ***
(new targets)
4U 1630-47 (RA = 16h34m00s.4, Dec = -47d23'23")
According to ATEL #161, the black hole candidate X-ray transient
4U 1630-47 is undergoing an extended X-ray outburst (duration
nearly 260 d). There have been occasions of increased X-ray
activities recently (vsnet-campaign-xray 241).
MM Sco (RA = 17h30m45s.68, Dec = -42d11'09".2)
As reported by R. Stubbings on May 26, the SU UMa-type dwarf nova
MM Sco experienced an outburst (14.0-13.9mag) (vsnet-campaign-dn
3692). In the light curve obtained by B. Heathcote, the object was
fading at a rate of 0.5 mag/d on May 27. There was an indication of
0.05 mag variations, which may be either related to orbital or
superhump-type modulation. Although the observation does not
exclude the possibility of the early stage of a superoutburst, the
fainter magnitude than in the past superoutbursts makes it more
likely a normal outburst (vsnet-campaign-dn 3698, 3701, 3707, 3712).
V589 Her (RA = 16h22m07s.19, Dec = +19d22'36".3)
An outburst of the SU UMa-type dwarf nova V589 Her was reported on
May 27, but it was not confirmed by the observations by the Kyoto
team (vsnet-campaign-dn 3694, 3697). It was fainter than 16.2mag on
May 27, as reported by O. Trondal (vsnet-campaign-dn 3705).
SN 2003em (RA = 02h09m20s.23, Dec = -23d24'53".0)
SN 2003em is hosted by ESO 478-G6, an inclined spiral galaxy. It
is superimposed on the outer arm region. The expected maximum for
typical SN Ia is mag about 16.0 (vsnet-campaign-sn 628).
RS Oph (RA = 17h50m13s.56, Dec = -06d42'30".6)
RS Oph has been reported to be slightly brighter than normal. It
may be a sign of a new outburst (vsnet-campaign-nova 1261, 1264,
1265, 1274).
V1362 Cyg (RA = 20h03m41s.6, Dec = +36d25'32")
A brightening of V1362 Cyg was reported on May 29, but it has not
been confirmed (vsnet-campaign-be 240, 241, 242, vsnet-campaign-sdor
42, 43, 44).
V2335 Oph (RA = 18h04m17s.3, Dec = +04d43'44")
T. Kato reported, according to ASAS-3 CV alert, V2335 Oph may be
in outburst (mag 14.4). K. Torii, however, reported that it is not
in outburst. The ASAS-3 detection may have been a noise
(vsnet-campaign-dn 3714, 3718).
V405 Vul (RA = 19h53m05s.0, Dec = +21d14'50")
T. Kato reported, according to ASAS-3 CV alert, V405 Vul may be in
outburst (mag 13.8). K. Torii, however, reported that it is not in
outburst. The ASAS-3 detection may have been a noise
(vsnet-campaign-dn 3715, 3719).
SDSS J132723.39+652854.2
(RA = 13h27m23s.39, Dec = +65d28'54".2)
According to astro-ph/0305607 (Wolfe et al.), the SDSS cataclysmic
variable SDSS J132723.39+652854.2 is found to be an eclipsing
novalike system with a period of 3.28 hr. The object is suggested
to be an SW Sex type object. The magnitude is about 18
(vsnet-campaign-nl 121).
(continuous targets)
V660 Her (RA = 17h42m07s.3, Dec = +23d47'37".3)
The outburst faded (vsnet-campaign-dn 3703).
rho Cas (RA = 23h54m22s.99, Dec = +57d29'58".7)
In the spectrum taken by M. Fujii, the H-alpha line was seen in
absorption, but may be partly filled with an emission-line component
(vsnet-campaign-rhocas 17).
PU CMa (RA = 06h40m47s.67, Dec = -24d23'14".6)
In the light curves on May 26-27 taken by B. Monard and on May 25
by P. Nelson, the object clearly showed superhumps. These
observations finally (most probably) confirmed the SU UMa-type nature
of PU CMa (vsnet-campaign-dn 3695). The superhump period was
calculated to be 0.05789(2) d using all data sets reported upto May
29. This period is 2.1% longer than the orbital period
(vsnet-campaign-dn 3696, 3704, 3706, 3708). T. Kato reported a
superhump period derivative to be dot(P)/P = -3x10^(-5). Excluding
the slight anomaly of O-C on May 25 has yielded -1x10^(-5). In
either cases, the absolute value of dot(P)/P is small. Furthermore,
the period derivative seems to be slightly negative (period is
decreasing), which is a rather anomalous feature for a system with
this short superhump period (vsnet-campaign-dn 3711, 3713). The
star entered the rapid decline phase on May 30, and faded by 2 mag
on May 31. However, the superhumps (late superhumps?) still
prominently persist even on June 1 in the light curve taken by
B. Monard (vsnet-campaign-dn 3693, 3700, 3709, 3717, 3720).
delta Sco (RA = 16h00m19s.9, Dec = -22d37'17")
The object is gradually fading from the recent very bright state
(vsnet-campaign-be 238). In the spectrum taken by M. Fujii, the
Balmer lines are still in emission (vsnet-campaign-be 239).
V729 Sgr (RA = 19h16m49s.15, Dec = -26d14'33".2)
The object faded from the recent outburst (vsnet-campaign-dn 3716).
CR Boo (RA = 13h48m55s.42, Dec = +07d57'30".3)
A new outburst started on May 24 (vsnet-campaign-dn 3702).
OU Vir (RA = 14h35m00s.14, Dec = -00d46'07".0)
The Kyoto team detected a possible, post-superoutburst
rebrightening on May 29 (vsnet-campaign-dn 3710).
V4745 Sgr (RA = 18h40m02s.54, Dec = -33d26'55".1)
The nova experienced a new bright maximum around May 29
(vsnet-campaign-nova 1260, 1262). In the spectrum taken by
M. Fujii, the Fe II lines still persist, indicating the slow
evolution. The [O I] line at 8446 A has become slightly stronger
(vsnet-campaign-nova 1263).
MV Lyr (RA = 19h07m15s.93, Dec = +44d01'10".7)
The recent time-series observations confirm the presence of
large-amplitude (0.1-0.2 mag) strong spike-like quasi-periodic
features (typical time-scales 10-30 min), which remind us of V592
Cas, RX J1643.7+3402. It may be possible that this signal became
stronger as the system brightened to the current exceptional level.
There may be a undelying superhump signal, which needs to be
verified by further analysis and observations (vsnet-campaign-nl 122).
eta Car (RA = 10h45m03s.65, Dec = -59d41'03".7)
Recent reported observations can be seen in [vsnet-campaign-sdor
40, 41].
EE Cep (RA = 22h09m22s.8, Dec = +55d45'24")
The object is now in an eclipse (vsnet-campaign-ecl 77).
V504 Cen (RA = 14h12m49s.11, Dec = -40d21'37".1)
T. Kato reported that the object is a new, firmly established VY
Scl-type star. The rare brightness (mag about 13) makes it a very
ideal target for southern time-series observations
(vsnet-campaign-nl 123).
*** Future schedule ***
Multiwavelength AGN Surveys
a "Guillermo Haro" Astrophysics Conference
organized by INAOE
December 8-12, 2003
Cozumel, Mexico
http://vsnet.inaoep.mx/~agn2003/
[vsnet-campaign-agn 4]
IM Nor Campaign
by I. Hachisu (University of Tokyo) and the VSNET team
For more information, see [vsnet-campaign-nova 1241]
GRB Mini-Symposium in JENAM2003
For more information, http://vsnet.konkoly.hu/jenam03/
[vsnet-campaign-grb 31]
IAU JD17 "ATOMIC DATA FOR X-RAY ASTRONOMY"
ON JULY 22-23, 2003 at the XXVth IAU GENERAL ASSEMBLY
SYDNEY, AUSTRALIA, JULY 13-26, 2003
for more information:
http://vsnet.astronomy.ohio-state.edu/~pradhan/Iau/iau.html
[vsnet-campaign-xray 227]
"X-ray and Radio Emission of Young Stars"
July 28 - 29, 2003, Rikkyo University, Tokyo, Japan
for more information , please contact to kitamoto@rikkyo.ne.jp
[vsnet-campaign-xray 218]
Conference: THE INTERPLAY AMONG BLACK HOLES, STARS AND ISM IN
GALACTIC NUCLEI
in Gramado, south of Brasil, March 1-5, 2004
for more information, please contact to BHSIGN@if.ufrgs.br
[vsnet-campaign-agn 3]
eta Car: The next "shell event"/X-ray eclipse
M. Corcoran reported the event will occur this summer.
Coordinated ground-based observations of eta car along with the
X-ray observations would be really important.
For more information:
Latest X-ray light curve:
http://lheawww.gsfc.nasa.gov/users/corcoran/eta_car/etacar_rxte_lightcurve/
[vsnet-campaign-sdor 23, 24,
25, 26, 28, 29]
[vsnet-campaign-xray 172]
Light curve provided by S. Otero:
http://ar.geocities.com/varsao/Curva_Eta_Carinae.htm
[vsnet-campaign-sdor 22, 32, 33]
The 2003 Gamma Ray Burst conference
Hosted by Los Alamos,
in Santa Fe, New Mexico (USA), between September 8 and 12, 2003
http://grb2003.lanl.gov/
[vsnet-campaign-grb 13]
*** General information ***
PU CMa
VSNET page:
http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/DNe/pucma.html
[vsnet-campaign-dn 3699]
Image by P. Nelson:
http://vsnet.kusastro.kyoto-u.ac.jp/pub/vsnet/DNe/PU_CMa/nel1.jpg
[vsnet-campaign-dn 3706]
rho Cas
Spectrum taken by M. Fujii:
http://vsnet1.harenet.ne.jp/~aikow/rho_cas_20030528.gif
[vsnet-campaign-rhocas 17]
delta Sco
Spectrum taken by M. Fujii:
http://vsnet1.harenet.ne.jp/~aikow/delt_sco_20030528.gif
[vsnet-campaign-be 239]
V4745 Sgr
Spectrum taken by M. Fujii:
http://vsnet1.harenet.ne.jp/~aikow/v4745_sgr_20030528.gif
[vsnet-campaign-nova 1263]
Discussion about RS Oph, its neighbor comparison star, and recurrent
novae, see [vsnet-campaign-nova 1266, 1267, 1268, 1269, 1270,
1271, 1272, 1273]
MV Lyr
Article for the Czech publication Perseus in 1999 written by
L. Cook:
http://vsnet.geocities.com/lcoo/mvly1999.htm
[vsnet-campaign-nl 124]
(This summary can be cited.)
Regards,
Makoto Uemura
Return to the Powerful Daisaku
vsnet-adm@kusastro.kyoto-u.ac.jp
