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*** News from VSNET ***
The nova-like variable MV Lyr is now very bright.
A superoutburst of TV Crv is ongoing.
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 May 19, 2003, as VSNET campaign
circulation 1390
[Note a large part of detailed information is posted to vsnet-campaign
sub-lists].
VSNET Weekly Campaign Summary
*** Last week news ***
(new targets)
CH Her (RA = 18h34m46s.21, Dec = +24d47'57".0)
G. Poyner reported an outburst of CH Her on May 11 and 12. This
is one of rare outbursts in the last two years, and would be a
target of opportunity (vsnet-campaign-dn 3660).
HadV100 (RA = 18h19m05s.76, Dec = -30d19'06".7)
It is reported to be a large-amplitude Mira, which is supported in
the ASAS-3 data (vsnet-campaign-unknown 200, 201, 202, 203, 204).
TmzV772 (RA = 12h45m06s.82, Dec = +21d39'33".4)
C. Lloyd and S. Otero call for observations of the new eclipsing
variable, TmzV772. The period is proposed to be 1.03, 1.43, and
0.89 d, and C. Lloyd reported that the 0.89-d period is most likely
(vsnet-campaign-eclipse 66, 67, 68, 69, 70).
AI CMi (RA = 07h35m41s.2, Dec = +00d14'58")
S. Otero reported that ASAS-3 data brings a confirmation of his
observation of the post-AGB star AI CMi in a very bright maximum:
It was at V= 7.86 on May 10 (vsnet-campaign-mira 60). T. Kato
commented that AI CMi is suggested to have an evolutionary stage
close to proto-planetary nebulae (PPN). If this is the case, the
bolometric luminosity of such an object is close to its maximum in
its entire lifetime. It is thus noteworthy that if a real
"brightening" occurs in addition to its baseline luminosity. It
could be one of brightest pulsation maxima, but there may be a
possibility that a more dramatic change (such as rho Cas
mass-ejection episode) may be taking place (vsnet-campaign-mira 61).
SN 2003eg (RA = 12h50m58s.33, Dec = -14d20'01".1)
SN 2003eg is hosted by NGC 4727, a spiral galaxy making a close
pair with NGC 4724. There are many galaxies having v_r ~ 4000 km/s
in 30' of NGC 4727. Though the recession velocity of NGC 4727
itself is tabulated as 7622 km/s, it seems to have a same distance
as the surrounding galaxies; it is supported the brightest observed
magnitude of SN (type unknown) 1965B also produced by NGC 4727 was B
= 16.0. The expected maximum for typical SN Ia in this group is mag
about 15.5. The spectral classification of the SN and the
determination of the recession velocity is important
(vsnet-campaign-sn 622).
SN 2003eh (RA = 11h08m24s.34, Dec = +03d29'47".0)
SN 2003eh is hosted by MCG +01-29-3, a barred-spiral galaxy. The
expected maximum for typical SN Ia is mag about 16.7
(vsnet-campaign-sn 622).
(continuous targets)
TV Crv (RA = 12h20m23s.56, Dec = -18d27'02".7)
The superoutburst is still ongoing (vsnet-campaign-dn 3665, 3670).
In the light curve obtained by P. Nelson on May 18, superhumps still
persists with a full amplitude of 0.15 mag (vsnet-campaign-dn 3669).
RX Vol (RA = 08h39m32s.30, Dec = -66d17'39".2)
The data taken by B. Monard clearly indicate that the object was
just undergoing a "rebrightening phase" during the terminal portion
of a superoutburst plateau on late May 12. This feature is
associated with systems with short orbital periods and high outburst
amplitudes (the best example being V1028 Cyg) (vsnet-campaign-dn
3661). An analysis of the data until May 12 indicates overall
positive period derivative feature (around dot(P)/P = +7*10^(-5)).
This is very consistent with the superhump behavior of the SU UMa
stars at this superhump period (vsnet-campaign-dn 3662).
OU Vir (RA = 14h35m00s.14, Dec = -00d46'07".0)
The superhumps have become less prominent. A preliminary analysis
of the entire data more strongly suggests the presence of a general
period decrease. On May 9-10, post-eclipse "dip"-like phenomenon
was observed superimposed on superhump maxima (vsnet-campaign-dn
3663). The object has entered a rapid fading phase from the
superoutburst on May 18 (vsnet-campaign-dn 3665, 3666). During this
phase, the eclipses observed by T. Krajci are sharp and deep (1.5
mag). Outside the eclipses, the light curve looks like undulations.
It may have been possible that the superhumps are beginning to lose
its coherence (vsnet-campaign-dn 3667).
SN 2003dh (RA = 10h44m50s.030, Dec = +21d31'18".15)
The Subaru team observed SN 2003dh, a supernova component of
GRB030329 spectropolarimetrically and spectroscopically (May 8.3 and
9.3 UT). It closely resembles that of SN 1997ef (type-Ic hypernova)
about 40 days after explosion, which is comparable to the rest-frame
age of SN 2003dh (34-35 days). (IAUC 8133)(vsnet-campaign-sn 621).
V445 Pup (RA = 07h37m56s.88, Dec = -25d56'59".1)
S. Otero reported that ASAS-3 data provide pre-discovery
observations of V445 Pup. It reveals that V445 Pup had already been
bright on 2000 November 20, and experienced a maximum at V=8.46 on
November 30 (vsnet-campaign-nova 1253, 1254).
V4745 Sgr (RA = 18h40m02s.54, Dec = -33d26'55".1)
The rebrightening was terminated, and then the object started
rapid fading again (vsnet-campaign-nova 1249, 1250, 1255, 1256).
V4743 Sgr (RA = 19h01m09s.38, Dec = -22d00'06".2)
Reported observations show possible oscillations having a 30-d
periodicity. The nova may be experiencing some sort of "transition
phase" activity. If it is the case, the analogy with V1494 Aql may
be more strengthened. However, the ASAS-3 data show a smoother
decline with little fluctuation (vsnet-campaign-nova 1252).
AH Her (RA = 16h44m09s.99, Dec = +25d15'02".1)
A possible fading from a standstill was reported
(vsnet-campaign-dn 3659).
MV Lyr (RA = 19h07m15s.93, Dec = +44d01'10".7)
Some observations show that it is now very bright at
12.1-12.3mag. The current brightness surpasses the recorded
magnitudes at least since 1994 (vsnet-campaign-nl 117).
GY Cnc (RA = 09h09m50s.5, Dec = +18d49'47")
The eclipsing dwarf nova, GY Cnc experienced an outburst on May 13
and 14, as reported by E. Muyllaert and M. Simonsen
(vsnet-campaign-dn 3364).
*** Future schedule ***
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 ***
OU Vir
Eclipse ephemeris, see [vsnet-campaign-dn 3658, 3668]
TmzV772
CCDV chart and phase plots at:
http://members.aol.com/dwest61506/page39.html
Visual chart:
http://members.aol.com/dwest61506/page40.html
Reversed Visual Chart:
http://members.aol.com/dwest61506/page65.html
Eclipse ephemeris, see [vsnet-campaign-ecl 66, 69]
AI CMi
Light curve provided by S. Otero:
http://ar.geocities.com/varsao/Curva_AI_CMi.htm
[vsnet-campaign-mira 60]
(This summary can be cited.)
Regards,
Makoto Uemura
Return to the Powerful Daisaku Nogami
vsnet-adm@kusastro.kyoto-u.ac.jp
