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[vsnet-campaign-news 180] News from VSNET
*** News from VSNET ***
V. Tabur discovered a possible nova (red mag 9.7) in Sagittarius on
CCD images taken on October 25.
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 October 28, 2002, as VSNET campaign
circulation 1345
[Note a large part of detailed information is posted to vsnet-campaign
sub-lists].
VSNET Weekly Campaign Summary
*** Last week news ***
(new targets)
Nova in Sgr No. 4 (RA = 17h47m21s.74, Dec = -23d28'23".1)
A possible nova (red mag 9.7) in Sagittarius was discovered by
V. Tabur on CCD images taken on October 25. W. Liller confirmed it
to be V=9.98 on October 27 (vsnet-campaign-nova 1117, 1118). No
variable star at this location has been reported by OGLE II team.
Together with the lack of a bright 2MASS counterpart, the object is
most likely a nova (vsnet-campaign-nova 1119). Multi-color
observations by S. Kiyota shows that the possible nova seems to be
relatively reddened (vsnet-campaign-nova 1121). G. Masi reported a
candidate of its quiescent counterpart of a USNO star with r=16.1
(vsnet-campaign-nova 1122).
V697 Sco (RA = 17h51m21s.83, Dec = -37d24'55".2)
V697 Sco (Nova Sco 1941) has been proposed to be an intermediate
polar (IP) by B. Warner and P. A. Woudt in astro-ph/0210458.
T. Kato commented that this nova did not show apparent oscillations
(vsnet-campaign-nova 1108). On the other hand, A. Retter commented
that observations of this nova were too scarce to determine whether
the oscillation phase was present (vsnet-campaign-nova 1109).
HP Lyr (RA = 19h21m39s.12, Dec = +39d56'09".0)
D. Graczyk et al. proposed in astro-ph/0210448 that HP Lyr is
possibly the hottest RV Tau type object. HP Lyr was previously
recognized as an eclipsing binary (vsnet-campaign-rvtau 4).
SN 2002ha (RA = 20h47m18s.58, Dec = +00d18'45".6)
The host galaxy of SN 2002ha is NGC 6962, a spiral galaxy making a
pair with NGC 6964 and making a group with several other galaxies.
The expected maximum for typical SN Ia is mag about 15.5
(vsnet-campaign-sn 484, 485). According to IAUC 7999, a spectrum
taken on Oct 25.03 shows that it is type Ia SN about 3 days before
maximum with interstellar extinction in the host galaxy. Note that
this SN was not detected 6 days before spectroscopy, which is
unusual for typical SN Ia (vsnet-campaign-sn 486).
SW UMa (RA = 08h36m42s.80, Dec = +53d28'38".2)
P. Schmeer and E. Muyllaert reported an outburst of SW UMa on
October 24 (vsnet-campaign-dn 2915, 2916, 2917, 2920). T. Kato
reported the appearance of 0.1-mag likely superhump-type features
during a rising phase observed by K. Tanabe on October 24
(vsnet-campaign-dn 2924, 2927). The superhumps were growing on
Oct. 24, and reached an amplitude of 0.1 mag on Oct. 25. Short-term
(minutes) modulations are superimposed, which may be QPOs
(super-QPOs) (vsnet-campaign-dn 2929). The superoutburst is now
ongoing (vsnet-campaign-dn 2922, 2932).
V844 Her (RA = 16h25m01s.69, Dec = +39d09'25".9)
The short-period SU UMa-type (superhump period 0.05592 d) dwarf
nova V844 Her experienced an relatively rare outburst as reported by
E. Muyllaert, P. Schmeer and H. McGee on October 23. The all
recorded outbursts of V844 Her have been superoutbursts. The last
superoutburst was in 2002 May. The interval of the outbursts has
become shorter than the previous values (vsnet-campaign-dn 2914).
In the light curve taken by K. Tanabe on October 24, there is no
strong superhump signal, indicating that the present outburst is a
normal outburst (vsnet-campaign-dn 2923). The object then quickly
faded (vsnet-campaign-dn 2918, 2920, 2926, 2925, 2931, 2933).
MisV1181 (RA = 22h58m09s.12, Dec = +66d21'12".4)
The MISAO team discovered a possible nova or a new transient
object of 12.7mag on their CCD images taken in 2001 September 19.
Nothing appears at this position on any Palomar plates and DSS
images. Recent unfiltered CCD images taken by T. Muramatsu on
Oct. 25, 2002 also show it at about 20 mag (vsnet-campaign-nova
1120).
RX J1039.7-0507 (RA = 10h39m47s.2, Dec = -05d07'02")
According to astro-ph/0210565 (Woudt and Warner), RX J1039.7-0507
is confirmed to be a short-period (P=1.574 h) CV with a strong
reflection effect. Based on the existence of other periods, the
authors suggest that the object is likely an intermediate polar,
which may have been undergoing a recent nova eruption
(vsnet-campaign-ip 95).
(continuous targets)
IP Peg (RA = 23h23m08s.7, Dec = +18d24'59".1)
An outburst to 13.7mag was reported by M. Linnolt on October 24
(vsnet-campaign-dn 2919). Reported observations showed that the
outburst is a relatively faint one (vsnet-campaign-dn 2921, 2928,
2930).
Probable nova in SMC (RA = 00h56m30s.49, Dec = -72d36'29".1)
B. Monard performed astrometry and reported the above position.
He also reported the object at 13.8CR mag on October 20
(vsnet-campaign-nova 1107). W. Liller reported V(bb)=14.03 on
October 21, which implies that the time for the candidate to fade 2
magnitudes, t2, is approximately 6 days (vsnet-campaign-nova 1110).
He further commented that a nova scenario is entirely reasonable
based on the predicted maximum and quiescent magnitude estimated
from t2 (vsnet-campaign-nova 1111, 1112). The object is now fading
(vsnet-campaign-nova 1113).
GSC 6846:6 (RA 18h03m14s.47, Dec = -25d14'22".1)
D. West reported this new variable may have reached its maximum
during the last week (vsnet-campaign-unknown 119).
Var73 Dra (RA = 20h23m38s.193, Dec = +64h36m26s.91)
T. Kato performed period analysis and reported a revised superhump
period of 0.1051(2) d. This period would make Var73 Dra a "twin"
system with the NY Ser, an SU UMa-type dwarf nova in the period gap
(Nogami et al. (1998) 50, L1), although other aliases are still
possible (vsnet-campaign-dn 2909).
Z UMi (RA = 15h02m01s.35, Dec = +83d03'48".7)
Some observations indicate a fading to 11.6-11.7mag around October
20 (vsnet-campaign-rcb 80).
SN 2002gw (RA = 02h25m02s.97, Dec = -24d47'50".6)
According to IAUC 8001, spectra of SN 2002gw taken by S. Shectman
and M. Hamuy with Las Campanas 6.5-m telescopes on Oct. 24-25
revealed that it is type II SN with a high expansion velocity (9300
km/s) (vsnet-campaign-sn 487).
SN 2002gy (RA = 03h22m36s.45, Dec = +09d28'22".0)
According to IAUC 7999, its spectrum taken on Oct. 25.21 resembles
that of type Ib/c SN. It is heavily reddened also by the
interstellar matter within the host galaxy (vsnet-campaign-sn 486).
SN 2002ap (RA = 01h36m23s.85, Dec = +15d45'13".0)
The object is now at 17th mag (vsnet-campaign-sn2002ap 205).
V348 Sgr (RA = 18h40m19s.94, Dec = -22d54'29".1)
The object remained the bright state at around 12.2-12.4mag
(vsnet-campaign-rcb 81).
BL Lac (RA = 22h02m42s.86, Dec = +42d16'37".6)
The active state had continued, and on October 26-27, a major
flare to 12.9mag was reported (vsnet-campaign-blazar 278, 279, 280).
V4743 Sgr (RA = 19h01m09s.38, Dec = -22d00'06".2)
The fading rate became slower. The object have entered in 9th mag
(vsnet-campaign-nova 1098, 1114).
V4742 Sgr (RA = 18h02m21s.864, Dec = -25d20'32".22)
The fading still continues (vsnet-campaign-nova 1115).
V838 Mon (RA = 07h04m04s.816, Dec = -03d50'50".94)
In astro-ph/0210463, N. Soker and R. Tylenda proposed a new model
for the phenomena of V838 Mon, in which the observed features of
V838 Mon is interpreted with the merger of two main sequence stars
(vsnet-campaign-v838mon 394, 395, 396, 397, 398).
V854 Cen (RA = 14h34m49s.8, Dec = -39d33'18")
The object further faded to <9.0 mag, as reported by P. Williams
on October 16 (vsnet-campaign-rcb 78).
Possible Nova in M110
The object have rapidly faded (vsnet-campaign-nova 1116).
*** Future schedule ***
International Workshop -- Extremely High Energy Cosmic Rays --
November 5-6, 2002
at RIKEN (The Institute of Physics and Chemical Research), Japan
Suzuki Umetaro Hall (#52), South Area, Wako main campus
Contact to: workshop2002@euso.riken.go.jp
[vsnet-campaign-grb 8]
IAU Colloquium 194
"Compact Binaries in the Galaxy and Beyond"
17-22 November 2003, La Paz, Mexico
Contact Details
Web page: http://bufadora.astrosen.unam.mx/~iau194
Email: iau194@astrosen.unam.mx
[vsnet-campaign-sn 467]
[vsnet-campaign-xray 154]
Texas in Tuscany
XXI Symposium on Relativistic Astrophysics
Florence, Italy, December 9-13, 2002
For more information:
http://vsnet.arcetri.astro.it/~texaflor/
[vsnet-campaign-xray 142]
SUPERNOVAE (10 YEARS OF SN1993J)
22-26 April 2003, Valencia, Spain
Web site: http://vsnet.uv.es/2003supernovae/
[vsnet-campaign-sn 342]
[vsnet-campaign-sn 452]
*** General information ***
SN 2002ha
Discovery image:
http://astron.berkeley.edu/~bait/2002/sn2002ha.gif
[vsnet-campaign-sn 485]
IP Peg
Eclipse ephemeris, see [vsnet-campaign-dn 2919]
V838 Mon
Images of lightecho:
http://hometown.aol.com/dwest61506/page36.html
http://vsnet.tenagraobservatories.com/
[vsnet-campaign-v838mon 399]
(This summary can be cited.)
Regards,
Makoto Uemura
Return to Daisaku Nogami
vsnet-adm@kusastro.kyoto-u.ac.jp
VSNET Home Page