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[vsnet-campaign-news 170] News from VSNET
*** News from VSNET ***
The SU UMa-type nature of AB Nor has been almost confirmed.
A rare superoutburst of KV Dra is now 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 September 2, 2002, as VSNET campaign
circulation 1334
[Note a large part of detailed information is posted to vsnet-campaign
sub-lists].
VSNET Weekly Campaign Summary
*** Last week news ***
(new targets)
AB Nor (RA = 15h49m16s, Dec = -43d04'51")
R. Stubbings detected an outburst (14.0mag) of this object on
August 31. AB Nor is most likely an SU UMa-type dwarf nova. The
last long outburst (presumably superoutburst) was observed in 2000
April, with a prominent precursor. The light curve obtained by
B. Monard shows possible modulations with amplitudes < 0.1mag
(vsnet-campaign-dn 2769, 2784). The data by P. Nelson confirmed
these growing humps. Using these data sets, T. Kato calculated the
best superhump period of 0.0826(10) d (vsnet-campaign-dn 2786).
These results almost confirmed the SU UMa-type nature of AB Nor.
The outburst is still ongoing (vsnet-campaign-dn 2770).
KV Dra (RA = 14h50m38.4s, Dec = +64d03m29s)
As M. Simonsen reported, the SU UMa-type dwarf nova KV Dra
(RX J1450.5+6403) was reported to be in outburst on August 31. The
object underwent an superoutburst in 2000 May (see vsnet-alert 4858
and Nogami et al. 2000 A&A 364, 701). However, only two normal
outbursts have been reported since then. The outburst frequency of
this object may be low (vsnet-campaign-dn 2767). The outburst was
promptly confirmed by K. Torii (vsnet-campaign-dn 2768). T. Kato
reported superhumps detected by A. Oksanen, J. Pietz, D. Starkey,
and L. Cook. The present outburst looks like a rare faint
superoutburst. In addition to the superhump variation, there are
short-term variations, which could be related to super-QPOs
(vsnet-campaign-dn 2777, 2778, 2785). The superoutburst is still
ongoing (vsnet-campaign-dn 2780).
TV Col (RA = 05h29m25s.5, Dec = -32d49'05".2)
As detected by R. Stubbings on September 1, the intermediate polar
TV Col is in outburst (11.9mag). The Kyoto team has took some
data. The outbursts of TV Col may be extremely short (hours)
(vsnet-campaign-ip 91).
Var73 Dra (RA = 20h23m38s.193, Dec = +64d36'26".91)
According to A&A 391, 565 (2002) Antipin and Pavlenkoi, Var73 Dra
is a long-period (Psh=0.0954 d) SU UMa-type dwarf nova. The light
curve of the outbursts strongly resembles those of a long-period
system NY Ser. Further observations are clearly strongly
encouraged (vsnet-campaign-dn 2761). B. Skiff reported the
Cambridge APM catalogue shows this star at outburst on the later of
the two overlapping POSS-I plates (epoch 1953.61;mb=15.8,mr=15.5,
epoch 1952.63;mb=19.4,mr=19.5)(vsnet-campaign-dn 2762).
SN 2002ep (RA = 21h57m21s.66, Dec = -07d51'24".8)
SN 2002ep was discovered by W. M. Wood-Vasey et al. from Palomar
NEAT images. It was 18.7mag on August 6.47. An apparent host
galaxy of SN 2002ep is 2MASXi J2157220-075125, which is possibly a
member of Abell 2399. The SN is located on 5"due west of the center
of the host galaxy. If the membership is correct, the expected
maximum for typical SN Ia is mag about 18.6 (vsnet-campaign-sn 466).
SN 2002eq (RA = 21h19m00s.19, Dec = -16d17'12".7)
SN 2002eq was discovered by W. M. Wood-Vasey et al. from Palomar
NEAT images. It was 19.6mag on August 8.36. An apparent host
galaxy of SN 2002eq is APMUKS(BJ) B211613.63-162951.1, which seems
to be a quite distant galaxy (vsnet-campaign-sn 466).
SN 2002er (RA = 17h11m29s.88, Dec = +07d59'44".8)
SN 2002er was discovered on LOTOSS KAIT images. It was about
17.5mag on August 23.2. The host galaxy of SN 2002er is UGC 10743
(offset is 12"W,5"N), a nearby spiral or lenticular galaxy somewhat
affected the Milky Way extinction. It seems to be a young SN in a
rising phase, so the followup observations are quite encouraged
(vsnet-campaign-sn 466). According to IAUC 7961, a spectroscopy of
SN 2002er at the INT on La Palma revealed that it is of type Ia,
about 10 days before maximum on Aug. 26.93. The host-galaxy
extinction also exist as well as the Milky Way one, so the expected
maximum for typical SN Ia is mag about 15.3 (vsnet-campaign-sn 468).
SN 2002es (RA = 03h23m47s.23, Dec = +40d33'53".5)
SN 2002es was discovered on LOTOSS KAIT images. It was about
16.4mag on August 23.5. UGC 2708, the host galaxy of SN 2002es
(offset 19"W, 25"N), is a lenticular galaxy, which produce SN Ia
only. The reported magnitude is consistent with the expected
maximum for typical SN Ia (vsnet-campaign-sn 466).
SN 2002et (RA = 20h08m31s.02, Dec = -25d27'37".5)
SN 2002et was discovered on LOTOSS KAIT images. It was about
16.5mag on August 24.3. The host galaxy of SN 2002et is MCG
-04-47-10 (offset 2"W, 7"S), which is a open spiral galaxy. The
reported magnitude is as bright as the expected maximum for SN Ia
(vsnet-campaign-sn 466).
IW And (RA = 01h01m08s.82, Dec = +43d23'27".3)
An outburst to 14.9mag was reported by T. Kinnunen on August 24
(vsnet-campaign-dn 2751).
SU Tau (RA = 05h49m03s.7, Dec = +19d04'21)"
M. Verdenet reported 11.7mag on August 18, which may indicate that
the object again became fainter (vsnet-campaign-rcb 66).
V592 Her (RA = 16h30m51s.60, Dec = +21d17'35".5)
A possible outburst was reported on August 28, but was not
confirmed (vsnet-campaign-dn 2757, 2758).
AQ Eri (RA = 05h06m12s.99, Dec = -04d08'01".6)
The object is now in a possible superoutburst, which was first
detected at 12.9mag by R. Stubbings on August 27 (vsnet-campaign-dn
2756). The outburst continues (vsnet-campaign-dn 2772).
New variable star in M31 (RA = 00h42m30s.9, Dec = +41d06'13")
K. Hornoch reported a new variable star in M31. On the DSS-II red
plates, the star is not present at limiting magnitude of R=20.5.
The object was first detected on 2001 August 16 at R=17.9mag, and
then confirmed in 2002 August. V-R index of this variable is larger
than of surrounding stars with comparable brightness, roughly
estimated of about 1-1.5 mag. Probably large amplitude and large
V-R index suggest, that it may be a Mira-type variable. Following
to his report, T. Kato suspected that the object might be a nova in
M31 (vsnet-campaign-nova 964).
(continuous targets)
AM Her (RA = 18h16m13s.4, Dec = +49d52'03".1)
The object is still faint at 15th mag (vsnet-campaign-polar 9).
BL Lac (RA = 22h02m42s.86, Dec = +42d16'37".6)
A brightening to 14.4mag was reported by J. Ripero on August 30
(vsnet-campaign-blazar 269).
MisV1147 (RA = 22h54m03s.78, Dec = +58d54'02".1)
As reported by M. Simonsen, MisV1147 (emission-line star, still
unknown classification) has undergone an unexpected dramatic fading
(14.2mag since August 28). The faint state was also confirmed on
August 31 at <14.7mag by M. Simonsen (vsnet-campaign-unknown 96). If
the star is a Herbig Ae/Be star, this episode may be related to
"eclipse"-like fading of this class of stars. Spectroscopic and
polarimetric observations, and multicolor photometry are encouraged
(vsnet-campaign-unknown 95).
SN 2002ap (RA = 01h36m23s.85, Dec = +15d45'13".0)
A. Henden reported his observations of V=17.747 and B-V=0.327 on
August 31 (vsnet-campaign-sn2002ap 204).
V729 Sgr (RA = 19h16m49s.15, Dec = -26d14'33".2)
The object experienced an outburst to 13.2mag on August 29
detected by R. Stubbings (vsnet-campaign-dn 2764).
V893 Sco (RA = 16h14m45s.26, Dec = -28d39'30".3)
An outburst to 12.9mag was reported by R. Stubbings on August 29
(vsnet-campaign-dn 2763).
BF Ara (RA = 17h38m10s.40, Dec = -47d10'43".4)
The data from P. Nelson shows superhumps decreased in amplitude
from 0.1mag on August 23 to 0.05mag on August 25 (vsnet-campaign-dn
2752). The superhumps detected by P. Nelson were rather narrow
(sharp), which are unlike many of other SU UMa stars
(vsnet-campaign-dn 2753). The superoutburst continued until August
27, when it entered a rapid fading phase (vsnet-campaign-dn 2754,
2765). During the fading phase, the light curve obtained by
P. Nelson shows double-wave superhumps (vsnet-campaign-dn
2759). R. Stubbings detected a rebrightening to 14.9mag on September
1 (vsnet-campaign-dn 2779).
AH Her (RA = 16h44m09s.99, Dec = +25d15'02".1)
An outburst from standstill was observed on August 27
(vsnet-campaign-dn 2760).
ES Aql (RA = 19h32m21s.58, Dec = -00d11'31".2)
The object has remained at about 13.2-13.4mag. The fading trend
seems to stop (vsnet-campaign-rcb 67).
V803 Cen (RA = 13h23m44.5s, Dec = -41d44'30".1)
As reported by R. Stubbings, the object experienced a sharp fading
to <14.8mag on August 26, and then recovered on August 27
(vsnet-campaign-dn 2755).
GU Sgr (RA = 18h24m15s.57, Dec = -24d15'26".1)
The object has still remained at the faint state
(vsnet-campaign-rcb 68).
HR Car (RA = 10h22m53s.89, Dec = -59d37'28".0)
S. Otero noticed that the long brightening of HR Car deserves more
attention. He found out that it has been brightening continuously
since 1967 to the preent, as if it was in an eta Carinae-like event
of dust and gas dispersion. The brightening has become steeper
since the very end of 1990 when mean magnitude rose from 8.0 - 8.3
to 7.5. By the end of August 2001, the star reached a
record-breaking maximum of V=6.7 and the current variations are now
in the range 6.7 - 7.2 (vsnet-campaign-sdor 19).
SN 2002ej (RA = 17h05m22s.62, Dec = +75d24'24".2)
In IAUC 7963, the Asiago team has revealed that it is of type II,
about 2 weeks after maximum on Aug. 30.0 (vsnet-campaign-sn 469).
*** Future schedule ***
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]
International Workshop
HIGH RESOLUTION X-RAY SPECTROSCOPY with XMM-NEWTON and CHANDRA
24th and 25th October 2002
For more details, visit the workshop website:
http://vsnet.mssl.ucl.ac.uk/~gbr/rgs_workshop/
[vsnet-campaign-xray 152]
International Symposium: The Universe viewed in gamma-rays
--- Univ. Tokyo Workshop 2002 ---
September 25-28, 2002, Kashiwa, Chiba, Japan
http://icrhp9.icrr.u-tokyo.ac.jp/Symp2002.html
[vsnet-campaign-blazar 264]
[vsnet-campaign-blazar 265]
[vsnet-campaign-grb 7]
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]
NEW X-RAY RESULTS FROM CLUSTERS OF GALAXIES AND BLACK HOLES
34th COSPAR Scientific Assembly
10th to 12th October 2002 - Houston, Texas
For more information, visit the session website:
www.mssl.ucl.ac.uk/www_astro/cospar
[vsnet-campaign-xray 124]
[vsnet-campaign-agn 2]
[vsnet-campaign-xray 133]
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]
34TH COSPAR - GRB AFTERGLOW PHYSICS
HOUSTON, TX, USA, 10-19 OCTOBER 2002
Main Scientific Organizer (MSO):
Elena Pian - INAF, Astronomical Observatory of Trieste, Italy -
pian@ts.astro.it
http://vsnet.ts.astro.it/topics/topix.html
[vsnet-campaign-grb 1]
*** General information ***
V838 Mon
CCD image taken by D. West:
http://hometown.aol.com/dwest61506/page5.html
[vsnet-campaign-v838mon 375]
How to estimate magnitudes of V838 Mon (by A. Henden),
see [vsnet-campaign-v838mon 376, 378]
Paper on astro/ph, by S. Kimeswenger et al.
see [vsnet-campaign-v838mon 377]
Observation by S. Kiyota, see [vsnet-campaign-v838mon 379]
V729 Sgr
Eclipse ephemeris, see [vsnet-campaign-dn 2764]
V893 Sco
Eclipse ephemeris, see [vsnet-campaign-dn 2763]
HR Car
Recent light curve by S. Otero;
http://ar.geocities.com/varsao/Curva_HR_Car.htm
[vsnet-campaign-sdor 19]
AB Nor
Light curve of growing superhumps:
http://vsnet.kusastro.kyoto-u.ac.jp/pub/vsnet/DNe/AB_Nor/absh.gif
[vsnet-campaign-dn 2786]
(This summary can be cited.)
Regards,
Makoto Uemura
Return to Daisaku Nogami
vsnet-adm@kusastro.kyoto-u.ac.jp
VSNET Home Page