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*** News from VSNET ***
GO Com, a suspected large-amplitude SU UMa star, was confirmed to be
an SU UMa star, and now in superoutburst.
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 9, 2003, as VSNET campaign
circulation 1396
[Note a large part of detailed information is posted to vsnet-campaign
sub-lists].
VSNET Weekly Campaign Summary
*** Last week news ***
(new targets)
GO Com (RA = 12h56m37s.0, Dec = +26d36'44")
As reported by C. Jones on June 2 (vsnet-outburst 5622), the
suspected large-amplitude SU UMa-type dwarf nova GO Com is
undergoing a bright outburst (mag 13.0-13.5). The most recent
confirmed outburst was in 1998 April. The only likely superoutburst
recorded in this decade was in 1995 August (vsnet-campaign-dn 3721).
The object then, tentatively, rapidly faded at ~1.0 mag/day, as
reported by D. Nogami (vsnet-campaign-dn 3722, 3727, 3726, 3728,
3729, 3730, vsnet-campaign 1395, 1396).
After this temporary fading, the object recovered to mag 13 on
June 4, as reported by P. Schmeer (vsnet-campaign-dn 3731).
T. Krajci detected well developed superhumps 0.4 mag. amplitude and
0.0635(4) d period. GO Com was thus finally confirmed to be the SU
UMa-type dwarf nova (vsnet-campaign-dn 3732, 3733, 3734, 3739).
A revised period of 0.06326(5) d was reported by T. Kato on June 6
(vsnet-campaign-dn 3738, 3742, 3748, 3749). The superhump amplitude
decreased to 0.2-0.25mag on June 5 (vsnet-campaign-dn 3740, 3741,
3747). There was a hint of low-amplitude (~0.03 mag) qausi-periodic
oscillations with periods of 6-7 min in June 5 light curves
(vsnet-campaign-dn 3742).
The object experienced a superhump period decrease around late
June 5. The superhump timings since late June 5 have been well
expressed by a single period of 0.06268 d. Compared to this period,
the period observed on the first night was longer by 1.5%
(vsnet-campaign-dn 3743, 3751). A similar evolution of superhumps
was confirmed by T. Vanmunster (vsnet-campaign-dn 3754). The
superhump amplitude further decreased to 0.15mag on June 7
(vsnet-campaign-dn 3756, 3755). On June 8, T. Kato reported a
period increase of superhumps. The period change may be alternately
interpreted as the effect of a "beat phenomenon" between the
superhump period and orbital period (vsnet-campaign-dn 3757). After
that, the superhump period again decreased (vsnet-campaign-dn 3763).
The superoutburst is now ongoing (vsnet-campaign-dn 3744, 3745,
3750, 3760, 3764).
SN 2003eo (RA = 11h03m09s.19, Dec = -05d46'09".4)
SN 2003eo was discovered by the NEAT team. The reported brightest
mag is 20.2 on Mar. 27.14 (vsnet-campaign-sn 629).
SN 2003ep (RA = 21h21m07s.34, Dec = +23d05'05".8)
SN 2003ep is hosted by NGC7053, a spiral? galaxy. The expected
maximum of typical SN Ia is consistent with the discovery
magnitude (15.7mag on May 17). The CfA team took a spectrum on June
4.46, which revealed that it was a reddened SN Ia, about 3-4 weeks
after maximum (vsnet-campaign-sn 630).
SN 2003ev (RA = 13h10m31s.80, Dec = -21d39'49".6)
SN 2003ev is hosted by 2MASX J13103164-2139555, an apparently
edge-on spiral galaxy. In its neighbourhood, there are some
galaxies with the recession velocities are about 3000 km/s or 7000
km/s. If the latter is near to that of the host galaxy, the
expected maximum for typical SN Ia is mag about 16.8
(vsnet-campaign-sn 629). The Las Campanas spectrum taken on June
4.19 shows a red continuum with broad undulations. Observed
features consistent with a highly reddened young SN Ic, but the firm
classification needs additional observation (vsnet-campaign-sn 632).
SN 2003fa (RA = 17h44m07s.72, Dec = +40d52'51".6)
The object was found near to MCG +07-36-33, a possibly nearby
spiral galaxy. The appearance of the galaxy is rather small, and
the new object seems to be located too far from the center of the
galaxy. And, if it belongs to MCG +07-36-33, it is somewhat
subluminous for SN (M about -14.5) (vsnet-campaign-sn 629). The CfA
team took a spectrum on June 5. It shows that this object was
really SN of type Ia, well before maximum. Si II absorption was
shallow, which may indicate that it is a luminous SN Ia
(vsnet-campaign-sn 631, 632). The CfA team has remeasured the
recession velocity of MGC +07-36-33 and obtained it as 11800 km/s,
so the NED value is in error. It is as same as that of SN Ia
2003fa, so this galaxy indeed likely hosts SN 2003fa
(vsnet-campaign-sn 634).
HS Vir (RA = 13h43m38s.5, Dec = -08d14'04".1)
An outburst to 14.8mag was reported on June 2 by R. Stubbings.
The object further brightened to 14.0mag on June 4. A superoutburst
may have started (vsnet-campaign-dn 3737).
SN 2003ex (RA = 13h27m32s.31, Dec = +05d31'14".4)
SN 2003ex is hosted by a compact anonymous galaxy (rmag around 16
in USNO-A2.0). Typical uncertainty of the NEAT data is reported as
"up to 0.4 mag" (vsnet-campaign-sn 630).
SN 2003ey (RA = 14h20m03s.28, Dec = -08d28'40".0)
SN 2003ey is hosted by a round-shaped anonymous galaxy (rmag about
15 in USNO-A2.0) (vsnet-campaign-sn 630). The Las Campanas spectrum
taken on 4.27 UT revealed that it was type Ia SN about 5 days after
maximum. The recession velocity of the host galaxy was measured as
v_r ~ 20000 km/s (vsnet-campaign-sn 632).
SN 2003ez (RA = 12h43m11s.87, Dec = -02d30'04".1)
SN 2003ez is hosted by PGC 42782, a barred-spiral galaxy. The
expected maximum for typical SN Ia is consistent with the
discovery magnitude (17.5-17.4mag on June 3 and 4)
(vsnet-campaign-sn 630). The Las Campanas spectrum obtained on June
4.13 UT revealed that it was possibly luminous SN Ia, about 3 days
before maximum (vsnet-campaign-sn 632).
NGC6822nova2003 (RA = 19h45m04s.18, Dec = -14d45'46".5)
This object is located about 1"W and 3"N of a foreground star of
mag about 18.5. NGC 6822 is a dwarf irregular galaxy in the local
group (Barnard's galaxy). Its distance is comparable to that of
Andromeda galaxy. The absolute magnitude at discovery is about
-5.0, so it can be a nova past maximum (vsnet-campaign-sn 630).
SN 2003fb (RA = 20h11m50s.33, Dec = +05d45'37".6)
SN 2003fb is hosted by UGC 11522, a spiral galaxy. The ANU group
took a spectrum of this object on June 6.7 UT, which revealed that
it is a type-II SN (vsnet-campaign-sn 633). The Las Campanas
spectrum taken on June 7.33 UT confirms this classification
(vsnet-campaign-sn 634).
SN 2003fc (RA = 20h08m22s.08, Dec = -17d36'30".5)
SN 2003fc is hosted by 2MASX J20082222-1736386, a small spiral(?)
galaxy (vsnet-campaign-sn 633). The Las Campanas spectrum (June
7.37 UT) and the UCB group spectrum (June 7 UT) shows that it is SN
Ic near (a few days before) maximum (vsnet-campaign-sn 634).
(continuous targets)
V803 Cen (RA = 13h23m44s.5, Dec = -41d44'30".1)
A bright outburst (12.6mag) was reported by R. Stubbings on June
4. In the N. D. Butterworth's data, the light curve clearly
indicated the presence of 0.06 mag superhumps. The period determined
from this observation is 0.018674(6) d, which agrees with the
"nominal superhump period" of this system within errors. The
superoutburst entered a rapid fading phase on June 8
(vsnet-campaign-dn 3735, 3746, 3752, 3758, 3759, 3761, 3762, 3765).
SN 2003ed (RA = 13h47m45s.36, Dec = +36d18'20".3)
The UCB team took spectra on May 25, which show striking
resemblance to that of SN IIb 1993J. He I lines with P-Cyg
profile is now emerged (vsnet-campaign-sn 633).
SN 2003em (RA = 02h09m20s.23, Dec = -23d24'53".0)
The Las Campanas spectrum taken on June 4.42 shows that it was a
type Ia SN about 40 days after maximum (vsnet-campaign-sn 632).
RS Oph (RA = 17h50m13s.56, Dec = -06d42'30".6)
The relatively bright state still continues
(vsnet-campaign-nova 1275, 1276, 1278).
V405 Vul (RA = 19h53m05s.0, Dec = +21d14'50")
No outburst has been reported (vsnet-campaign-dn 3725).
rho Cas (RA = 23h54m22s.99, Dec = +57d29'58".7)
No major fading has been observed yet. Recent observations can be
seen at [vsnet-campaign-rhocas 18, 19].
PU CMa (RA = 06h40m47s.67, Dec = -24d23'14".6)
The object has been in a post-superoutburst stage. Late
superhumps were still very prominent (vsnet-campaign-dn 3723).
OU Vir (RA = 14h35m00s.14, Dec = -00d46'07".0)
The post-superoutburst rebrightening lasted for more than 4 days,
which is unusually long for a (usually short) post-superoutburst
rebrightening. During the June 2 run, the object seems to show a
fading trend, possibly suggesting that the phenomenon is on the
decay phase. During this rebrightening, sharp and deep (1.5 mag)
eclipses have been observed. The light curve of the eclipses
suggests that the main light source is concentrated in a small
region (vsnet-campaign-dn 3724).
V4745 Sgr (RA = 18h40m02s.54, Dec = -33d26'55".1)
The object is fading from the third maximum (vsnet-campaign-nova
1277, 1279).
V735 Sgr (RA = 17h59m51s.7, Dec = -29d33'50")
A brightening to 13.6mag was reported on June 4
(vsnet-campaign-unknown 206).
V1413 Aql (RA = 19h03m46s.84, Dec = +16d26'17".1)
A summary of the recent eclipse was shown in [vsnet-campaign-ecl
80, vsnet-campaign-symbio 77].
MV Lyr (RA = 19h07m15s.93, Dec = +44d01'10".7)
The very bright state continues (vsnet-campaign-nl 125).
V Sge (RA = 20h20m14s.75, Dec = +21d06'09".0)
V Sge is now in a faint state (vsnet-campaign-nl 126).
eta Car (RA = 10h45m03s.65, Dec = -59d41'03".7)
Recent observations are shown in [vsnet-campaign-sdor 45].
EE Cep (RA = 22h09m22s.8, Dec = +55d45'24")
The eclipse is now ongoing (vsnet-campaign-ecl 79, 81).
IX Dra (RA = 18h12m32s.2, Dec = +67d04'41")
An outburst (15.2mag) was reported by P. A. Dubovsky on June 3
(vsnet-campaign-dn 3736).
MisV1147 (RA = 22h54m03s.78, Dec = +58d54'02".1)
A new fading was reported on June 7 (vsnet-campaign-unknown 207).
*** 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 ***
SN 2003fa
The CfA spectrum:
http://cfa-www.harvard.edu/cfa/oir/Research/supernova/spectra/snvar-20030605.flm.gif
[vsnet-campaign-sn 631]
Flares in Mira stars, see [vsnet-campaign-mira 63, 64, 65]
GO Com
Images by T. Vanmunster:
http://vsnet.cbabelgium.com
[vsnet-campaign-dn 3748, 3753]
V803 Cen
Superhump profile observed by Neil D Butterworth:
http://vsnet.kusastro.kyoto-u.ac.jp/pub/vsnet/DNe/V803_Cen/sh0306.gif
[vsnet-campaign-dn 3752]
delta Vel
Primary eclipse observed by S. Otero, see [vsnet-campaign-deltavel 40]
(This summary can be cited.)
Regards,
Makoto Uemura
Return to the Powerful Daisaku
vsnet-adm@kusastro.kyoto-u.ac.jp
