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*** News from VSNET ***
V4745 Sgr (=Nova Sgr 2003) experienced a dramatic rebrightening.
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 12, 2003, as VSNET campaign
circulation 1388
[Note a large part of detailed information is posted to vsnet-campaign
sub-lists].
VSNET Weekly Campaign Summary
*** Last week news ***
(new targets)
SN 2003ed (RA = 13h47m45s.36, Dec = +36d18'20".3)
SN 2003ed was discovered by K. Itagaki on May 3 at mag 15.2.
The position is about 3" east and 4" north of the nucleus of the
host galaxy NGC 5303. It was below mag 19 on Apr. 27. The CfA team
has revealed that the SN was of type II soon after explosion
(vsnet-campaign-sn 617).
SN 2003ee (RA = 11h33m24s.50, Dec = -09d59'26".4)
SN 2003ee is hosted by an anonymous compact blue galaxy. The
spectrum taken at the Las Campanas Observatory on May 5.10 UT
suggests that it is a type IIn supernova with a blue continuum, at z
= 0.021. The observed brightness is comparable to the expected
maximum of SN Ia, and it remains blue a month or more from the
explosion, which suggest that this SN is somewhat peculiar
(vsnet-campaign-sn 619).
EG Aqr (RA = 23h25m19s.2, Dec = -08d18'20")
T. Kato reported that, according to ASAS-3 data, EG Aqr may have
brightened (reported mag 14.25). This may be a noise, but it would
be worth checking (vsnet-campaign-dn 3645).
KX TrA (RA = 16h44m35s.2, Dec = -62d37'15")
According to ASAS-3 data, KX TrA (ZAND, Hen1242) is slowly
brightening. The currect magnitude is about V=11.5-11.6
(vsnet-campaign-symbio 66).
TV Crv (RA = 12h20m23s.56, Dec = -18d27'02".7)
As reported by R. Stubbings on May 9, the short-period,
large-amplitude, SU UMa-type dwarf nova TV Crv is in outburst
(13.1mag). The last confirmed outburst was in 2002 May - June
(superoutburst)(vsnet-campaign-dn 3647). G. Bolt performed
time-series observation, which detected fully grown superhumps
(amplitude 0.3 mag). From the light curve, it looks likely that the
outburst is 3-day old, suggesting that the outburst started around
May 7 (vsnet-campaign-dn 3653).
V729 Sgr (RA = 19h16m49s.15, Dec = -26d14'33".2)
As reported by R. Stubbings on May 9, the eclipsing dwarf nova
V729 Sgr is in outburst. This object is not an SU UMa star, but is
likely an SS Cyg (or Z Cam) star (vsnet-campaign-dn 2648). G. Bolt
performed time-series observation on May 10 and detected an eclipse
during the outburst. The eclipse was rather shallow (as expected)
with a depth of 0.1-0.2 mag and a duration of 30 min. From the
eclipse shape and depth, the outer part of the accretion disk was
likely eclipsed. The eclipse light curve was rather asymmetric,
probably caused by a pre-eclipse hump-like variation. The light
curve outside the eclipses was rather variable up to 0.1 mag
(vsnet-campaign-dn 3654).
AS 210 (RA = 16h51m20s.4, Dec = -26d00'27".1)
According to ASAS-3 data, the symbiotic star AS 210 unmistakably
shows Mira-type variation with a period of 400 d. Range 11.9 -
<13.5 V (vsnet-campaign-symbio 67).
Hen3-1761 (RA = 19h42m25s.3, Dec = -68d07'35".3)
According to ASAS-3 data, the symbiotic star Hen3-1761 is
confirmed to be variable. The variation is semiregular to
irregular with characteristic periods of 30-100 d. The range is
11.1-11.8 V (vsnet-campaign-symbio 68).
CD-43.14304 (RA = 21h00m06s.3, Dec = -42d38'49".9)
According to ASAS-3 data, the symbiotic star CD-43.14304 is
confirmed to be variable. The variation is semiregular with a
characteristic period of 90 d. The range is 11.3-11.7 V
(vsnet-campaign-symbio 69).
Hen3-461 (RA = 10h39m08s.5, Dec = -51d24'11".9)
According to ASAS-3 data, the symbiotic star Hen3-461 shows
relatively large-amplitude variation. The range is 12.1-13.1 V.
The variations look semiregular (P around 100 d?)
(vsnet-campaign-symbio 70).
Hen3-863 (RA = 13h07m43s.8, Dec = -48d00'23".0)
According to ASAS-3 data, the symbiotic star Hen3-863 slow
variations. The range in 12.5-12.8 V (vsnet-campaign-symbio 71).
CD-36.8436 (RA = 13h16m01s.6, Dec = -37d00'11".9)
According to ASAS-3 data, the symbiotic star CD-36.8436 shows
low-amplitude semiregular variations (period about 100 d). The
range in 10.5-10.8 V (vsnet-campaign-symbio 72).
Hen3-1103 (RA = 15h48m28s.5, Dec = -44d19'00".9)
According to ASAS-3 data, the symbiotic star Hen3-1103 shows
low-amplitude slow variations. The range in 12.2-12.5 V
(vsnet-campaign-symbio 73).
AS270 (RA = 18h05m33s.6, Dec = -20d20'44".6)
According to ASAS-3 data, the 2001 outburst of the symbiotic star
AS270 was clearly recorded. The rise took about 80 d. The range
of variability is 11.5-13.8 V. This outburst was also observed by
VSNET members. The object is now near quiescence
(vsnet-campaign-symbio 74).
AS276 (RA = 18h09m09s.6, Dec = 41d13'26".0)
According to ASAS-3 data, the symbiotic star AS 276 shows
low-amplitude irregular variations. The range is 13.3 - 13.6 V
(vsnet-campaign-symbio 75).
AS316 (RA = 18h42m33s.0, Dec = -21d17'48".0)
According to ASAS-3 data, the symbiotic star AS 316 shows
low-amplitude irregular variations. The range is 13.1 - 13.4 V
(vsnet-campaign-symbio 76).
SN 2003ef (RA = 12h49m42s.25, Dec = -11d05'29".5)
SN 2003ef is hosted by NGC 4708, a spiral galaxy. The expected
maximum of typical SN Ia is mag about 15.5. Note that a faint
galaxy is superimposed on the northwest part of NGC 4708
(vsnet-campaign-sn 620).
(continuous targets)
V2527 Oph (RA = 17h22m04s.3, Dec = -19d49'08")
The May 4 data did not reveal a superhump signal more than 0.1 mag
(vsnet-campaign-dn 3638). In the light curve obtained by K. Tanabe
on May 5, there were slow modulations (amplitude up to 0.3 mag) with
periods of 1-2 hr, but it is not clear whether this modulation is
associated with superhumps. It was recored by 0.9 mag fainter on May
8 than on May 5, indicating a further fading (vsnet-campaign-dn 3649).
The object faded from the outburst (vsnet-campaign-dn 3633).
RX Vol (RA = 08h39m32s.30, Dec = -66d17'39".2)
T. Kato reported that the May 5 data yielded the best superhump
period of 0.06123(8) d. All the hump maxima between May 4 and 5
have been smoothly linked with a single period (vsnet-campaign-dn
3624). A refined superhump period of 0.06117(5) d was reported on
May 7 (vsnet-campaign-dn 3627). On May 8, T. Kato reported that
there is evidence for a period decrease of superhumps. The initial
(0.060 d) variation seems to bear some resemblance to early
superhumps (vsnet-campaign-dn 3637). After that, the superhump
amplitude decreased rather rapidly (vsnet-campaign-dn 3641). Then,
light curves showed a regrowth of superhumps with a possible period
lengthening (vsnet-campaign-dn 3644). The superoutburst is now
ongoing (vsnet-campaign-dn 3630).
OU Vir (RA = 14h35m00s.14, Dec = -00d46'07".0)
The superhump maxima on May 6-7 were superimposed on eclipses,
making a complex feature. The beat phenomenon is prominent, as
expected for this high-inclination system. On May 7-8, the eclipse
again became sharp and superhumps moved to outside the eclipses.
The superhump period analysis shows a preliminary period of 0.07505
d, and there is a slight tendency of a period decrease at dot(P)/P =
-(several)x10^(-5). Combined with the eclipse period, the
fractional superhump excess with the new period is 3.1%, which looks
like a more acceptable value (vsnet-campaign-dn 3640, 3643, 3646,
3656). There is some indication of a double hump on May 10
(vsnet-campaign-dn 3652). The superoutburst is (vsnet-campaign-dn
3622, 3625, 3631).
SN 2003dt (RA = 20h47m17s.56, Dec = +00d18'42".8)
The CfA team reported that SN 2003dt was type Ia SN several weeks
after maximum on May 5.45 (vsnet-campaign-sn 618).
CR Boo (RA = 13h48m55s.42, Dec = +07d57'30".3)
The object has apparently resumed its "superoutbursting" phase
(vsnet-campaign-dn 3634).
AD Men (RA = 06h04m30s.836, Dec = -71d25'22".25)
It seems to be still in a long outburst since April 28
(vsnet-campaign-dn 3632, 3639). H. Yamaoka reported that the marked
object in VSNET page or Downes' online chart shows no significant
change among the DSS images, and a star 0.2' ESE of the marked
object is true "AD Men" (at the above position) (vsnet-campaign-dn 3650).
SN 2003dw (RA = 16h45m51s.10, Dec = +59d37'38".0)
The spectrum taken on May 5.34 by the CfA team revealed that it
was type Ia SN near maximum (vsnet-campaign-sn 618).
SN(?) 2003ec (RA = 15h46m16s.67, Dec = +02d24'48".7)
K. Itagaki reported that this object can be clearly seen on his
CCD images taken on 2001 May 13 and 2002 May 3, which suggests that
it is a foreground star. The Las Campanas spectrum of this object
on May 5.33 UT showed a featureless blue continuum
(vsnet-campaign-sn 619, vsnet-campaign-dn 3626).
SN 2003dq (RA = 11h04m45s.44, Dec = +15d26'49".4)
The Las Campanas spectrum on May 5.06 UT showed that it was type
II SN several weeks after explosion (vsnet-campaign-sn 619).
BI Cru (RA = 12h23m26s.0, Dec = -62d38'16")
S. Otero reported that the recent recovering trend of BI Cru
suggests not an eclipse, but a pulsation of the LPV. The red giant
of this symbiotic system is a mira with a 280 days period
(vsnet-campaign-symbio 64). However, T. Kato reported that the 2003
minimum is at least 1 mag fainter than the past Mira pulsation
minima, which indicates an eclipse-like event (vsnet-campaign-symbio 65).
V4745 Sgr (RA = 18h40m02s.54, Dec = -33d26'55".1)
A dramatic brightening to V=8.61mag, or 8.2-8.1mag was reported on
May 8. The nova resembles in many aspects the highly oscillating slow
nova V2540 Oph (vsnet-campaign-nova 1242, 1244, 1245, 1246, 1248).
Based on the spectrum taken by M. Fujii on May 8, T. Kato reported
that the object is an Fe II-class nova (vsnet-campaign-nova 1243).
BZ Cam (RA = 06h29m34s.49, Dec = +71d04'39".5)
The slightly faint state (~12.8mag) still continues
(vsnet-campaign-nl 116).
V551 Sgr (RA = 18h00m56s.46, Dec = -34d35'45".6)
The data obtained by K. Tanabe on April 27 clearly showed
V551 Sgr in outburst, but a preliminary analysis did not reveal the
presence of superhump-like modulations larger than 0.1 mag
(vsnet-campaign-dn 3657).
Var73 Dra (RA = 20h23m38s.193, Dec = +64h36m26s.91)
R. Ishioka reported that the last superoutburst lasted for 12 d,
with the averaged fading rate of 0.06 mag/d. Recent four
superoutburst including this one show the unusually short supercycle
of ~60 d (vsnet-campaign-dn 3635, 3636).
delta Sco (RA = 16h00m19s.9, Dec = -22d37'17")
S. Otero reported that it is recently 1.60-1.62mag, very bright
(vsnet-campaign-be 237).
V844 Her (RA = 16h25m01s.69, Dec = +39d09'25".9)
An outburst was reported on May 5 by G. Poyner and
P. A. Dubovsky. The most recent outburst (2002 December) was a
superoutburst. The star may have changed its outburst
characteristics (vsnet-campaign-dn 3629).
eta Car (RA = 10h45m03s.65, Dec = -59d41'03".7)
S. Otero reported that the object is getting brighter
(vsnet-campaign-sdor 33).
alpha Cyg (RA = 20h41m25s.80, Dec = +45d16'49".1)
Some reports show alpha Cyg is recently slightly fainter than
usual (vsnet-campaign-sdor 34, 36). D. West reported V=1.3 on May 9,
rather normal value (vsnet-campaign-sdor 35).
*** 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 ***
SN 2003ed
Spectrum taken by the CfA team:
http://cfa-www.harvard.edu/cfa/oir/Research/supernova/spectra/sn2003ed-20030505.flm.gif
[vsnet-campaign-sn 617]
OU Vir
Eclipse ephemeris, see [vsnet-campaign-dn 3623, 3642]
Light curve by K. Nakajima:
http://vsnet.kusastro.kyoto-u.ac.jp/pub/vsnet/OU_Vir/njh.gif
[vsnet-campaign-dn 3628]
Light curves by T. Vanmunster:
http://vsnet.cbabelgium.com
[vsnet-campaign-dn 3646, 3655]
V4745 Sgr
Spectrum taken by M. Fujii:
http://vsnet1.harenet.ne.jp/~aikow/v4745_sgr_20030508.gif
[vsnet-campaign-nova 1243]
V729 Sgr
Eclipse ephemeris, see [vsnet-campaign-dn 3648]
V838 Mon
Rc and Ic observations by S. Kiyota, see [vsnet-campaign-v838mon 424]
AD Men
VSNET page with a corrected identification:
http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/DNe/admen.html
[vsnet-campaign-dn 3651]
RS Oph
Sequence from RASNZ, see [vsnet-campaign-nova 1247]
Corrigendum:
In the last Campaign Summary,
SN 2003dv = POSSIBLE SUPERNOVA IN UGC 9638
.....
that of typical gravitational-collapsed event (M ~ 17)
^^^^^^
M ~ -17
Sorry for your confusion.
New VSNET E-mail Service
[vsnet-campaign-target] and [vsnet-campaign-report]
for more detailed information, see [vsnet-campaign-target 1]
(This summary can be cited.)
Regards,
Makoto Uemura
Return to the Powerful Daisaku Nogami
vsnet-adm@kusastro.kyoto-u.ac.jp
