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[vsnet-campaign-news 196] News from VSNET
*** News from VSNET ***
The new eclipsing SU UMa-type dwarf nova, XZ Eri started rapid
fading from the 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 February 10, 2003, as VSNET campaign
circulation 1369
[Note a large part of detailed information is posted to vsnet-campaign
sub-lists].
VSNET Weekly Campaign Summary
*** Last week news ***
(new targets)
SN 2003ab (RA = 09h19m13s.26, Dec = +48d58'09".1)
A host galaxy of SN 2003ab is UGC 4930, a distant spiral galaxy.
The expected maximum for typical SN Ia is mag about 17.1
(vsnet-campaign-sn 552). The spectrum taken by the UCB team on
Feb. 4 revealed that it was type II SN within a few weeks after the
explosion (vsnet-campaign-sn 553).
SN 2003ac (RA = 12h21m47s.35, Dec = +25d52'33".1)
A host galaxy of SN 2003ac is IC 3203, an edge-on spiral galaxy.
It is superimposed on the disk. The expected maximum for typical
SN Ia is mag about 16.6, but the reported magnitudes were fainter
(18.9mag) (vsnet-campaign-sn 552). It actually turned out to be of
type II. It is reported to be resemble with SN II 1987K
(vsnet-campaign-sn 553).
SN 2003ad (RA = 14h56m28s.07, Dec = +45d21'09".2)
A host galaxy of SN 2003ad is 2MASXi J1456273+452112, a small
barred-spiral galaxy. The SN is superimposed on the outermost
part of the disk (vsnet-campaign-sn 553). The CfA team took a
spectrum of SN 2003ad on Feb 6.53, which revealed that it was a type
II SN soon after explosion. The recession velocity of the host
galaxy is measured as 10500 km/s, which suggest that it is somewhat
bright event as a core-collapse type SN (vsnet-campaign-sn 555).
SN 2003ae (RA = 09h28m22s.58, Dec = +27d26'40".7)
A host galaxy of SN 2003ae is 2MASXi J0928225+272641, a small
galaxy. The CfA team took a spectrum on Feb. 6.29, which revealed
that it was type Ia SN about a week before maximum. They note
that the discovery was made 2 weeks still more before the
spectroscopy (vsnet-campaign-sn 554).
SN 2003af (RA = 11h10m21s.69, Dec = +23d24'50".9)
A host galaxy of SN 2003af is 2MASXi J1110213+232453, a dim
galaxy. The SN is also seen on the images taken on Jan. 19
(vsnet-campaign-sn 555).
SN 2003ag (RA = 11h26m01s.82, Dec = +01d59'02".8)
A host galaxy of SN 2003ag is UGC 6440, a barred-spiral galaxy.
The SN is located between bright arms. The reported magnitude
(16.5C, 16.3C mag) is consistent with the expected maximum for
typical SN Ia (vsnet-campaign-sn 556).
SN 2003ah (RA = 04h43m08s.54, Dec = +00d46'00".4)
A host galaxy of SN 2003ah is an anonymous edge-on spiral galaxy,
which is located about 1' north of a pair of galaxies UGC 3141. The
SN is superimposed on the outermost disk region. If the host galaxy
is the same distance as UGC 3141, the expected maximum for typical
SN Ia is mag about 16.0 (vsnet-campaign-sn 556).
SN 2003ai (RA = 13h00m58s.68, Dec = +39d51'24".5)
A host galaxy of SN 2003ai is IC 4062, an apparent elliptical(?)
galaxy and a probable member of the cluster AWM 6. The discovery
magnitude (17.0C, 16.9C mag) is consistent with (but possibly
slightly brighter than) the expected maximum for typical SN Ia
(vsnet-campaign-sn 556).
BY Cam (RA = 05h42m48s.90, Dec = +60d51'31".8)
The polar BY Cam is recently reported to be active and show
short-term variations of 14.1-14.9mag (vsnet-campaign-polar 21).
GSC 6248:1255 (RA = 17h37m22s.694, Dec = -16d21'11".09)
D. West reported that the star GSC 6248:1255 (in the field of
V2540 Oph) appears to be variable. This is a red star (M type).
The variability range is reported to be 11.76-11.21V mag
(vsnet-campaign-unknown 183).
(continuous targets)
XZ Eri (RA = 04h11m25s.76, Dec = -15d23'24".3)
T. Kato reported that large negative eclipse O-C's were suddenly
recorded on a single night on Jan. 29. Otherwise the O-C change has
been smooth and has not show such a large deviation
(vsnet-campaign-dn 3410). On Feb. 4, the superhumps became less
prominent. On Feb. 5, the superhump maxima were superimposed on the
eclipses, with a possibly slight increase of the amplitude. The
most notable phenomenon is the emergence of very deep eclipses. On
Feb. 5, the depth of the eclipses reached nearly 1.6 mag
(vsnet-campaign-dn 3413). A sudden, rapid fading was reported on
Feb. 6 by K. Torii (vsnet-campaign-dn 3414). The fading rate looks
to be smaller than those of SU UMa stars with similar periods
(vsnet-campaign-dn 3420). The object still showed strong
superhumps, with a noticeable beat phenomenon on Feb. 6, and
possibly on Feb. 7 (vsnet-campaign-dn 3424).
BC UMa (RA = 11h52m15s.88, Dec = +49d14'42".0)
The light curve obtained on Feb. 3 showed that the initial fading
has stopped. The amplitude of the superhumps has grown to 0.3
mag, with a profile of fully grown superhumps (vsnet-campaign-dn
3409, 3411). T. Kato performed period analysis using the combining
data set reported by the VSNET collaboration team, and reported that
the best superhump period between Feb. 3 and 5 is determined to be
0.06447(2) d. This period generally confirms the 2000 result
(representative period 0.06452 d)(vsnet-campaign-dn 3412). T. Kato
furthermore reported on Feb. 10 that the period derivative has been
determined to be dot(P)/P = +4*10^(-5) (vsnet-campaign-dn 3423,
3426). The superoutburst is still ongoing (vsnet-campaign-dn 3415).
Z UMi (RA = 15h02m01s.35, Dec = +83d03'48".7)
The object is still at a bright state (vsnet-campaign-rcb 91).
delta Sco (RA = 16h00m19s.9, Dec = -22d37'17")
S. Otero reported that delta Sco is at 1.80 mag on February 8,
keeps fading slowly after its huge November brightening
(V=1.6)(vsnet-campaign-be 211).
V838 Mon (RA = 07h04m04s.816, Dec = -03d50'50".94)
The spectrum taken by M. Fujii on Feb. 6 looks later than M6
(vsnet-campaign-v838mon 415).
SN 2003X (RA = 18h12m05s.67, Dec = +29d09'17".3)
The spectrum taken by the UCB team on Feb. 4 revealed that it was
of type Ia, resembling SN Ia 1994D about a month after maximum. It
may be somewhat luminous than typical one (vsnet-campaign-sn 553).
SN 2003aa (RA = 10h46m36s.82, Dec = +13d45'32".2)
The CfA team has revealed that it is type Ic supernova. The
spectrum taken on Feb. 2.31 resembles that of SN Ic 1994I four
days before maximum (vsnet-campaign-sn 552).
IGR J16318-4848 (RA = 16h31m52s, Dec = -48d48'.5)
W. Liller reported no new object brighter than 11.5mag was found
around the position of this X-ray transient (vsnet-campaign-xray
187). B. Monard also reported that no new star was found down to
a magnitude of 19.0CR in comparison to images of the DSS
(vsnet-campaign-xray 188).
OY Car (RA = 10h06m22s.46, Dec = -70d14'04".4)
The object was in superoutburst during the last week
(vsnet-campaign-dn 3417).
IP Peg (RA = 23h23m08s.7, Dec = +18d24'59".1)
The outburst continues (vsnet-campaign-dn 3419).
GZ Cnc (RA = 09h15m51s.70, Dec = +09d00'50".2)
An outburst of 14.6mag was reported by M. Simonsen on Feb. 6
(vsnet-campaign-dn 3416). It was confirmed at 13.7mag by K. Torii.
This outburst seems to have started significantly earlier than
expected from the recent periodicity (vsnet-campaign-dn 3418).
During the outburst on Feb. 6, slower (40-60 min) oscillations were
predominant, and then started fading, as detected in G. Bolt's
observations. There was no clear evidence of spike-like
short-period oscillations, as observed during the preceding
outburst (vsnet-campaign-dn 3425). The light curve obtained by the
Nyrola team on Feb. 7 indicated that GZ Cnc faded from the (small?)
outburst. There were 30-60 min slow variations, but the spike-like
signals were absent (vsnet-campaign-dn 3421).
MisV1147 (RA = 22h54m03s.78, Dec = +58d54'02".1)
The object further faded (vsnet-campaign-unknown 182). C. Lloyd
commented that the fading is still consistent with a period of about
32 days, while several another fadings punctuated the cycle
(vsnet-campaign-unknown 184).
SN 2002kk
The LBNL team has revealed that SN 2002kk was a type Ia SN, about
2 months after maximum on Nov. 9. It is consistent with the light
curve, which suggests the maximum occurred around Aug. 26. It is an
old and distant event (vsnet-campaign-sn 554).
eta Gem (RA = 06h14m52s.87, Dec = +22d30'24".5)
D. West reported that he is working on the ephemeris for eta Gem.
His calculations show eta Gem in eclipse on approximately 02
August 2004 (vsnet-campaign-ecl 57, 58).
*** Future schedule ***
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]
[vsnet-campaign-xray 172]
Light curve provided by S. Otero:
http://ar.geocities.com/varsao/Curva_Eta_Carinae.htm
[vsnet-campaign-sdor 22]
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]
WEBT campaign on Mkn 421
M. Villata announced possible WEBT campaign on Mkn 421, in
December 2002 and February-March 2003, to be carried out during
multifrequency campaigns.
The relevant information on the MW campaign of December 2-16 is at
the VERITAS site <http://veritas.sao.arizona.edu> .
[vsnet-campaign-blazar 287]
[vsnet-campaign-blazar 288]
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]
[vsnet-campaign-sn 512]
*** General information ***
IGR J16318-4848
CCD image of the field by B. Monard:
http://vsnet.kusastro.kyoto-u.ac.jp/pub/vsnet/Xray/IGRJ16318-4848/monard1.gif
[vsnet-campaign-xray 189]
XZ Eri
Eclipse ephemeris, see [vsnet-campaign-dn 3422]
V838 Mon
Spectrum taken by M. Fujii on Feb. 6:
http://vsnet1.harenet.ne.jp/~aikow/v838mon_20030206.gif
[vsnet-campaign-v838mon 415]
V,Rc,Ic observations by S. Kyota in January, see
[vsnet-campaign-v838mon 416]
Discussion about "Why Aren't Arne's Sequences Solid Gold?"
[vsnet-campaign-ccd-discussion 22, 23, 24, 25]
Discussion about "CCD-V Vs visual observations = U ORIONIS"
[vsnet-campaign-ccd-discussion 26, 27, 28]
(This summary can be cited.)
Regards,
Makoto Uemura
Return to Daisaku Nogami
vsnet-adm@kusastro.kyoto-u.ac.jp
VSNET Home Page