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[vsnet-campaign-news 192] News from VSNET




                       ***  News from VSNET  ***

UV Gem experienced an unprecedented period change of superhumps during
an early superoutburst phase.  

  For more detail information about these objects, 
see below, "VSNET Weekly Campaign Summary" of the last week.

---------------------------------------------------------------------------
 
  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

----------------------------------------------------------------------------

The following was issued on January 13, 2003, as VSNET campaign
circulation 1364
[Note a large part of detailed information is posted to vsnet-campaign
sub-lists].

VSNET Weekly Campaign Summary

*** Last week news ***

(new targets)
  SN 2003B	        (RA = 02h46m13s.78, Dec = -30d13'45".1)

    SN 2003B was discovered visually by R. Evans.  It was revealed to
  be a type II SN a few weeks after explosion on Jan 6 UT.   The host
  galaxy of SN 2003B, NGC 1097 had produced SNe 1992bd and 1999eu.
  These two were also SNe II, and the latter is peculiarly dim one
  (vsnet-campaign-sn 526, 530). 


  SN 2003C		(RA = 00h41m20s.91, Dec = -01d42'54".1)

    A host galaxy of SN 2003C is a ring-shaped barred-spiral galaxy
  UGC 439.  The UCB team with Keck I revealed that it was a young
  type II SN on Jan. 7 (vsnet-campaign-sn 530).

 
  SN 2003D		(RA = 09h38m53s.52, Dec = -04d51'05".1)

    A host galaxy of SN 2003D is an elliptical galaxy MCG -01-25-9
  within a group Arp 321 = HCG (Hickson Compact Groups) 40.  The UCB
  team revealed that it was subluminous SN Ia, not long after maximum
  on Jan 7.  The discovery magnitude (17.5mag) is consistent with this
  classification (vsnet-campaign-sn 530). 


  SN 2003E		(RA = 04h39m10s.88, Dec = -24d10'36".5)

    A host galaxy of SN 2003E is an edge-on spiral galaxy MCG -4-12-4,
  which makes a pair with MCG -4-12-3.  The SN is superimposed on the
  disk, so notable extinction is possible.  The expected maximum for
  typical unreddened (in the host galaxy) SN Ia is mag about 15.7
  (vsnet-campaign-sn 531).  A spectrum taken with Baade telescope on
  Jan 9.15 showed that it was a young SN II (vsnet-campaign-sn 532).


  CP Dra	        (RA = 10h15m39s.88, Dec = +73d26'05".4)

    An outburst (14.5mag) was reported by M. Simonsen on January 8.
  D. Nogami commented that during both of its outbursts in 2001
  February and 2002 April, prominent, rather coherent oscillations
  with periods of ~0.066 d, much shorter than its superhump period
  ~0.083 d, were found, only in the very early phase of the outburst
  (vsnet-campaign-dn 3280, 3284, vsnet-campaign 1362).  The Kyoto data
  on Jan. 8 clearly showed the presence of fully grown superhumps
  (~0.3 mag).  The present outburst was thus confirmed to be a
  superoutburst (vsnet-campaign-dn 3294, 3297).  The superoutburst
  continues (vsnet-campaign-dn 3306, 3316).  


  CY UMa		(RA = 10h56m57s.69, Dec = +49d41'09".1)

    H. Maehara (VSOLJ) reported the detection of superhumps (0.15
  mag).  The current outburst of CY UMa was thus confirmed to be a
  superoutburst (vsnet-campaign-dn 3282).


  HS Vir		(RA = 13h43m38s.5, Dec = -08d14'04".1)

    An outburst (14.0mag) was reported by M. Simonsen on January 8
  (vsnet-campaign-dn 3287).  It has quickly faded (vsnet-campaign-dn 3303).


  TV Col		(RA = 05h29m25s.5, Dec = -32d49'05".2)

    According to Kyoto observations, TV Col seems to have undergone an
  outburst on Jan. 8.  The object was recorded by 0.5-1.0 mag brighter
  than on other nights (vsnet-campaign-ip 96).
 

  HH Cnc		(RA = 09h16m50s.63, Dec = +28d49'43".3)

    An outburst (14.7mag) was detected by M. Simonsen on January 9
  (vsnet-campaign-dn 3298).  The observations have shown that the
  outburst is a "long" outburst, in contrast to the short one recorded
  in 1999 November.  A partial analysis of the data taken by
  R. Ishioka and K. Torii did not reveal clear presence of superhumps.
  R. Ishioka reported that the object has started fading on Jan. 12.
  Judging from the outburst behavior, T. Kato reported that HH Cnc
  seems to be an SS Cyg type dwarf nova possibly with a relatively
  short orbital period (vsnet-campaign-dn 3312).  


  SN 2003F		(RA = 05h11m33s.03, Dec = +17d03'28".4)

    A host galaxy of SN 2003F is a disturbed spiral galaxy UGC 3261.
  It is near to the Galactic plain (b = -13o), so there are several
  foreground stars superimposed on the host galaxy.  A spectrum taken
  with the Las Campanas Observatory Baade 6.5-m telescope on Jan 9.11
  revealed that it was type Ia SN a few days before maximum.  Some
  reddening within the host galaxy is suggested, as well as Galactic
  one.  The reported magnitude (16.1mag on Jan. 9) is thus
  considerably brighter than expected maximum for typical SNe Ia (mag
  about 16.7) taking account of the redshift and the Galactic
  extinction (vsnet-campaign-sn 532). 


  SN 2003G	        (RA = 02h08m28s.13, Dec = +06d23'51".9)

    A host galaxy of SN 2003G is a face-on spiral galaxy IC 208.  A
  spectrum taken with Baade telescope on Jan 9.05 revealed that it
  was a young SN IIn.  The reported magnitudes are consistent with
  that of ordinal core-collapsed SNe (vsnet-campaign-sn 532).


  SN 2003H		(RA = 06h16m25s.68, Dec = -21d22'23".8)

    A host galaxy of SN 2003H is an interacting pair NGC 2207 + IC
  2163.  The classification was not been reported on IAUC 8045.  NGC
  2207 had produced SN Ia 1975A (B=14.7 at maximum) and SN Ib(?) 1999ec
  (discovery mag about 17.9, past maximum)(vsnet-campaign-sn 532).
   

  SN 2003I		(RA = 09h27m29s.48, Dec = +03d55'45".6)

    A host galaxy of SN 2003I is a small, apparently spiral galaxy IC
  2481.  The expected maximum for typical SN Ia is mag about 16.0
  (vsnet-campaign-sn 533).


  SUPERNOVA IN NGC 4157 (RA = 12h10m57s.72, Dec = +50d28'31".8)

    K. Ayani et al. performed spectroscopy with the Bisei Astronomical
  Observatory 1.01-m telescope on January 12 and reported that this
  supernova showed a prominent H-alpha emission with a P-Cyg profile,
  which suggests that it is a normal type-II supernova
  (vsnet-campaign-sn 534). 


  SUPERNOVA IN IC 1129  (RA = 15h32m01s.91, Dec = +68d14'35".9)

    K. Ayani et al. performed spectroscopy with the Bisei Astronomical
  Observatory 1.01-m telescope on January 12 and reported that it was
  a type-Ia supernova several days before maximum light.  Adopting the
  NASA/IPAC Extragalactic Database recession velocity of 6540 km/s,
  the expansion velocity deduced from Si II (rest 635.5 nm) is about
  12100 km/s (vsnet-campaign-sn 534). 


(continuous targets)
  NSV 10934             (RA = 18h40m52s.26, Dec = -83d43'10".24)

    On January 6, the amplitude of superhumps became slightly
  smaller.  Based on observations by P. Nelson and C. Stockdale,
  T. Kato reported a superhump period of 0.07508(2) d.  The initially
  reported period (0.0743(8) d) is 1 percent small than this superhump
  period.  From these analyses, it is evident that the superhump
  timings have large O-C's during the earliest stage of the superhump
  evolution (vsnet-campaign-dn 3268, 3277).  The light curve taken by
  T. Richards on January 6 showed fast modulations (QPOs) of ~3min
  period and 0.02-0.05 mag amplitude (vsnet-campaign-dn 3271).
  Short-term modulations were also detected in the light curve taken
  by T. Richards on January 11 (vsnet-campaign-dn 3317).  In the
  data by P. Nelson on January 8, the superhumps has become slightly
  more rounded.  There was a hint of short-period oscillations (a few
  to 5 min)(vsnet-campaign-dn 3299).  On January 10, The amplitudes of
  the superhumps have decreased to ~0.2 mag.  the profile has become
  rather complex with secondary and sometimes tertiary hump features
  on the declining branch from superhump maxima.  The mean superhump
  period between Jan. 4 and 12 is 0.07485 d.  There is an undisputed
  presence of period shortening (about -1.5*10^-5)(vsnet-campaign-dn
  3300, 3310).  The superoutburst continues (vsnet-campaign-dn 3273,
  3290, 3295, 3304, 3315). 

 
  V485 Cen		(RA = 12h57m23s.30, Dec = -33d12'06".8)

    The superoutburst continues (vsnet-campaign-dn 3275).

 
  MKN 421		(RA = 11h04m27s, Dec = +38d12'32")

    It has been reported to further brighten (vsnet-campaign-blazar 295). 


  UV Gem		(RA = 06h38m44s.16, Dec = +18d16'11".5)

    T. Vanmunster commented that the object showed no superhumps
  during a long outburst in December 2000 (vsnet-campaign-dn 3264).  
  T. Kato also commented that no definite superhump was detected
  also during a long outburst in February 2001 (vsnet-campaign-dn 3266).
  A. Oksanen and M. Aho reported that the light curve on January 6
  showed 0.1mag superhumps, which indicates that the current outburst
  is a superoutburst (vsnet-campaign-dn 3267, 3269).  T. Kato reported
  that, up to Jan. 7, the superhumps were well expressed by a single
  period of 0.0966 d.  After that, The period suddenly switched to
  0.0932 d.  The difference between these periods are comparable to
  the differences between superhump periods and orbital periods.  Such
  a dramatic change (and a large change) in the superhump period is
  quite unexpected and unprecedented in SU UMa-type superhumps
  (vsnet-campaign-dn 3302, 3278, 3279, 3281, 3283, 3293).  The rate of
  decrease in superhump period is around -3*10^(-4), which is
  comparable to what we saw in KK Tel (vsnet-campaign-dn 3307, 3311).
  T. Vanmunster confirmed this trend in his observations
  (vsnet-campaign-dn 3308, 3309).  The superoutburst is now ongoing
  (vsnet-campaign-dn 3274, 3289, 3296, 3305, 3314). 


  V1208 Tau		(RA = 04h59m44s.00, Dec = +19d26'23".7)

    A. Oksanen reported that the object started rapid fading on
  January 6 (vsnet-campaign-dn 3265).


  GZ Cnc		(RA = 09h15m51s.70, Dec = +09d00'50".2)

    The outburst still continues (vsnet-campaign-dn 3276).


  DI UMa		(RA = 09h12m22s.16, Dec = +50d49'39".1)

    The Jan. 7 data by K. Tanabe indicated the start of a new
  outburst.  The object was weakly humping (superhumps?) and rising.
  28 days had past since the start of the last superoutburst in
  December (vsnet-campaign-dn 3286).  It faded on January 8, which
  indicates that it was a normal outburst (vsnet-campaign-dn 3288).

 
  BU Tau		(RA = 03h49m11s.19, Dec = +24d08'12".4)

    D. West performed photoelectric photometry and reported that the
  nearby star HD 23873 had not faded noticeably, at least on January
  13 (vsnet-campaign-be 209, vsnet-campaign 1363).

    
  V803 Cen		(RA = 13h23m44s.5, Dec = -41d44'30".1)

    It was reported to brightened again on January 5
  (vsnet-campaign-dn 3291).  The object is now in an oscillating
  bright state (vsnet-campaign-dn 3313).


  V838 Mon		(RA = 07h04m04s.816, Dec = -03d50'50".94)

    The object was reported to be possibly in 13.8mag in March 27,
  1998 (vsnet-campaign-v838mon 409), but it seems to be a nearby star
  (vsnet-campaign-v838mon 410, 411, 412, 413).


  MisV1147		(RA = 22h54m03s.78, Dec = +58d54'02".1)
  
    A new fading started on January 4.  The fading has been confirmed
  by Kyoto observations, too.  This fading seems to have been a
  shallower than those in the past.  The object was caught in rise on
  Jan. 8.  There seems to be a quasi-period of 30+ d
  (vsnet-campaign-unknown 171, 174).  D. West reported JHK magnitudes of
  MisV1147 from the 2MASS catalogue, and that the J-K color of
  MisV1147 fits nicely into the range of known YSO's while none of the
  observations have been de-reddened (vsnet-campaign-unknown 172, 173).


  V1159 Ori             (RA = 05h28m59s.52, Dec = -03d33'52".8)

    The Jan. 7 data by K. Torii showed a definite brightening and
  growth of superhumps.  The object entered its superoutbursting state
  again (vsnet-campaign-dn 3285, 3292).


  SN 2003A		(RA = 10h48m33s.86, Dec = +66d22'29".4)

    The UCB group has revealed that it was of type Ib/c, a few weeks
  after maximum on Jan. 6 (vsnet-campaign-sn 527, 528).


  eta Gem		(RA = 06h14m52s.87, Dec = +22d30'24".5)

    Recently reported observations are shown in [vsnet-campaign-ecl 56].


*** Future schedule ***

  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 ***

  Supernovas and the NASA CHIPS mission
    http://science.nasa.gov/headlines/y2003/06jan_bubble.htm?list813119
					[vsnet-campaign-dn 3270]
					[vsnet-campaign-sn 529]
  UV Gem
    Image by Nyrola team
      http://vsnet.kusastro.kyoto-u.ac.jp/pub/vsnet/DNe/UV_Gem/UVGem20030106.jpg
					[vsnet-campaign-dn 3272]
    Time-series observations by H. Maehara, see [vsnet-campaign-data 105]
    Light curves by T. Vanmunster:
      http://vsnet.cbabelgium.com
					[vsnet-campaign-dn 3308]
  GZ Cnc
    Image by Nyrola team
      http://vsnet.kusastro.kyoto-u.ac.jp/pub/vsnet/DNe/GZ_Cnc/GZCnc20030106.jpg
 					[vsnet-campaign-dn 3272]
  CY UMa
    Time-series data by H. Maehara, see [vsnet-campaign-data 103, 104].

  NSV 10934
    CCD image and NSV 10934 page:
      http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/DNe/nsv10934.html
					[vsnet-campaign-dn 3301]
  U Sco
    Preprint by K. Matsumoto et al.
      http://vsnet.kusastro.kyoto-u.ac.jp/pub/vsnet/preprints/U_Sco/usco1999.pdf
      http://vsnet.kusastro.kyoto-u.ac.jp/pub/vsnet/preprints/U_Sco/usco1999.ps.gz
      or
      http://ftp.kusastro.kyoto-u.ac.jp/pub/vsnet/preprints/U_Sco/usco1999.pdf
      http://ftp.kusastro.kyoto-u.ac.jp/pub/vsnet/preprints/U_Sco/usco1999.ps.gz
					[vsnet-campaign-nova 1148]
					   

(This summary can be cited.)	

Regards,
Makoto Uemura

VSNET Home Page

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