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[vsnet-campaign-news 23] News from VSNET 23
*** News from VSNET ***
Re-brightening Delta Sco became brightest ever before.
A rare outburst of ES Dra and an atypically frequent outburst
of V503 Cyg were newly detected.
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 Oct. 10, 2000, as VSNET campaign circulation 528.
[Note a large part of detailed information is posted to vsnet-campaign
sub-lists].
VSNET Weekly Campaign Summary
*** Last week news ***
(new targets)
ES Dra (RA = 15h25m32s.26, Dec = +62d00'56".9)
T. Kinnunen detected a rare outburst of the unknown cataclysmic variable
ES Dra on October 6 at 13.7mag. He commented this is the first detected
one as far as he knows (vsnet-alert 5307). During his ~5 hours observation
on October 6, the magnitude is varied between 13.4 - 13.9
(vsnet-campaign-dn 190). The outburst is now ongoing, and the current
magnitude is around 13.8 (vsnet-campaign-dn 191).
Close monitorings and time-series observations are strongly encouraged
to make clear the nature of this variable star.
V503 Cyg (RA = 20h27m15s.61, Dec = +43d41'45".5)
The observations by E. Muyllaert and G. Poyner showed an outburst
of SU UMa-type dwarf nova V503 Cyg on October 8 (14.5: and 14.8mag).
It was previously reported that it shows a Z Cam like standstill at V~15.7,
and T. Kato commented that the star has apparently changed its outburst
pattern in recent years (vsnet-campaign 525). From the observation on
October 9, M. Uemura reported a possible rapid decline of this object
(vsnet-campaign 527).
Time-series observations will give hints of the current status.
(continuous targets)
IY UMa (RA = 10h43m56s.87, Dec = +58d07'32".5)
A. Oksanen, M. Moilanen, and J. Sorvari observed on IY UMa at
Nyrola observatory on September 30, and got 7 hours time-series data
which shows deep eclipses and clear superhumps (vsnet-campaign-dn 187).
M. Uemura reported an eclipse with the depth of 1.2mag from October 3
observation at Kyoto. The current magnitude is around 14.6mag
(vsnet-campaign-dn 193).
Time-series observations, particularly, including eclipses are
strongly urged.
V632 Cyg (RA = 21h35m54s.18, Dec +40d25'27".9)
The object is still in outburst. On October 3, the magnitude 14.5
was reported by G. Hanson (vsnet-campaign-dn 185).
The current outburst is a rare one. Time-series observations are
encouraged.
V452 Cas (RA = 00h52m20s.87, Dec = +53d52'17".6)
From the observation on October 9, M. Uemura reported the superoutburst
seems to be terminated (vsnet-campaign 526).
BF Ara (RA = 17h38m10s.40, Dec = -47d10'43".4)
The fading from the outburst was observed. R. Stubbings reported
<14.4 and <14.0 mag on October 4 and 8, respectively (vsnet-campaign-dn 192).
BL Lac (RA = 22h02m42.86s, Dec = +42d16'37.6")
The striking activity is still seen. The bright magnitude of 13.6
was reported on October 7 by J. Ripero (vsnet-campaign-blazer 79).
The fainter magnitude was then reported on October 8 (14.0mag
by T. Kinnunen and E. Muyllaert; vsnet-campaign-blazer 80).
Delta Sco (RA = 16h00m19s.9, Dec = -22d37'17")
The re-brightening is ongoing, and S. Otero reported that the star became
brighter than ever before (October 4, 1.86mag; vsnet-campaign-be 64).
B. Fraser also reported the brightening (V=1.87 on October 7;
vsnet-campaign-be 67). He further reported V=1.89 on October 9
(vsnet-campaign-be 68).
More observations including spectroscopy and polarymetry are urged.
PKS2005-489 (RA = 20h05m47s.4, -48d58'45".0)
The blazer PKS2005-489 is still bright. The magnitude is
around 12.2 - 12.6 (vsnet-campaign-blazer 78).
XTE J1118+480 (RA = 11h18m10s.9, Dec = +48d02'12".9)
M. Moilanen took a CCD image of XTE J1118+480 on October 7.
Using the image, M. Uemura reported the current magnitude, 18.00 mag,
is slightly brighter than its quiescent state (vsnet-campaign-xray 56).
*** General information ***
IY UMa
Data and light curve observed at Nyrola observatory can be seen at:
http://vsnet.jklsirius.fi/obs/IYUMa20000930.txt
http://vsnet.jklsirius.fi/obs/IYUMa20000930.gif
http://vsnet.jklsirius.fi/obs/IYUMa20000930.pdf
[vsnet-campaign-dn 187]
GIF animation of the eclipse presented by M. Moilanen can be seen at:
http://vsnet.ursa.fi/sirius/nytt/ccd/iyuma_animation.gif
[vsnet-campaign-dn 188]
Delta Sco
Light curve presented by S. Otero can be seen in [vsnet-campaign-be 65].
V402 And
Corrigendum:
On [vsnet-campaign 523] and [vsnet-campaign-news 22] the last
VSNET Weekly Campaign Summary about V402 And, for the position
(RA = 00h11m07s.25, Dec = +33d32'36".1)
read
(RA = 00h11m07s.25, Dec = +30d32'36".1).
^^^^
Sorry for confusion.
(This summary is reproduction free.)
Regards,
Makoto Uemura
vsnet-adm@kusastro.kyoto-u.ac.jp
Return to Daisaku Nogami
vsnet-adm@kusastro.kyoto-u.ac.jp
VSNET Home Page