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[vsnet-campaign-news 18] News from VSNET 18
*** News from VSNET ***
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.
Regards,
Taichi Kato
On behalf of the VSNET administrator team
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The continuing VSNET campaign on V368 Peg = Var63 Peg has been very
successfully ongoing, contributed by many observers from various locations
on the planet, and the object is quite nicely superhumping!
Another potentially excellent target for southern observers is AO Oct,
a well-known large-amplitude dwarf nova among cataclysmic variable
researchers, but its true nature is very little known partly because of its
low outburst frequency. Time-resolved photometry (hours long) by taking
the present opportunity is expected to finally solve the question regarding
its nature!
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).
Or, look at the list information page for more details:
http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/information.html
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The following was issued on Sep. 4, 2000, as VSNET campaign circulation 472.
[Note a large part of detailed information is posted to vsnet-campaign
sub-lists].
VSNET Weekly Campaign Summary
*** Last week news ***
(new targets)
KK Tel (RA = 20h28m37s.27, Dec = -52d18'25".1)
The suspected SU UMa-type object KK Tel started its (faint) outburst
detected by R. Stubbings at 14.8mag on August 30 (vsnet-campaign-dn 127).
Time-series observations are encouraged to clarify its nature.
V635 Cas (RA = 01h18m32s.05, Dec = +63d44'22".3)
As reported by G. Poyner on August 29, the Be X-ray transient
V635 Cas started its optical outburst (14.7mag)(vsnet-campaign-xray 45).
The observation on September 1 by T. Kinnunen shows it to be fainter
(15.1mag) (vsnet-campaign-xray 46).
Close monitorings are encouraged.
MV Lyr (RA = 19h07m15s.93, Dec = +44d01'10".7)
The VY Scl-type novalike variable MV Lyr has rapidly brightened,
which was detected on August 28 by G. Poyner. T. Kato commented
the present brightening may have been dwarf nova-type. Time-series
photometry is strongly encouraged to clarify the present state
(vsnet-campaign 463).
Time-series observations are encouraged.
60 Cyg (RA = 20h59m26s, Dec = +45d57m.5)
E. Pollmann reported the H_alpha line of this Be-star became
an absorption line, which imply the star became a normal B-star
(vsnet-campaign-be 45).
V767 Cyg (RA = 20h16m51s.95, Dec = +53d11'21".1)
As reported by T. Kinnunen, the poorly known dwarf nova V767 Cyg
experienced an outburst (15.2mag on August 28) (vsnet-campaign 464).
AO 0235+164 (RA = 02h38m39s.0, Dec = 16d37'05")
Upon notification from L. Takalo, Nyrola team observed this blazer
and confirmed its brightening. The magnitude on August 26 is V=17.56
and R=17.02 (vsnet-campaign-blazer 56).
AO Oct (RA = 21h04m59s.07, Dec = -75d21'22".5)
The large-amplitude dwarf nova AO Oct started its rare outburst
as reported by R. Stubbings on September 2 (14.4mag). T. Kato commented
The large amplitude (the object is reported to be mag 21 at minimum)
suggests an SU UMa-type dwarf nova, which may undergo a superoutburst
(vsnet-campaign 468).
Time-resolved photometry is very strongly encouraged.
LY Hya (RA = 13h31m54s.30, Dec = -29d41'01".0)
The SU UMa-type candidate LY Hya started its relatively rare
outburst as reported by R. Stubbings on September 2 (14.0mag).
Though it will be difficult to get time-series data, nightly snapshots to
follow the outburst are still highly encouraged.
V825 Her (RA = 17h18m37s.03, Dec = +41d15'50".5)
The NL-type cataclysmic variable V825 Her was reported bright (13.3mag
on September 2). More observations are needed to confirm the nature
of the brightening (vsnet-campaign 470).
HadV27 (RA = 04h48m24s.53, Dec = +41d49'45".1)
T. Kinnunen reported the brightening of this object. The magnitude
was 14.2mag on September 3 although the object was mostly at mv=14.7
in the 1999 season. T. Kato reported the object apparently coincides
with a 2MASS star, and the object is not particularly red compared to USNO
(vsnet-campaign 471).
(continuous targets)
V368 Peg (RA = 22h58m43s.5, Dec = +11d09'13")
N. Butterworth posted the time-series photometry on August 29 and 30 to
[vsnet-campaign-data 36 and 37], respectively. M. Moilanen and A. Oksanen
posted the time-series data on August 27/28 to [vsnet-campaign-data 38].
The superoutburst is now ongoing. More time-series observations
are strongly encouraged.
V1062 Cyg (RA = 21h08m12s.60, Dec = +36d49'16".6)
The fading from the outburst was observed in the last week
(vsnet-campaign-dn 128). It is now at quiescence.
V405 Vul (RA = 19h53m05s.0, Dec = +21d14'50")
T. Vaunmunster reported the fully grown superhumps with the amplitude
of 0.4mag observed on August 29/30 (vsnet-campaign 459).
J. Pietz reported his CCD observations before the current outburst
including an outburst in 1999 July/August (vsnet-campaign 466).
The final stage of the superoutburst should be observed closely.
V1141 Aql (RA = 19h37m10s.01, Dec = +02d35'59".2)
The outburst is still ongoing. The observation by M. Reszelski
shows the magnitude on September 2 to be 15.4: mag (vsnet-campaign-dn 132).
Rho Cas (RA = 23h54m22s.99, Dec = +57d29'58".7)
The fading is still ongoing. The observation by J. Ripero shows
the magnitude on August 31 to be 5.4mag (vsnet-campaign-rhocas 7).
V550 Cyg (RA = 20h05m05s.21, Dec = +32d21'21".0)
The fading from the superoutburst was observed during the last week.
The observation by T. Kinnunen shows the magnitude on August 28 to be
16.2mag (vsnet-campaign-dn 129).
Delta Sco (RA = 16h00m19s.9, Dec = -22d37'17")
The slowly fading continues (vsnet-campaign-be 48). B. Fraser reported
the observation on September 1 yielding V=2.12 (vsnet-campaign-be 47).
SN 2000cx (RA = 01h24m46s.15, Dec = +09o30'30".9)
The fading continues. The current magnitude is about 15.0mag
(vsnet-campaign-sn 61).
XTE J1118+480 (RA = 11h18m10s.9, Dec = +48d02'12".9)
M. Uemura reported the fading trend continues during the last week.
The magnitude is near that of quiescence (18.8mag) (vsnet-campaign-xray 44).
V446 Her (RA = 18h57m21s.51, Dec = +13d14'27".3)
A new outburst of this object was detected by L. T. Jensen.
The outburst magnitude is V~15.5. It is quite important to reveal
the whole outburst shape and the recurrence pattern in V446 Her
in order to understand the physics of the accretion disk in
post novae (vsnet-campaign 460).
CI Aql (RA = 18h52m03s.6, Dec = -01d28m38.9s)
The time-series photometry observed by S. Kiyota on August 25, 28, and 29
can be seen in [vsnet-campaign-data 39, 40, and 41], respectively.
PKS2005-489 (RA = 20h05m47s.4, -48d58'45".0)
This blazer was reported to be bright again (12.8mag on August 31)
(vsnet-campaign-blazer 55).
*** Future schedule ***
EF Eri (HST observation)
Researchers at Goettingen have a plan to observe this AM Her star
with HST in near future, and strongly want to know the current state
of this star. D. Nogami provides the location (RA: 03h 14m 13.21s,
Dec: -22o 35' 42.7'' (J2000)) and the sequence
(http://ftp.nofs.navy.mil/pub/outgoing/aah/sequence/sumner/eferi.seq)
in [vsnet-campaign 467].
For more detailed information, please contact with D. Nogami
(daisaku@uni-sw.gwdg.de).
V446 Her campaign (throughout this summer)
Boris T. Gaensicke organize a campaign on the post nova V446 Her (V~18).
Their aim is to obtain a *good* contiguous light curve of V446 Her that
covers 2-3 dwarf nova-like outbursts of the system, in order to compare
its outburst characteristics to those of ``normal'' dwarf novae.
They invite those of you equipped with a CCD camera to obtain a couple
of images of V446 Her per night throughout the next three months, say,
until the end of September.
For more information, please see [vsnet-campaign 325] or contact
with Boris T. Gaensicke (boris@uni-sw.gwdg.de).
In [vsnet-campaign 446].....
"Now, one and a half month later, we present a preliminary lightcurve
which you can find at
"http://alpha.uni-sw.gwdg.de/~mschrei/v446her/light.gif".
The light curve is very interesting, ......
Hence we again invite those of you equipped with a CCD camera to
obtain a couple of images of V446Her per night at least until the
end of September. Together we can rewrite the post nova scenario !!!"
*** General information ***
1432-0033
T. Vanmunster submitted a paper on this object to IBVS.
The preprint can be seen in [vsnet-preprint 10]
(http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/Mail/vsnet-preprint/msg00010.html)
[vsnet-campaign 458]
SN 1999em
D. Bishop informed an image taken by T. Puckett can be seen at:
http://vsnet.ggw.org/asras/snimages/sn1999/n1637s20.jpg
[vsnet-campaign-sn 59]
EF Eri
The location and the sequence, see [vsnet-campaign 467]
(This summary is reproduction free.)
Regards,
Makoto Uemura
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VSNET Home Page: http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/
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