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[vsnet-campaign-news 81] News from VSNET 59
*** News from VSNET ***
AL Com experienced a sudden dip during the current outburst,
and then, rapidly recovered.
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 June. 18, 2001, as VSNET campaign circulation 980.
[Note a large part of detailed information is posted to vsnet-campaign
sub-lists].
VSNET Weekly Campaign Summary
*** Last week news ***
(new targets)
SN 2001cn (RA = 18h46m17s.84, Dec = -65d45'41".8)
SN 2001cn was discovered by R. Chassagne on June 11.95 at mag
about 14.8, and remains at nearly the same magnitude until June
13.531 when R. Sanrallo confirmed it. The SN position is about
2" west and 18" south of the nucleus of the face-on spiral galaxy
IC 4758. The reported magnitude is somewhat brighter than the
expected maximum (V magnitude 15.4) of typical SN Ia for this
galaxy's recession velocity. It would possibly be caused that
the discoverer (and also confirmer) used ST-7E, which is sensitive
for blue light, and USNO-A2.0 r magnitude for the comparison stars.
SNe in the early stage is usually bluer than the surrounding
comparison stars, so the blue-sensitive CCD (without filter) will
catch more photons from the young SN than stars whose r magnitude is
comparable with that of SN. It is possible, however, that this SN is
intrinsically bright (vsnet-campaign-sn 208).
RX J0944.5+0357 (RA = 09h44m31s.8, Dec = +03d58'06")
P. Schmeer reported that this dwarf nova is currently undergoing
its second ever recorded outburst. The only previously recorded
outburst was detected by T. Watanabe on 2001 Jan 4.740 UT at mv= 13.2
(vsnet-campaign 977).
IY UMa (RA = 10h43m56s.87, Dec = +58d07'32".5)
P. Schmeer detected an outburst of the eclipsing SU UMa type
dwarf nova, IY UMa at about 14mag on June 14 (vsnet-campaign 976).
T. Kato noticed the suggested supercycle indicates the current
outburst is a superoutburst (vsnet-campaign 978). The object
has further brightened, which support it is a genuine superoutburst
(vsnet-campaign-dn 906, 907). The superoutburst still continues
(vsnet-campaign-dn 908, 911).
BL Lac (RA = 22h02m42.86s, Dec = +42d16'37.6")
An outburst of BL Lac (13.7mag) was detected on June 8
(vsnet-campaign-blazar 204). The bright and active state continues
(vsnet-campaign-blazar 205).
QW Ser (RA = 15h26m13s.99, Dec = +08d18'03".8)
M. Simonsen reported an outburst of QW Ser at 13.7mag on June 18
(vsnet-campaign-dn 913).
(continuous targets)
SBS 1017+533 (RA = 10h20m26s.65, Dec = +53d04'32".6)
The fading from the superoutburst was reported on June 10
(vsnet-campaign-dn 896).
V660 Her (RA = 17h42m07s.3, Dec = +23d47'37".3)
The superoutburst continued until around June 10
(vsnet-campaign-dn 897, 903).
V1548 Aql (RA = 19h07m28s.42, Dec = +11d44'45".8)
The slow brightening continues (vsnet-campaign-nova 343, 347).
The current magnitude is about 13.2mag.
AL Com (RA = 12h32m25s.90, Dec = +14d20'42".5)
The superoutburst is still ongoing (vsnet-campaign-dn 895, 912).
A temporal dip was observed since June 11 as reported by R. Ishioka
(vsnet-campaign-dn 898). J. Pietz reported recovering from the
dip on June 13 (vsnet-campaign-dn 900, 901, vsnet-campaign 974).
R. Novak also confirmed the dip and recovering and performed
successful time-series observations (vsnet-campaign-dn 904,
vsnet-campaign 975).
V803 Cen (RA = 13h23m44.5s, Dec = -41d44'30".1)
P. Williams reported an outburst of V803 Cen at 13.6mag on
June 17 (vsnet-campaign-dn 914).
IX Dra (RA = 18h12m32s.2, Dec = +67d04'41")
The observation at Kyoto on June 11 confirms that the outburst
since the last week was a genuine superoutburst. This established
that IX Dra is a new member of ER UMa stars (vsnet-campaign 972).
The superoutburst continued at least until June 12
(vsnet-campaign-dn 894, 899, 902).
CR Boo (RA = 13h48m55s.42, Dec = +07d57'30".3)
The object is again brightening to 13.8mag on June 13
(vsnet-campaign-dn 910).
*** Future schedule ***
CV conference at Goettingen, 5-10 August 2001
[vsnet-announce 15, 20]
Elizabeth and Frederick White Workshop
AGN variability across the Electromagnetic Spectrum
25 - 29 June 2001 Sydney, Australia
For more information, see [vsnet-campaign-blazar 168].
Two Years of Science with Chandra *
* This meeting will also be the 12th Annual Maryland Astrophysics
Conference
September 5-7, 2001
For more information, see [vsnet-campaign-xray 66]
*** General information ***
AL Com
The VSNET page of 2001 outburst has been updated.
http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/DNe/alcom0105.html
[vsnet-campaign 973, 979]
Images and light curves presented by R. Novak
http://ada.astronomy.cz
http://codel.astronomy.cz/ada/stars/alcom/alcom.html
[vsnet-campaign-dn 904]
IY UMa
eclipse ephemeris, see [vsnet-campaign-dn 905, 909]
Period of Be stars
S. Otero reports his observations of several Be stars and suggested
or confirmed their periods; see [vsnet-campaign-be 133, 134].
(T. Ganded comments; [vsnet-campaign-be 135])
(This summary can be cited.)
Regards,
Makoto Uemura
vsnet-adm@kusastro.kyoto-u.ac.jp
Return to Daisaku Nogami
vsnet-adm@kusastro.kyoto-u.ac.jp
VSNET Home Page