[vsnet-grb-info 16675] V404 Cyg: MASTER Swift, Integral alert observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  17956
SUBJECT: V404 Cyg: MASTER Swift, Integral alert observations 
DATE:    15/06/23 12:56:37 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov at xray.sai.msu.ru>

K.Ivanov, O.Gres, N.M.Budnev, S.Yazev, O.Chuvalaev, V.A.Poleshchuk
Irkutsk State University

V.Krushinski, I.Zalozhnih,  A. Popov
Ural Federal University, Kourovka

E. Gorbovskoy, V. Lipunov,  N.Tyurina, V.Kornilov, P.Balanutsa, 
A.Kuznetsov, E.Popova, D.Kuvshinov,
Lomonosov Moscow State University, Sternberg Astronomical Institute

Rafael Rebolo, Miquel Serra, N. Lodieu, G. Israelian, L. Suarez-Andres
(The Instituto de Astrofisica de Canarias)

D.Buckley, S. Potter, A.Kniazev, M.Kotze
South African Astronomical Observatory

A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik
Kislovodsk Solar Station of the Pulkovo Observatory

V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov, A.Gabovich
Blagoveschensk Educational State University, Blagoveschensk


Hugo Levato and Carlos Saffe
Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)

Carlos Lopez, Claudio Mallamaci and Federico Podest
Observatorio Astronomico Felix Aguilar (OAFA)

MASTER-Tunka was pointed to the V404 Cyg 36 sec after notice time , 164 
sec after Swift trigger  N 643949 (Barthelmy et. al GCN #17929 )time at 
2015-06-15 18:34:23 UT. MASTER-Ural was pointed to the V404 Cyg 22 sec
after notice time , 150   sec after swift trigger N 643949 (Barthelmy et. 
al GCN #17929 ) time at 2015-06-15 18:34:09 UT.
The 5 MASTER (http://observ.pereplet.ru  , Lipunov et al.2010, Advances in 
Astronomy, vol. 2010, pp. 1-7) robotic twin telescopes every clear night 
observed V404 Cyg by Integral alerts sending ( Erik Kuulkers, ATel #7695).



  Site          DATE  UT Start         DATE  UT Finish    Exp  Duration    Polarisation

  Tunka      2015-06-15 18:34:23    2015-06-15 19:33:48   40    1.0 h         |-
2 Ural      2015-06-15 18:34:09    2015-06-15 19:42:09   10    1.1 h         /\
3 IAC       2015-06-18 00:09:07    2015-06-18 05:26:19  190    5.2 h         |-
4 Tunka     2015-06-18 14:45:47    2015-06-18 19:44:43   96    5.0 h         |-
5 Kisl      2015-06-18 18:50:29    2015-06-19 00:34:30  176    5.4 h         |-
6 SAAO      2015-06-18 22:19:33    2015-06-19 04:42:30  282    6.5 h         \/
7 Tunka     2015-06-19 14:21:47    2015-06-19 19:12:1    90    4.9 h         |-
8 Kisl      2015-06-19 18:08:38    2015-06-19 22:02:20  108    3.1 h         |-
9 SAAO      2015-06-19 21:26:05    2015-06-20 04:41:46  318    7.3 h         \/
10 Tunka    2015-06-20 16:07:32    2015-06-20 19:33:50   59    3.5 h         |-
11 Kisl     2015-06-20 17:55:38    2015-06-20 20:24:19   36    3.5 h         |-
12 SAAO     2015-06-20 21:59:20    2015-06-21 04:43:37  320    6.7 h         \/
13 Tunka    2015-06-21 19:04:51    2015-06-21 19:36:31   26    0.5 h         |-
14 SAAO     2015-06-21 21:16:36    2015-06-22 04:43:06  320    7.5 h         \/
15 Kisl     2015-06-21 21:30:56    2015-06-22 00:36:31   78    3.0 h         |-
16 SAAO     2015-06-22 21:15:28    2015-06-23 04:43:58  260    7.5 h         \/

We have more than 2400 mesuarments now; The preliminary photometry of 
MASTER-Net telescopes are available at 
http://master.sai.msu.ru/static/OT/MASTERV404.jpg

We see > 8% linear polarisation ( that corresponds to ATEL #7678 , ATEL 
#7674). We defenitely detect polatizations variability at time scale ~10 
minutes.

The Ural light curves (upper fig.) VS polarization (below) data are 
available at http://master.sai.msu.ru/static/v404syg_tu.png

The observations are continued.

The message may be cited.