[vsnet-grb-info 14557] GRB 140219A: MASTER before and after GRB observational arguments of the exceptionally Dark GRB

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  15871
SUBJECT: GRB 140219A: MASTER before and after GRB observational arguments of the exceptionally Dark GRB
DATE:    14/02/21 15:42:34 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <gcncirc at observ.inetcomm.ru>

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


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


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

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

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

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

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

MASTER VWF robotic very wide field cameras (FOV=2x384 square degrees,
D=72mm, f/1.2, 1 pix = 22 arcsec) installed on  MASTER-II robotic
telescope in Tunka covered full IPN error box (Hurley et. al. GCN15864)
for very short time before and after the trigger.
Fortunatelly we have set of 26 continous  5 seconds exposure images since 
19:43:16 to 19:45:21 UT i.e.  since 196 s to 71 s before the trigger and 
set of continous  5 seconds exposure  images since 19:47:01 to 19:58:31 UT 
i.e. 3 sec after Notice Time and 29 s  after the trigger.
We haven`t found credible optical transient  with 3-sigma  upper limit
10.5m on single and about 12.0 m on coadd  (20 x 5 sec = 100 sec) images.
The Very Wide Field Cameras observation schedule with respect to GRB light 
curve (S. Golenetskii, R.Aptekar, D. Frederiks, V. Pal'shin et al., GCN 
15870)  is available at 
http://master.sai.msu.ru/static/GRB/GRB140219A_schedule.png

The first images movie available here
http://master.sai.msu.ru/static/GRB/GRB140219A_IPN_single.gif

The coadd images move available here

http://master.sai.msu.ru/static/GRB/GRB140219A_IPN_coadd1.gif
http://master.sai.msu.ru/static/GRB/GRB140219A_IPN_coadd2.gif

The same MASTER VWF robotic very wide field cameras  installed on
MASTER-II robotic telescope in Blagoveschensk also made the observations
of IPN error box  after the trigger. However the upper limit on them on
1.5m worse than in Tunka due to adverse weather conditions.

MASTER II  robotic telescope (MASTER-Net: http://observ.pereplet.ru) 
located in Tunka was pointed to the  GRB140219A  78 sec after trigger 
time  at 2014-02-19 19:47:50.943 UT by FERMI GBM trigger N414531995 in two 
polarizations. On our first (10s exposure) set we haven`t found optical 
transient  within 4 sq. degree center part of FERMI-GBM first  error-box 
(ra=10 11 55 dec=+12 14 00 radius = 32, Zhang et. al. GCN 15866)  .
The 5-sigma upper limit has been about 15.1 mag.

MASTER II  robotic telescope (MASTER-Net: http://observ.pereplet.ru) 
located in Blagoveschensk was pointed to the  GRB140219A 30 sec after 
notice time and 57 sec after trigger time at 2014-02-19 19:47:29.9 UT by 
FERMI GBM trigger .414531995 in two polarizations. On our first (10s 
exposure) set we haven`t found optical transient within 4 sq. degree 
center part of  FERMI-GBM first error-box (ra=10 11 55 dec=+12 14 00 
radius = 32 ).
The 5-sigma upper limit has been about 14.9 mag.

After IPN notice  (Hurley et. al. GCN15864) we cover full IPN and LAT 
(Guiriec et. al GCN 15867) error boxes in survey mode using 3 fields on 
two MASTER II telescope in Tunka and Blagoveschensk. The first images was 
obtained 18h 22m after trigger time at 2014-02-20 14:08:49 with upper 
limit  19.5 m in Tunka and 18.0 m in Blagoveschensk. We also haven`t found 
credible optical transient up to 20.5 m  here.

The obseravtions argue that GRB 140219A is extremely dark GRB with low 
Optical to Gamma Emission  Ratio:

F_opt/F_gamma <~  1 : 130 000

On the figure 
( http://master.sai.msu.ru/static/GRB/GRB140219A_schedule.png ) 
you can find the Gamma-Optic diagramm for the prompt 
fluence of GRBs observed by MASTER (Gorbovskoy et. al Astronomy Reports, 
Volume 57, Issue 4, pp.233-286).

The message may be cited.