GRB 131122A

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

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

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

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

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)


There are two telescope from MASTER-NET was pointed to the  GRB131122A.

MASTER II  robotic telescope (MASTER-Net: http://observ.pereplet.ru) 
located in Kislovodsk was pointed to the  GRB131122A 69 sec  after notice 
time and 76 sec after GRB time at 2013-11-22 21:26:33.898 UT in two 
polarizations. On our first (20s exposure) set we haven`t found optical 
transient  within INTEGRAL trigger N 6392 error-box (ra=10 11 02 dec=+57 
38 22 r=0.054667). The polaroids have RA and DEC orientation on this 
observatory.
The 5-sigma upper limit has been about 16.4 mag

MASTER II  robotic telescope located in Blagoveschensk was pointed to the 
GRB131122A 76 sec  after notice time and 82 sec after GRB time at 
2013-11-22 21:26:39.328 UT in two polarizations. On our first (20s 
exposure) set we haven`t found optical transient  within INTEGRAL trigger 
N 6392 error-box (ra=10 11 02 dec=+57 38 22 r=0.054667). The polaroids are 
oriented under corners 45 and 135 to the RA axis on this observatory.
The 5-sigma upper limit has been about 16.3 mag
The message may be cited.

The data reduction are continued.

The message may be cited.

D. Gotz (CEA Saclay), S. Mereghetti (IASF-Milano), E. Bozzo, C. Ferrigno, (ISDC, Versoix), and J. Borkowski (CAMK, Torun) on behalf of the  IBAS Localization Team report:

a gamma ray burst lasting about 70 s  has been detected by IBAS in the IBIS/ISGRI data at 21:25:01 U.T. on November 22.
Its refined  coordinates (J2000)  are:

  R.A.: 152.5553 deg
  DEC.: 57.7398 deg

with an uncertainty of 1.6 arc min (90% c.l.).

The burst had a fluence of about 2x10^-6 erg/cmsq in the 20-200 keV energy band, and a peak flux of 0.4 ph/cmsq/s in the same energy band over 1 s.

A plot of the light curve will be posted at http://ibas.iasf-milano.inaf.it/IBAS_Results.html

D. Xu (DARK/NBI), G.-J. Feng, X. Zhang, A. Esamdin, L. Ma (XAO) report:

We observed the IBIS/ISGRI field of GRB 131122A (Gotz et al., GCN
15510
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 ) using the 1m telescope located on Mt. Nanshan, Xinjiang, China.
We obtained 6x360s R-band frames at a mean time of 22:28:18 UT on
2013-11-22, i.e., 1.055 hr after the INTEGRAL trigger.

Visual inspect of the Intergral 1.6 arcmin error circle against DSS II
and SDSS shows that no new optical source is detected down to a
limiting magnitude of R=20.6 mag.

J. Gorosabel (IAA-CSIC/UPV-EHU), A. de Ugarte Postigo (IAA-CSIC, DARK/NBI),  D. Xu (DARK/NBI), S. Schulze (PUC, MCSS), N.R. Tanvir (U. Leicester),  O. Smirnova (NOT, U. Latvia), J. K�re (U. Oslo), E. Pakstiene (Vilnius U.), A.B. Aksnes, C. Eide, E.N. Traore, J. Joberg, L.K. Seljebotn, N. Von Huth, M. Lapadatu, R.W. Cale, M Heger (Horten videreg�ende skole) report on behalf of a larger collaboration:

We observed the field of the INTEGRAL GRB 131122A (Gorbovskoy et al., GCN 15509
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 ) with the 2.5m Nordic Optical Telescope (NOT) equipped with ALFOSC. Observations began at 00:34 UT (3.13 hr after the burst), when the field was at an airmass of ~3, and consisted of 8x180s in i-band, covering the complete INTEGRAL error box. The seeing of the combined image is around 0.9".

We do not see any obvious new source down to the limit of the SDSS i-band image to which we have compared, although we note that our frame is somewhat deeper, showing faint sources not present in the SDSS. A more precise localisation and/or deeper comparison image will be needed in order to identify a possible optical counterpart to GRB 131122A.

A. Maselli (INAF-IASFPA) and V. D'Elia (ASDC) report on behalf of the
Swift-XRT team:

We have analysed 3.0 ks of XRT data for the INTEGRAL-detected burst GRB
131122A, from 13.7 ks to 21.1 ks after the INTEGRAL trigger. The data
are entirely in Photon Counting (PC) mode. An X-ray source is detected
within the INTEGRAL error circle. Using 1383 s of PC mode data and 1
UVOT images, we find an enhanced XRT position (using the XRT-UVOT
alignment and matching UVOT field sources to the USNO-B1 catalogue):
RA, Dec = 152.54219, +57.72770 which is equivalent to:

RA (J2000): 10h 10m 10.12s
Dec(J2000): +57d 43' 39.7"

with an uncertainty of 4.8 arcsec (radius, 90% confidence). This
position is 50 arcsec from the INTEGRAL position. We cannot determine
at the present time whether the source is fading.
 
We note the presence of two DSS galaxies northbound the XRT source,
close to the XRT error circle.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00020328.

This circular is an official product of the Swift-XRT team.

A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), J. Gorosabel (IAA-CSIC/UPV-EHU),
D. Xu (DARK/NBI), S. Schulze (PUC, MCSS), N.R. Tanvir (U. Leicester), 
O. Smirnova (NOT, U. Latvia), J. K�re (U. Oslo), E. Pakstiene (Vilnius U.),
A.B. Aksnes, C. Eide, E.N. Traore, J. Joberg, L.K. Seljebotn, N. Von Huth,
M. Lapadatu, R.W. Cale, M Heger (Horten videreg�ende skole) report on 
behalf of a larger collaboration:

Further analysis of our i-band imaging from the 2.5 m NOT (Gorosabel et al., 
GCN 15512
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 ) of GRB 131122A (Gotz et al., GCN 15510
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 ), with mean epoch 
00:49 UT (3.40 hr after the burst), shows no new source within the Swift-XRT 
error box (Maselli et al., GCN 15513
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 ) down to a 3-sigma magnitude limit of 
i=23.5 (AB).

C. A. Swenson (PSU) and A. Maselli (INAF-IASFPA)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 131122A
13578 s after the INTEGRAL trigger (Gotz et al., GCN Circ. 15510
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 ).
No optical counterpart consistent with the potential XRT afterglow position
(Maselli et al., GCN Circ. 15513
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 ) is detected in the initial UVOT exposures.

Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the initial exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white            14302        20578          855         >21.3
v                20830        21061          227         >19.0
u                13578        20136         1375         >21.0

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.01 in the direction of the burst
(Schlegel et al. 1998).

A. Maselli (INAF-IASFPA) reports on behalf of the Swift-XRT team:

Swift-XRT performed a second observation of the INTEGRAL-detected burst 
GRB 131122A (Gotz et al., GCN Circ. 15510
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 ) starting on 2013 November 29, 
from 596 to 690 ks after the INTEGRAL trigger, for a total exposure of 
4.9 ks. The source reported in occasion of the first XRT observation by 
Maselli & D'Elia (GCN Circ. 15513
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 ) is now detected at a count rate of 
(1.59+/-0.69)e-3 ct/s. This value is considerably lower than 
(1.06+/-0.21)e-2 ct/s corresponding to the first observation: therefore, 
we point at this source as the afterglow of GRB 131122A.

This circular is an official product of the Swift-XRT team.