GRB 111022A

S. Immler (CRESST/GSFC/UMD), M. M. Chester (PSU), V. D'Elia (ASDC),
N. Gehrels (NASA/GSFC), C. Guidorzi (U Ferrara),
S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU),
C. B. Markwardt (NASA/GSFC), K. L. Page (U Leicester),
E. Sonbas (GSFC/USRA/Adiyaman Univ.), E. Troja (NASA/GSFC/ORAU) and
T. N. Ukwatta (MSU) report on behalf of the Swift Team:

At 16:07:04 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 111022A (trigger=506070).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 275.872, -23.668 which is 
   RA(J2000) = 18h 23m 29s
   Dec(J2000) = -23d 40' 03"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a single peak
structure with a duration of about 15 sec.  The peak count rate
was ~3000 counts/sec (15-350 keV), at ~1 sec after the trigger. 

The XRT began observing the field at 16:08:21.1 UT, 76.1 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 275.8642, -23.6724 which is equivalent to:
   RA(J2000)  = 18h 23m 27.40s
   Dec(J2000) = -23d 40' 20.6"
with an uncertainty of 6.3 arcseconds (radius, 90% containment). This
location is 27 arcseconds from the BAT onboard position, within the BAT
error circle. No event data are yet available to determine the column
density using X-ray spectroscopy. 

Swift entered the SAA shortly after detecting this burst, so there are
no prompt UVOT data products for this burst at this time. 

Burst Advocate for this burst is S. Immler (immler AT milkyway.gsfc.nasa.gov). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)

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

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

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

V.Krushinski, I.Zalozhnich, T.Kopytova, A. Popov
Ural State University, Kourovka

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

MASTER II  robotic telescope (MASTER-Net: http://observ.pereplet.ru) 
located in Kislovodsk was pointed to the  GRB111022A 29 sec  after notice 
time and 47 sec after GRB time at 2011-10-22 16:07:52 UT. On our first 
(10s exposure) set we haven`t found optical transient  within SWIFT 
error-box.
The 5-sigma upper limit has been about 16.6 mag. The object was observed 
on high (80 deg) zenit distance.
The message may be cited.

S. T. Holland (CRESST/USRA/GSFC), and
S. Immler (CRESST/USRA/GSFC)
report on behalf of the Swift/UVOT team:

GRB 111022A: Swift/UVOT Non-Detection

UVOT took a finding chart exposure of 150 seconds with the white filter
starting 815 seconds after the BAT trigger.  This field is very crowded,
but no credible afterglow candidate has been found in the initial data
products.  The 2.7' x 2.7' sub-image covers 100% of the XRT error circle.
The estimated 3-sigma upper limit is white > 20.0 mag.  No correction has
been made for the expected Galactic extinction corresponding to a reddening
of E_{B-V} =  0.66 mag.  Due to the low Galactic latitude of this burst the
extinction is highly uncertain.

H. A. Krimm (GSFC/USRA), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), S. Immler (CRESST/GSFC/UMD),
C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC),
M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU)
(i.e. the Swift-BAT team):
 
Using the data set from T-60 to T+243 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 111022A (trigger #506070)
(Immler, et al., GCN Circ. 12471
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 ).  The BAT ground-calculated position is
RA, Dec = 275.871, -23.666 deg, which is 
   RA(J2000)  =  18h 23m 29.1s 
   Dec(J2000) = -23d 39' 58.7" 
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 66%.
 
The mask-weighted light curve shows two peaks: a small peak starting
at ~T-18 sec, peaking at ~T-12 sec, merging into the main peak
at ~T-8 sec, peaking at ~T-2 sec, and ending at ~T+15 sec.
T90 (15-350 keV) is 24.7 +- 3.6 sec (estimated error including systematics).
 
The time-averaged spectrum from T-17.69 to T+18.57 sec is best fit by a power law
with an exponential cutoff.  This fit gives a photon index 1.01 +- 0.37, 
and Epeak of 64.7 +- 13.9 keV (chi squared 63.3 for 56 d.o.f.).  For this
model the total fluence in the 15-150 keV band is 2.0 +- 0.1 x 10^-6 erg/cm2
and the 1-sec peak flux measured from T-1.46 sec in the 15-150 keV band is
2.5 +- 0.2 ph/cm2/sec.  A fit to a simple power law gives a photon index
of 1.73 +- 0.08 (chi squared 76.5 for 57 d.o.f.).  All the quoted errors
are at the 90% confidence level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/506070/BA/

G. Stratta (ASDC), V. D'Elia (ASDC) and S. Immler (CRESST/GSFC/UMD)
report on behalf of the Swift-XRT team:

We have analysed 1.1 ks of XRT data for GRB 111022A (Immler  et al. GCN
Circ. 12471
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 ), from 775 s to 1.9 ks after the  BAT trigger. The data are
entirely in Photon Counting (PC) mode. The refined XRT position is RA,
Dec = 275.86481, -23.67325 which is equivalent to:

RA (J2000): 18 23 27.55
Dec(J2000): -23 40 23.7

with an uncertainty of 3.6 arcsec (radius, 90% confidence). The light
curve is consistent with a constant source of mean count rate 1.1e-01
ct/sec. A power-law fit gives an index of 0.2 (+0.6, -0.7).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.3 (+0.6, -0.5). The
best-fitting absorption column is  6.8 (+4.0, -2.7) x 10^21 cm^-2, in
excess of the Galactic value of 2.2 x 10^21 cm^-2 (Kalberla et al.
2005). The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum  is 4.4 x 10^-11 (1.0 x 10^-10) erg
cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:	     6.8 (+4.0, -2.7) x 10^21 cm^-2
Galactic foreground: 2.2 x 10^21 cm^-2
Excess significance: 2.8 sigma
Photon index:	     2.3 (+0.6, -0.5)

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00506070.

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

Myungshin Im (CEOU/Seoul National Univ), and
Yuji Urata (NCU) on behalf of EAFON

We observed GRB 111022A (Holland et al., GCN 12472
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 )
in R,I,z, and Y filters with a 1.0-m telescope at
Mt. Lemmon, Arizona. The observation started at
10-23-07:52:02 UT, or about 14.5 hrs after the BAT
alert, with total integraion of 10 min in each
filter. No credible afterglow candidate was found at
the enhanced XRT position (Beardmore et al. GCN 12478
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 ).

We thank the LOAO operator, J. Youn for his assistance
with the observation.

N. P. M. Kuin (MSSL-UCL) and S. Immler (CRESST/GSFC/UMD)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 111022A
815 s after the BAT trigger (Immler et al., GCN Circ. 12471
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 ).
No optical afterglow consistent with the XRT position (Stratta et
al, GCN Circ. 12482
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 ) is detected in the initial UVOT exposures.

The field is very crowded and the detection limits may be affected
in the white filter by the coincidence loss pattern from a
neighboring star.

Preliminary 3-sigma upper limits using the UVOT photometric system
(Poole et al. 2008, MNRAS, 383, 627) for the first finding chart (FC)
exposure and subsequent exposures are:

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

white_FC           815          965          147         >21.3
white              815         1287          186         >21.5
v                  972         1859          117         >18.7
b                 1071         1957          117         >19.9
u                 1046         1932          114         >18.9
w1                1021         1908          117         >19.5
m2                 996         1883          117         >21.0
w2                1120         1833           97         >19.0

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.66 in the direction of the burst
(Schlegel et al. 1998).

K. Tokoyoda, Y. Yatsu, Y. Aoki, R. Usui, K. Kawakami, M. Hayashi, S. Song,
and N. Kawai (Tokyo Tech)  report on behalf of the MITSuME collaboration:

We observed GRB 111022A (S. Immler et al, GCN12471
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 )
with the optical three color (g, Rc, and Ic) CCD camera attached
to the MITSuME 50 cm telescope of Akeno Observatory, Yamanashi, Japan.

The observation started on 2011-10-23 9:16:56 UT (~16.8 h after the burst).
We did not find any new point source within the Swift XRT error
circle (G. Stratta et al, GCN12482
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 ) in three bands.

Photometric results and are listed below. We used GSC2.3 catalog for
flux calibration.

T0+[day]      MID-UT     T-EXP[sec]      g'             Rc           Ic
---------------------------------------------------------------------------------
 0.71519     9:47:22        3060         >18.4       >16.5       >16.5
---------------------------------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]