GRB 111215A

S. R. Oates (UCL-MSSL), S. D. Barthelmy (GSFC),
W. H. Baumgartner (GSFC/UMBC), D. N. Burrows (PSU),
J. R. Cummings (NASA/UMBC), V. D'Elia (ASDC), C. Guidorzi (U Ferrara),
S. T. Holland (CRESST/USRA/GSFC), H. A. Krimm (CRESST/GSFC/USRA),
N. P. M. Kuin (UCL-MSSL), V. Mangano (INAF-IASFPA),
F. E. Marshall (NASA/GSFC), C. J. Mountford (U Leicester),
P. T. O'Brien (U Leicester), J. P. Osborne (U Leicester),
C. Pagani (U Leicester), K. L. Page (U Leicester),
D. M. Palmer (LANL), P. Romano (INAF-IASFPA), M. H. Siegel (PSU),
R. L. C. Starling (U Leicester), T. N. Ukwatta (MSU) and
B.-B. Zhang (PSU) report on behalf of the Swift Team:

At 14:04:08 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 111215A (trigger=509717).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 349.548, +32.475 which is 
   RA(J2000) = 23h 18m 12s
   Dec(J2000) = +32d 28' 32"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  As is usual for an image trigger, the BAT light 
curve shows nothing of note. 

The XRT began observing the field at 14:11:06.0 UT, 417.7 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 349.5578, 32.4938 which is equivalent to:
   RA(J2000)  = +23h 18m 13.87s
   Dec(J2000) = +32d 29' 37.7"
with an uncertainty of 5.3 arcseconds (radius, 90% containment). This
location is 73 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. 

The initial flux in the 2.5 s image was 1.51e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 426 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of
the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. 
The 8'x8' region for the list of sources generated on-board covers 100% of the
XRT error circle. The list of sources is typically complete to about 18 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.06. 

Burst Advocate for this burst is S. R. Oates (sro AT mssl.ucl.ac.uk). 
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.)

L.P. Xin,  J.Y. Wei, Y. L. Qiu,  J. Wang, J.S. Deng, 
C. Wu, X. H. Han on behalf of EAFON report:

We began to observe GRB 111215A ( Oates  et al., GCN 12681
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 )
with Xinglong TNT telescope at 14:20:23  (UT), about 16.25 min  after 
the burst.  30 R-band images  were obtained. The exposure time is 60 sec 
for each frame.

No new source was detected in the combined R band image within 
the errorbox of XRT position. The upper limit was estimated 
to be about 18.0  mag derived from USNO B1.0 R2 mag,
at the mean time of 32.75 min after the burst. 

This message may be cited.

For more information about Xinglong GRBs Follow-up
observations, please visit the website:
http://www.xinglong-naoc.org:8080/grb/index.html"

D. Xu (WIS/NAOC), X.-H. Zhao (YNAO), J.-R. Mao (KASI/YNAO), J.-M. Bai
(YNAO) report:

We observed the field of GRB 111215A (Oates et al., GCN 12681
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 ) at the
2.4m Gao-Mei-Gu (GMG) telescope equipped with YFOSC. Observations
started at 14:26:44 UT (i.e., 22.6 mins after the burst) and a series
of R-band images (totally 1700s exposure) were obtained in a seeing of
~2.8".

No optical source was detected within the XRT error circle (ref., GCN
12681
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 ) to a 3sigma limit of R~22.8 mag, calibrated with nearby USNO B1
stars.

The image trigger mode of this burst and the above R-band upper limit
might indicate high-redshift. NIR follow-ups are encouraged.

We thank the GMG staff, especially Y.-X. Xin, D.-Q. Wang, and Y.-D.  
Lang for performing the observations.

[GCN OPS NOTE(15dec11): Par author's request, the last sentence was added.]

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

We observed GRB 111215A (S. R. Oates et al, GCN12681
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 ) with the
optical three color (g, Rc, and Ic) CCD cameras attached to the MITSuME
50 cm telescope of Akeno Observatory, Yamanashi, Japan.

We started the observation 387 sec after the BAT trigger
from 2011-12-15 14:10:35 UT.  And we did not find any new point source
within the XRT error circle (S. R. Oates et al, GCN12681
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 ) in the three bands.
The results of photometry (3sigma upper limits) are listed below.

#The photon flux were calibrated against GSC2.3 catalog.

T0+[sec]      MID-UT     T-EXP[sec]       g'              Rc           Ic
----------------------------------------------------------------------------------------
    387         14:33:55        2700          > 19.3      > 19.4      > 19.0
----------------------------------------------------------------------------------------
T0+ : Elapsed time after the burst [sec]
T-EXP: Total Exposure time [sec]

S. B. Pandey, Rupak Roy, Brajesh Kumar and R. K. S. Yadav (ARIES,
NainiTal, India, on behalf of larger Indian GRB collaboration).

GRB 111215A field, localized by Swift (Oates et al., GCN 12681
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 ), was
observed with 1.04m telescope at ARIES NainiTal starting 14:22:30 UT (~18
minutes after the burst) in R_c pass-band with an exposure time of 300 sec
each.

Photometry of the co-added R_c frame (300 sec x 6) in comparison to nearby
USNO stars did not detect any new source within the XRT error-box down to a
limiting magnitude of ~ 21.5 mag.

This message may be cited.

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

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

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

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

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

3 Robotic telescopes MASTER II was pointing to the GRB111215A (Oates et
al., GCN CIRCULAR NUMBER:  12681). Two very wide field cameras
was observed Swift error box before, during and after GRB trigger time.

MASTER II  robotic telescope (MASTER-Net: http://observ.pereplet.ru)
located in Tunka(Siberia) was pointed to the  GRB111215A 26 sec s after
notice time and 381 sec after GRB time at 2011-12-15 14:10:29.44 UT in two  
polarizarions.  On our first (80s exposure) set we haven`t found optical
transient  within SWIFT error-box (ra=23 18 12 dec=+32 28 47 r=0.050000).
  The 5-sigma upper limit has been about 18.8 mag

  MASTER II  robotic telescope
located in MASTER-Amur was pointed to the  GRB111215A 214 sec s after
notice time and 567 sec after GRB time at 2011-12-15 14:13:35.289 UT in
two diagonal  polarizarions. On our first (110s exposure) set we haven`t
found optical transient  within SWIFT error-box.
The 5-sigma upper limit has been about 17.5 mag

MASTER II  robotic telescope
located near Kislovodsk was pointed to the  GRB111215A 7655 sec s after
notice time and 8007 sec after GRB time at 2011-12-15 16:17:35.91 UT
(time delay is so long  due to weather conditions). On
our first (180s exposure) set we haven`t found optical transient  within
SWIFT error-box.
The 5-sigma upper limit has been about 18.1 mag

Two   MASTER Very Wide Field Cameras located at Tunka
(D=68 mm, 420 square degrees, 11 Mpx) was observed  GRB error box
with 5 s exposure  befoure, during and after GRB Trigger Time
without time gap between images.

Our unfiltered images are calibrated relative to Tycho stars (V).
The magnitude limit of the each emage is  12.0 m at the edge of FOW.

We do not detect OT.
The video from MASTER VWF cameras is available at
http://master.sai.msu.ru/static/GRB111215/grb111215.html

The reduction is continuated.

  The message may be cited.

F. Aceituno (OSN,IAA-CSIC), A.J. Castro-Tirado, A. de Ugarte Postigo, J.C. Tello, J. Gorosabel (IAA-CSIC), report on behalf of a larger collaboration:

"We have observed the field of GRB 111215A (Oates et al., GCN 12681
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 ) with the 1.5m telescope at Observatorio de Sierra Nevada (OSN), Granada, Spain. The data were acquired in the I-band on Dec 15.7537 -- Dec. 15.8168 UT (starting ~4 hour post burst), with a total exposure time of 18x300s. A preliminary analysis reveals no object brighter than I=21.7 in the XRT error circle. The calibration was carried out using the USNO B1.0 catalogue."

S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC),
E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),   
C. B. Markwardt (GSFC), S. R. Oates (UCL-MSSL), D. M. Palmer (LANL),
T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (OSU),
J. Tueller (GSFC), T. N. Ukwatta (MSU)
(i.e. the Swift-BAT team):

Using the data set from T-239 to T+963 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 111215A (trigger #509717)   
(Oates, et al., GCN Circ. 12681
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 ).  The BAT ground-calculated position is
RA, Dec = 349.582, 32.440 deg, which is
   RA(J2000)  =  23h 18m 19.6s
   Dec(J2000) = +32d 26' 24.2"
with an uncertainty of 4.2 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 46%.
   
The mask-weighted light curve shows the emission starting at ~T-110 sec,
although we note that the burst location came into the BAT FoV around
T-200 sec, so we can not make any statement about possible earlier emission.
There are a few overlapping peaks at ~T+20 sec, ~T+170 sec, and T+300 sec,
the the lightcurve slowly decreases back to baseline around T+1500 sec.
T90 (15-350 keV) is 796 +- 250 sec (estimated error including systematics).
   
The time-averaged spectrum from T-116.4 to T+960.1 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.70 +- 0.18.  The fluence in the 15-150 keV band is 4.5 +- 0.5 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+216.35 sec in the 15-150 keV band
is 0.5 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.
   
The duration of this burst is very long, and we note that this location is
well off the Galactic Plane (lon=101,lat=-26).  We can not rule out
a non-GRB source for this event.
   
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/509717/BA/

A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 2785 s of XRT Photon Counting mode data and 4 UVOT
images for GRB 111215A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 349.55538, +32.49401 which is equivalent
to:

RA (J2000): 23h 18m 13.29s
Dec (J2000): +32d 29' 38.4"

with an uncertainty of 1.4 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.

N. Kawai, M. Morii (Tokyo Tech), H. Negoro (Nihon U.),  M. Serino (RIKEN),
K. Sugimori, R. Usui, T. Toizumi, Y. Aoki, S. Song (Tokyo Tech),
S. Ueno, H. Tomida, M. Kohama, M. Ishikawa (JAXA),
T. Mihara, M. Sugizaki, S. Nakahira, T. Yamamoto, T. Sootome, M. Matsuoka (RIKEN), 
A. Yoshida, K. Yamaoka (AGU),
H. Tsunemi, M. Kimura, H. Kitayama (Osaka U.), 
M. Nakajima, F. Suwa, M. Asada, H. Sakakibara (Nihon U.), 
Y. Ueda, K. Hiroi, M. Shidatsu (Kyoto U.),
Y. Tsuboi, T. Matsumura, K. Yamazaki (Chuo U.)
M. Yamauchi, Y. Nishimura, T. Hanayama (Miyazaki U.) 
report on behalf of the MAXI team:

MAXI/GSC observed the position of GRB 111215A
(swift trigger=509717, Oates et al. GCN #12681
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 )
at 13:12 and 14:44 on December 5, 2011 (UT), 
52 min before and 40 min after the trigger time.

The source was marginally detected as follows: 

Time    2-4 keV          4-10 keV
13:12   4 +-  7 mCrab  52 +- 19 mCrab
14:44  16 +- 10 mCrab  41 +- 19 mCrab

(uncertainties are 1-sigma statistical errors) 

If this detections are true it implies that the emission of GRB 111215A lasted
for more than 1.5 hours. Together with the long trigger timescale (320 s)
by Swift BAT, unusual for a GRB, we suggest that it may be a
non-GRB X-ray transient, such as an X-ray binary, AGN, or extragalactic TDE.

Multiwavelength follow-up observations are strongly encouraged.

A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), O.M.
Littlejohns (U. Leicester), A. Melandri (INAF-OAB), B. Sbarufatti
(INAF-OAB/PSU), G. Stratta (ASDC), J.A. Kennea (PSU), M.C. Stroh (PSU),
D.N. Burrows (PSU) and S.R. Oates report on behalf of the Swift-XRT
team:

We have analysed 7.1 ks of XRT data for GRB 111215A (Oates  et al. GCN
Circ. 12681
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 ), from 407 s to 59.3 ks after the  BAT trigger. The data
comprise 2.2 ks in Windowed Timing (WT) mode (the first 9 s were taken
while Swift was slewing) with the remainder in Photon Counting (PC)
mode. The enhanced XRT position for this burst was given by Beardmore
et al. (GCN. Circ 12690).

The late-time light curve (from T0+5.9 ks) can be modelled with an
initial power-law decay with an index of alpha=2.13 (+0.13, -0.12),
followed by a break at T+14.6 ks to an alpha of 1.21 (+0.15, -0.16).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index	of 1.847 (+/-0.027). The
best-fitting absorption column is  4.10 (+/-0.12) x 10^21 cm^-2, in
excess of the Galactic value of 5.6 x 10^20 cm^-2 (Kalberla et al.
2005). The PC mode spectrum has a photon index of 2.14 (+/-0.12) and a
best-fitting absorption column of 3.2 (+0.5, -0.4) x 10^21 cm^-2. The
counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum  is 3.9 x 10^-11 (6.8 x 10^-11) erg cm^-2
count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:	     3.2 (+0.5, -0.4) x 10^21 cm^-2
Galactic foreground: 5.6 x 10^20 cm^-2
Excess significance: 10.2 sigma
Photon index:	     2.14 (+/-0.12)

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00509717.

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

S. R. Oates (MSSL-UCL) reports on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 111215A
426 s after the BAT trigger (Oates et al., GCN Circ. 12681
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 ).
No optical afterglow consistent with the XRT position
(Beardmore et al., GCN Circ. 12690
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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 first
finding chart (FC) exposure and subsequent exposures are:

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

white_FC           426          576          147         >21.7
white              426        19036          645         >22.0
v                  732        13257          608         >20.1
b                  657        18972         1198         >21.6
u                  632         6983          313         >20.7
w1                 608        22616          593         >20.6
m2                 583         6572          313         >20.7
w2                 708        12928         1260         >21.3

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.06 in the direction of the burst
(Schlegel et al. 1998).

D. Kuroda, K. Yanagisawa, Y. Shimizu, H. Toda (OAO, NAOJ),
S. Nagayama (NAOJ), M. Yoshida (Hiroshima), K. Ohta (Kyoto)
and N. Kawai(Tokyo Tech)
report on behalf of the MITSuME collaboration:

We observed the field of GRB 111215A (Oates et al., GCNC 12681)
with the optical three color (g', Rc and Ic) CCD camera attached
to the MITSuME 50cm telescope of Okayama Astrophysical Observatory.

The observation started on 2011-12-15 14:10:37 UT (~6.5 min after
the burst). We did not find any new point source within the enhanced
XRT circle (Beardmore et al., GCNC 12690) in all the 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
------------------------------------------------------
0.03242    14:50:49    3420.0    >18.6  >19.0  >18.7
--------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]

P. D'Avanzo, A. Melandri, S. Covino (INAF/OABr), L. A. Antonelli, V. D'Elia (INAF/OAR and ASDC/ASI), E. Palazzi (INAF/IASF Bo), D. Fugazza (INAF/OABr), G. Tagliaferri (INAF/OABr), and S. D. Vergani (INAF/OABr), report on behalf of the CIBO collaboration:

We observed the field of GRB 111215A (Oates et al., GCN 12681
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 ) with the TNG telescope located in the Canary Islands. We secured 30 min Ks-band imaging with the NICS instrument, with a mean time Dec 15.845 UT (6.30 hr after the GRB trigger).

Within the UVOT-enhanced XRT error circle (Beardmore et al., GCN 12690
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 ), we detect no new source down to a limiting magnitude K > 19 (Vega, calibrated against the 2MASS catalog).

Taking the X-ray flux at the time of the TNG observation from the UK X-ray light curve repository (http://www.swift.ac.uk/xrt_curves/00509717/), we compute a broad-band optical-to-X-ray spectral index beta_OX < 0.25, which classifies GRB 111215A as dark according to the widely adopted definition of Jakobsson et al. (2004, ApJ, 617, 21). The non detection in the K band, coupled with the significant absorption in the X-ray spectrum (Beardmore et al., GCN 12692
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 ), suggests a highly extinguished, rather than a high redshift, event. Deep observations to look for a host galaxy are encouraged.

We acknowledge excellent support from the observing staff at the TNG, especially Marco Pedani and Giovanni Mainella.

N. R. Tanvir, K. Wiersema (U. Leicester), A. Melandri (INAF-OAB),
T. Kruehler, J. Fynbo (DARK), A. J. Levan (U. Warwick), C. G. Mundell,
R. J. Smith (LJMU), C. Guidorzi (U. Ferrara), D. Xu (WIS) and
I. Skillen (ING) report:

We imaged the field of GRB111215A (Oates et al. GCN12681
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 ) using the
WHT, the LT and the NOT, all on La Palma, on the night of 2011-Dec-15 (UT).
Seeing conditions were rather poor (FWHM~2"), and no counterpart was
located to the following 3-sigma limits at the given mid-times post-burst:

WHT/LIRIS (calibrated against 2MASS)
K>19.3 at 4hr 55m
J>19.4 at 5hr 15m

LT/RATCam (calibrated against SDSS)
z'>21.7 at 6hr 50m

NOT/StanCam (calibrated against SDSS)
z'>22.5 at 6hr 50m

The K-band limit is consistent with that provided by D'Avanzo et
al. (GCN12695
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 ) from the TNG, and confirms this source to be dark even
in the infrared.

We are grateful to Ilia Ilyin for assistance in obtaining the NOT observations.

S. B. Cenko (UC Berkeley), P. E. Nugent (LBNL / UC Berkeley), and S. R.
Kulkarni (Caltech) report on behalf of a larger collaboration:

We have examined pre-outburst imaging of the location of GRB111215A (Oates
et al., GCN12681
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 ) obtained over the last 7 years with the Palomar 48 inch
Oschin Schmidt telescope.

As part of the Palomar Transient Factory, we have imaged the location of
GRB111215A regularly (every ~ 3-4 nights) over the time period from June -
October 2011.  Coadding all images of this location, no sources are
detected within the XRT error circle (Beardmore et al., GCN12690
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 ) to a
limiting magnitude of r' > 22.8 mag (calibrated with respect to several
nearby field stars from SDSS).  Furthermore, no previous outbursts are
detected in any individual frames over this period, to a typical limiting
magnitude of r' > 20.5 mag.

In addition, we co-added 117 archival images from the DeepSky* project at
Palomar Observatory obtained over the time period from 2004-2008 as part
of the Palomar-Quest Consortium.  No source is detected at the XRT
position to a limiting magnitude of i' > 22.6 mag.

* http://supernova.lbl.gov/~nugent/deepsky.html

V. Rumyantsev, N. Pit' (CrAO), A. Volnova (SAI MSU),  M. Andreev (Terskol 
Branch of INASAN), N. Parakhin, (IC AMER, NASU), A. Pozanenko (IKI) report 
on behalf of larger GRB follow-up collaboration:

We observed the field of GRB  111215A (Oates  et al. GCN 12681
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 ) with AZT-11 
telescope of CrAO observatory starting on Dec.15  (UT) 15:18:22  under mean 
seeing (FWHM) of 3.1 arsces and with Zeiss-600 telescope of Mt.Terskol 
observatory starting on Dec.15  (UT) 21:03:45   under mean seeing (FWHM) of 
1.8 arsces . We took several frames  in R-band. Within enhanced Swift-XRT 
position (Beardmore et al. GCN  12690
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 ) we do not detected any optical 
source. A photometry is based on the nearby USNO-B1.0 stars (R2):

T_start UT  T0+        Filter, Exposure, OT,  uplim (3 sigma)
                  (mid, d)            (s)

15:18:22  0.0738       R     21x180    n/d     21.0
21:03:45  0.3113       R     51x60      n/d     19.3

Authors: 
A. Horesh (Caltech), J. Carpenter (Caltech), A. Corsi (Caltech), A. Zauderer (CfA), S. R. Kulkarni (Caltech), E. Berger (CfA), D. A. Frail (NRAO), S. B. Cenko (UC Berkeley), D. Perley (Caltech)


On 2011 December 17.04 UT (1.46 days after burst) we observed GRB111215A (Oates et al., GCN12681
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 ) with CARMA at 93 GHz. We detected the source at RA=23:18:13.32, Dec=+32:29:39.09 (J2000). This position is consistent with the Swift-XRT position. 
 
We continue to monitor the source with CARMA.

A. Zauderer and E. Berger (Harvard) report on behalf of a larger
collaboration:

"We observed the position of GRB 111215A (GCN 12681
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 ) with the EVLA at 
21.8 GHz beginning on 2011 Dec 18.93 UT (3.35 days after the burst).  We 
report a radio counterpart consistent with the Swift-XRT position (GCN 
12690
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 , http://www.swift.ac.uk/xrt_positions) and the reported CARMA 
detection by Horesh et al. (GCN 12710
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 ).

The position of the detected EVLA radio source is (J2000):
RA  =   23:18:13.310 +/- 0.001
Dec =  +32:29:39.18 +/- 0.01

Follow-up observations are ongoing."

S. B. Cenko, J. S. Bloom, J. M. Silverman, A. N. Morgan (UC Berkeley), D.
A. Perley (Caltech), A. Cucchiara, J. X. Prochaska (UCSC / UCO Lick), A.
V. Filippenko (UC Berkeley), and P. E. Nugent (LBNL / UC Berkeley) report
on behalf of a larger collaboration:

We have imaged the field of GRB111215A (Oates et al., GCN 12681
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 ) with the
Low-Resolution Imaging Spectrometer (LRIS) mounted on the 10 m Keck I
telescope beginning at 5:12 UT on 2012 Dec 26 (~ 10.6 days after the Swift
BAT trigger).  Near the position of the radio and mm counterpart (Horesh
et al., GCN 12710
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 ; Zauderer et al., GCN 12711
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 ), we detect a faint source
with coordinates:

	RA: 23:18:13.29      Dec: +32:29:38.8  (J2000.0)

Astrometric calibration was performed with respect to several 2MASS point
sources in the field of view, and we estimate an uncertainty of ~ 200 mas
in each coordinate.  We measure a magnitude for this object of R ~ 25.2
(referenced to nearby point sources from the Sloan Digital Sky Survey).

Using the sky density of objects of this brightness (Hogg et al., 1997,
MNRAS, 288, 404), we estimate the probability of chance alignment (e.g.,
Bloom et al., 2002, AJ, 123, 1111) to be relatively small (<~ 1%).  We
therefore consider it likely that this object is associated with
GRB111215A.

A second, fainter source is visible ~ 1.5" NE of the radio position.  The
relation of this source to GRB111215A is not clear at the moment, as the
probability of chance coincidence at this radius and brightness is not
negligible.