GRB 110414A

D. Kuroda (OAO, NAOJ),  H. Hanayama, T. Miyaji, J. Watanabe (IAO, NAOJ),
K. Yanagisawa (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 110414A (Starling et al., GCN 11931
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 )
with the optical three color (g', Rc and Ic) CCD camera attached
to the Murikabushi 1m telescope of Ishigakijima Astronomical
Observatory.

The observation started on 10:57:59 UT (~3.3 h after the burst).
We did not find any new point source within the Enhanced XRT circle
(Osborne et al., GCN 11934
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 ) in all the three bands.

Three sigma upper limits of the OT are listed below. We used
GSC2.3 catalog for flux calibration.


T0+[day]   MID-UT   T-EXP[sec]    g'     Rc     Ic
------------------------------------------------------
0.17783    11:58:19    6180.0    >19.7  >19.8  >19.1
------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]

D. A. Kann (TLS Tautenburg), J. Elliott, and J. Greiner (both MPE Garching)
report on behalf of the GROND team:

We observed the field of GRB 110414A (Swift trigger 451343; Starling et
al., GCN 11931
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 ) simultaneously in g'r'i'z'JHK with GROND (Greiner et al.
2008, PASP 120, 405) mounted at the 2.2 m MPI/ESO telescope at La Silla
Observatory (Chile).

Observations started at 23:17 UT on April 14, 15.58 hours after the GRB
trigger, and continued until 00:38 UT. They were obtained under
challenging conditions, partially in astronomical twilight, with seeing of
1".5, average airmass of 2.1, bright moonlight and passing cirrus. From
exposures of 1379 s in g'r'i'z' and 1440 s in JHK, no source is detected
within the UVOT-enhanced XRT error circle reported by Osborne et al. (GCN
11934
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 ) or at the position of the possible i' detection (Melandri et al.,
GCN 11932
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 ) down to the following 3 sigma upper limits (all in AB):

g' > 23.0,

r' > 23.3,

i' > 22.9,

z' > 22.9,

J > 20.1,

H > 19.7 and,

K > 17.3

If the i' detection of Melandri et al. (GCN 11932
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 ) is confirmed, our
observations show the source has faded and is thus likely the afterglow of
GRB 110414A.

The given limits are derived based on calibrating the images against GROND
zeropoints and 2MASS field stars and are not corrected for the Galactic
foreground extinction corresponding to a reddening of E_(B-V) = 0.331 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 110414A (Starling et al., GCN 11931
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 )
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 2011-04-14 10:35:42 UT (~2.9 h after
the burst). We did not find any new point source within the
Enhanced XRT circle (Osborne et al., GCN 11934
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 ) in all the three
bands.

Three sigma upper limits of the OT are listed below. We used
GSC2.3 catalog for flux calibration.


T0+[day]   MID-UT   T-EXP[sec]    g'     Rc     Ic
------------------------------------------------------
0.16212    11:35:41    6180.0    >19.3  >19.2  >18.4
------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]

J. R. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), 
E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt 
(GSFC), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos 
(OSU/NASA/GSFC), R. L. C. Starling (U Leicester), 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 the recent telemetry downlink, we 
report further analysis of BAT GRB 110414A (trigger #451343) (Starling, et al., 
GCN Circ. 11931
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 ).  The BAT ground-calculated position is 
RA, Dec = 97.876, 24.349 deg which is 
   RA(J2000)  =  06h 31m 30.2s 
   Dec(J2000) = +24d 20' 56.5" 
with an uncertainty of 1.6 arcmin, (radius, sys+stat, 90% containment). The partial 
coding was 30%. 
 
The mask-weighted lightcurve shows several overlapping peaks with the first starting 
at ~T-100 sec, the main peaks at T-33, T+0, T+10, T+25, and a small peak at ~T+120 
sec, and ending at ~T+130 sec. T90 (15-350 keV) is 152.0 +- 73.2 sec (estimated error 
including systematics). 

The time-averaged spectrum from T-38.4 to T+135.6 sec is best fit by a simple 
power-law model.  The power law index of the time-averaged spectrum is 1.70 +- 0.14. 
The fluence in the 15-150 keV band is 3.5 +- 0.3 x 10^-06 erg/cm2. The 1-sec peak 
photon flux measured from T+8.62 sec in the 15-150 keV band is 1.1 +- 0.3 ph/cm2/sec. 
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/451343/BA/

T.A. Pritchard (PSU) and R. L. C. Starling (U Leicester)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 110414A
151 s after the BAT trigger (Starling et al., GCN Circ. 11931
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 ).
No optical afterglow consistent with the XRT position
(Starling et al., GCN Circ. 11931
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 ) is detected in the initial UVOT 
exposures.

Preliminary 3-sigma upper limits using the UVOT photometric system
(Poole et al. 2008, MNRAS, 383, 627) for the initial exposures are:

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

white_FC           150          300          147        >20.6
u_FC               308          558          246        >19.4
white              150         1013          334        >21.3
v                  639          831           39        >18.4
b                  565          758           39        >18.9
u                  308          733          265        >19.5
w1                 689          709           19        >18.5
m2                 664          856           39        >18.8
w2                 615          807           39        >19.2

The values quoted above are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.33 in the direction of the burst
(Schlegel et al. 1998).

R. L. C. Starling (U Leicester) reports on behalf of the Swift-XRT
team:

We have analysed 9.1 ks of XRT data for GRB 110414A (Starling  et al.
GCN Circ. 11931
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 ), from 131 s to 22.7 ks after the  BAT trigger. The
data comprise 18 s 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
Osborne et al. (GCN. Circ 11934).

The late-time light curve (from T0+5.1 ks) can be modelled with  a
power-law decay with a decay index of alpha=1.67 (+0.23, -0.22).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index	of 2.72 (+/-0.15). The
best-fitting absorption column is  5.0 (+/-0.5) x 10^21 cm^-2, in
excess of the Galactic value of 3.0 x 10^21 cm^-2 (Kalberla et al.
2005). The PC mode spectrum has a photon index of 2.32 (+0.17, -0.16)
and a best-fitting absorption column of 4.0 (+/-0.6) x 10^21 cm^-2. The
counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum  is 4.0 x 10^-11 (8.4 x 10^-11) erg cm^-2
count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:	     4.0 (+/-0.6) x 10^21 cm^-2
Galactic foreground: 3.0 x 10^21 cm^-2
Excess significance: 11.7 sigma
Photon index:	     2.32 (+0.17, -0.16)

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00451343.

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

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

Using 1551 s of XRT Photon Counting mode data and 2 UVOT
images for GRB 110414A, 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 = 97.87261, +24.36241 which is equivalent
to:

RA (J2000): 06h 31m 29.43s
Dec (J2000): +24d 21' 44.7"

with an uncertainty of 1.5 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.

A. Melandri (INAF-OAB), C. Guidorzi (U. Ferrara), C.G. Mundell  
(Liverpool JMU),
A. Gomboc, J. Japelj and D. Kopac (U. Ljubljana) on behalf of a large
collaboration report:


The 2-m Faulkes Telescope North robotically followed up GRB110414A  
(SWIFT
trigger 451343; Starling et al. GCN 11931
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 ) starting about 4 min after  
the
GRB trigger time. Observations were performed automatically with BVRi  
filters.

We do not detect any clear fading object inside the reported XRT  
position
down to a limiting magnitude of R~20.0. We do detect a faint  
uncatalogued
source, in one single SDSS-i exposure, inside the XRT error circle with
coordinates:

RA = 06:31:29.37
Dec = +24:21:45.9  (+/- 1 arcsec)

This object is not detected in subsequent SDSS-i frames. Fading is yet
to be confirmed.

This message may be cited.

R. L. C. Starling (U Leicester), A. P. Beardmore (U Leicester),
V. D'Elia (ASDC), P. A. Evans (U Leicester), J. M. Gelbord (PSU),
B. Gendre (ASDC), C. Guidorzi (U Ferrara),
S. T. Holland (CRESST/USRA/GSFC), A. Melandri (INAF-OAB),
K. L. Page (U Leicester), A. Rowlinson (U Leicester),
M. Stamatikos (OSU/NASA/GSFC), G. Stratta (ASDC) and
G. Tagliaferri (INAF-OAB) report on behalf of the Swift Team:

At 07:42:14 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 110414A (trigger=451343).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 97.876, +24.361 which is 
   RA(J2000) = 06h 31m 30s
   Dec(J2000) = +24d 21' 39"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed multiple-peaked structure
with a duration of about 50 sec.  The peak count rate
was ~400 counts/sec (15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 07:44:36.8 UT, 142.3 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
uncatalogued X-ray source with an enhanced position: RA, Dec 97.8726,
24.3624 which is equivalent to:
   RA(J2000)  = 06h 31m 29.42s
   Dec(J2000) = +24d 21' 44.7"
with an uncertainty of 2.3 arcseconds (radius, 90% containment). This
location is 12 arcseconds from the BAT onboard position, within the BAT
error circle. This position may be improved as more data are received;
the latest position is available at http://www.swift.ac.uk/sper. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of 3.05
x 10^21 cm^-2 (Kalberla et al. 2005). 

The initial flux in the 2.5 s image was 4.11e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of nominal 250 seconds with the U filter
starting 308 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. Data from the 2.7'x2.7' sub-image are
not available at this time. 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 18.0 mag. No correction has been made for the expected
extinction corresponding to E(B-V) of 0.33. 

Burst Advocate for this burst is R. L. C. Starling (rlcs1 AT star.le.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.)