GRB 130627A

S. R. Oates (UCL-MSSL), V. D'Elia (ASDC), P. A. Evans (U Leicester)
and A. Y. Lien (NASA/GSFC/ORAU) report on behalf of the Swift Team:

At 08:55:03 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 130627A (trigger=559132).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 184.445, -37.086 which is 
   RA(J2000) = 12h 17m 47s
   Dec(J2000) = -37d 05' 09"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a multi-peaked
structure with a duration of about 30 sec.  The peak count rate
was ~1000 counts/sec (15-350 keV), at ~3 sec after the trigger. 

Due to an observing constraint, Swift will not slew until T0+46.0
minutes. There will be no XRT or UVOT data until this time. 

Burst Advocate for this burst is S. R. Oates (samantha.oates AT 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.)

S. R. Oates & M. De Pasquale (UCL-MSSL) report on behalf of the Swift/UVOT Team:

UVOT took a finding chart exposure of 150 seconds with the White filter of GRB 130627A (trigger= 559132)
starting 2979 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 25%
of the BAT 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 BAT error circle. The list of sources is typically complete down to about 18
mag. No correction has been made for the expected extinction corresponding to
E(B-V) of 0.09.

J.A. Kennea (PSU), G. Tagliaferri (INAF-OAB), S. Campana (INAF-OAB),
P.A. Evans (U. Leicester), J.P. Osborne (U. Leicester) and D.N. Burrows
(PSU) report on behalf of the Swift-XRT team:

The XRT began observing the field of GRB 130627A at 09:44:39.3 UT,
2975.9 seconds after the BAT trigger. Using promptly downlinked data we
find an uncatalogued X-ray source located at RA, Dec 184.41689,
-37.08615 which is equivalent to:
   RA(J2000)  = 12h 17m 40.05s
   Dec(J2000) = -37d 05' 10.1"
with an uncertainty of 3.6 arcseconds (radius, 90% containment). This
location is 80 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 in excess of the Galactic value (7.95 x
10^20 cm^-2, Kalberla et al. 2005), with an excess column of 3.9
(+2.51/-2.13) x 10^21 cm^-2 (90% confidence).

D.Byrne (UCD) reports on behalf of the Fermi GBM Team:

"At 08:55:05.93 UT on 27 June 2013, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 130627A (trigger 394016108 / 130627372),
which was also detected by the Swift/BAT (Oates et al. 2013, GCN 14933
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 ).
The GBM on-ground location is consistent with the Swift position.

The GBM light curve shows/consists of a multiple pulses,
with a duration (T90) of about 28 s (50-300 keV).
The time-averaged spectrum from T0-13.31 s to T0+14.34 s is
adequately fit by a power law function with an exponential
high-energy cutoff.  The power law index is -1.4 +/- 0.2 and
the cutoff energy, parameterized as Epeak, is 86 +/- 25 keV.

The event fluence (10-1000 keV) in this time interval is
(1.334 +/- 0.185)E-06 erg/cm^2. The 1.024-sec peak photon flux measured
starting from T0-1.28 s in the 10-1000 keV band
is 2.17 +/- 0.25 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."

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

Using 4487 s of XRT Photon Counting mode data and 11 UVOT
images for GRB 130627A, 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 = 184.41524, -37.08699 which is equivalent
to:

RA (J2000): 12h 17m 39.66s
Dec (J2000): -37d 05' 13.2"

with an uncertainty of 1.6 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. Amaral-Rogers (UoL) and S. R. Oates (UCL-MSSL) report on behalf of
the Swift-XRT team:

We have analysed 5.9 ks of XRT data for GRB 130627A (Oates  et al. GCN
Circ. 14933
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 ),  from 3.0 ks to 28.5 ks after the  BAT trigger. The data
are entirely in Photon Counting (PC) mode. The enhanced XRT position
for this burst was given by Osborne et al. (GCN. Circ 14945).

The light curve can be modelled with  a power-law decay with a decay
index of alpha=0.87 (+0.18, -0.16).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.4 (+/-0.3). The
best-fitting absorption column is  4.2 (+1.2, -1.1) x 10^21 cm^-2, in
excess of the Galactic value of 8.0 x 10^20 cm^-2 (Kalberla et al.
2005). The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum  is 3.5 x 10^-11 (8.4 x 10^-11) erg
cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:	     4.2 (+1.2, -1.1) x 10^21 cm^-2
Galactic foreground: 8.0 x 10^20 cm^-2
Excess significance: 5.3 sigma
Photon index:	     2.4 (+/-0.3)

If the light curve continues to decay with a power-law decay index of
0.87, the count rate at T+24 hours will be 6.4 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 2.3 x
10^-13 (5.4 x 10^-13) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00559132.

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

N. P. M. Kuin and S. R. Oates (UCL-MSSL) report on behalf of the
Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 130627A
2979 s after the BAT trigger (Oates et al., GCN Circ. 14933
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 , GCN Circ
14934
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 ).

No optical afterglow consistent with the (enhanced) XRT
position (Kennea et al. GCN Circ. 14935
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 ; Osborne et al. GCN Circ.
14945
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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          2979         3129          147         >20.5
white             2979        10701         1229         >22.1
v                 3136         4772          393         >19.7
b                 3956         9788         1125         >21.3
u                 3751         5386          393         >20.5
w1                3546         5182          393         >20.4
m2                3341         4976          393         >20.4
w2                4367        11202          684         >21.2

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.09 in the direction of the burst
(Schlegel et al. 1998).

G. Sato (ISAS), 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), A. Y. Lien (NASA/GSFC/ORAU), C. B. Markwardt (GSFC),
S. R. Oates (UCL-MSSL), D. M. Palmer (LANL), T. Sakamoto (AGU),
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 the recent telemetry downlink,
we report further analysis of BAT GRB 130627A (trigger #559132)
(Oates, et al., GCN Circ. 14933
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 ).  The BAT ground-calculated position is
RA, Dec = 184.415, -37.114 deg which is
  RA(J2000)  =  12h 17m 39.7s
  Dec(J2000) = -37d 06' 51.8"
with an uncertainty of 2.8 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 20%.

The mask-weighted light curve shows a single peak starting at ~T-4 sec,
peaking at ~T+2 sec, and ending at ~T+26.
T90 (15-350 keV) is 30.8 +- 12.3 sec (estimated error including systematics).

The time-averaged spectrum from T-5.2 to T+33.6 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.84 +- 0.32.  The fluence in the 15-150 keV band is 9.1 +- 1.9 x 10^-07 erg/cm2.
The 1-sec peak photon flux measured from T+1.88 sec in the 15-150 keV band
is 1.8 +- 0.5 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/559132/BA/