GRB 130701A

N. P. M. Kuin (UCL-MSSL), D. Malesani (DARK/NBI),
K. L. Page (U Leicester), D. M. Palmer (LANL), T. Sakamoto (AGU),
M. Stamatikos (OSU/NASA/GSFC) and T. N. Ukwatta (MSU) report on behalf
of the Swift Team:

At 04:17:43 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 130701A (trigger=559482).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 357.216, +36.099 which is 
   RA(J2000) = 23h 48m 52s
   Dec(J2000) = +36d 05' 58"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a double-peaked
structure with a duration of about 8 sec.  The peak count rate
was ~10304 counts/sec (15-350 keV), at ~1 sec after the trigger. 

The XRT began observing the field at 04:19:09.1 UT, 85.5 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 357.2287, 36.0997 which is equivalent to:
   RA(J2000)  = +23h 48m 54.89s
   Dec(J2000) = +36d 05' 58.9"
with an uncertainty of 5.3 arcseconds (radius, 90% containment). This
location is 37 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. 

UVOT took a finding chart exposure of 250 seconds with the U filter starting
150 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 19.2 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 18.0 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.09. 

Burst Advocate for this burst is N. P. M. Kuin (n.kuin 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.)

G. Leloudas (OKC, Stockholm and DARK/NBI), N. R. Tanvir (Univ. 
Leicester), D. Xu (DARK/NBI), D. Malesani (DARK/NBI), P. Jakobsson 
(Univ. Iceland), O. Smirnova (NOT and Univ. Latvia), M. G. Pedersen 
(Univ. Aarhus), report:

We observed the field of GRB 130701A (Kuin et al., GCN 14953
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 ) with the 
NOT equipped with the ALFOSC camera. Observations were carried out in 
the R band and started on 2013 Jul 1.198 UT (28 min after the GRB). We 
detect a new object not visible in the DSS and SDSS surveys, at coordinates:

RA(J2000) = 23:48:55.09
Dec(J2000) = +36:06:01.4

The object had a magnitude R = 17.55 at 04:49 UT, calibrated against 
SDSS stars converted to Johnson R. The source decayed by 0.25 mag by 
04:58 UT, hence confirming it is the afterglow of GRB 130701A.

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

Using 687 s of XRT Photon Counting mode data and 2 UVOT
images for GRB 130701A, 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 = 357.22942, +36.10058 which is equivalent
to:

RA (J2000): 23h 48m 55.06s
Dec (J2000): +36d 06' 02.1"

with an uncertainty of 2.0 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.

D. Xu (DARK/NBI), A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), D. Malesani (DARK/NBI), P. Vreeswijk (Weizmann), V. D'Elia (INAF-OAR, ASI-ASDC), J. P. U. Fynbo (DARK/NBI), B. Milvang-Jensen (DARK/NBI), H. Flores (GEPI/Obs. de Paris), O. Hartoog (Amsterdam), P. Goldoni (APC, CEA/Irfu), L. Kaper (Amsterdam), S. D. Vergani (CNRS/GEPI)

We observed the afterglow of GRB 130701A (Kuin et al. GCN 14953
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 , Leloudas et al. GCN 14954
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 ) with VLT/X-shooter, beginning at 2013-07-01 09:45 UT, about 5.5 hours after the burst. We obtained 2 spectra of 600s each, covering the wavelength range 3000-21000A.

From the acquisition image (Jul 1.404 UT, 5.40 hr after the GRB) we obtain a magnitude of R = 19.9 using the same calibration as in Leloudas et al. (GCN 14954
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 ).

Preliminary analysis of the spectrum reveals absorption lines of FeII
2344, 2374, 2382, MgII 2796, 2803, MgI 2852, CaII 3934, 3969 at a common redshift of z=1.155. We propose this to be the redshift of the GRB.

We thank the staff at Paranal, particularly Jonathan Smoker and Nestor Jimenez, for obtaining these observations.

[GCN OPS NOTE(01jul13) Per A.Breeveld's observation, the GRB name in the Subject-line was corrected.]

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

The Swift/UVOT began settled observations of the field of GRB 130701A
with the u filter 151 s after the BAT trigger (Kuin et al., GCN Circ. 
14953
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 ).
A source consistent with the enhanced XRT position (Beardmore et al., 
GCN Circ. 14955
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 ) and NOT position (Leloudas et al., GCN Circ. 14954
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 ) is 
detected in the initial UVOT exposures. There is a faint USNO-B1 source 
2.16" away (USNO-B1 1261-054544, with B2 mag of 21.10) which perhaps 
could be the host galaxy for the GRB.

Preliminary detections using the UVOT photometric system (Breeveld et 
al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are:

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

u_FC               151          400          246         15.52 � 0.1
v                 5950         6150          197         19.04 � 0.2
b                 5538         5737          197         19.66 � 0.2
w2                5744         5944          197         20.07 � 0.4

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).

S. Golenetskii, R.Aptekar, D. Frederiks, V. Pal'shin,
P. Oleynik, M. Ulanov, D. Svinkin, and T. Cline,
on behalf of the Konus-Wind team, report:

The long-duration, soft-spectrum GRB 130701A
(Swift-BAT trigger 559482: Kuin, et al., GCN 14953
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 )
triggered Konus-Wind at T0=15462.161 s UT (04:17:42.161)

The light curve shows a multi-peaked pulse from ~T0-0.5 s to ~T0+5 s.
The emission is seen up to 0.5 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB130701_T15462/

As observed by Konus-Wind, the burst
had a fluence of (5.8 � 0.2)x10-6 erg/cm2,
and a 64-ms peak flux, measured from T0+0.896 s,
of (4.3 � 0.4)x10-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-integrated spectrum (measured from T0 to T0+8.448 s)
is best fit in the 20 keV - 1.2 MeV range
by the cutoff power law with the following model parameters:
the photon index alpha = -1.1 � 0.1,
the peak energy Ep = 89 � 4 keV,
chi2 = 55.1/60 dof.

Assuming z=1.155 (Xu, et al., GCN 14956
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 ),
and a standard cosmology model with H_0 = 70 km/s/Mpc,
Omega_M = 0.27, and Omega_Lambda = 0.73,
we estimate the following rest-frame parameters of the burst:
the isotropic energy release E_iso ~ 2.1x10^52 erg,
the peak luminosity (L_iso)_max ~ 3.3x10^52 erg/s,
and the rest-frame peak energy Ep,i ~ 190 keV

All the quoted results are preliminary.

T. Sakamoto (AGU), 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), N. P. M. Kuin (UCL-MSSL),
A. Y. Lien (NASA/GSFC/ORAU), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), 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+349 sec from the recent
telemetry downlink, we report further analysis of BAT
GRB 130701A (trigger #559482) (Kuin, et al., GCN Circ. 14953
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 ).
The BAT ground-calculated position is RA, Dec = 357.224, 36.100 deg
which is
   RA(J2000)  =  23h 48m 53.7s
   Dec(J2000) = +36d 05' 58.4"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90%
containment). The partial coding was 28%.

BAT mask-weighted light curve shows overlapping two-peak structure
starting from T-1 sec with first peak around T+1 sec and
second peak around T+3 sec. The episode ends around T+5 sec.
T90 (15-350 keV) is 4.38 +- 0.25 sec (estimated error
including systematics).

The time-averaged spectrum from T-1.14 to T+5.35 sec is best
fit by a power law with an exponential cutoff.  This fit gives a
photon index 0.90 +- 0.21, and Epeak of 89.2 +- 12.4 keV
(chi squared 40.06 for 56 d.o.f.).  For this model the total fluence
in the 15-150 keV band is 4.4 +- 0.1 x 10^-06 erg/cm2 and the 1-sec
peak flux measured from T+0.06 sec in the 15-150 keV band is
17.1 +- 0.7 ph/cm2/sec.  A fit to a simple power law gives a
photon index of 1.58 +- 0.05 (chi squared 76.39 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/559482/BA/

S. B. Cenko (NASA/GSFC) and D. A. Perley (Caltech) report on behalf of a
larger collaboration:

We have observed the location of the Swift GRB130701A (Kuin et al., GCN
14953
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 ) with the robotic Palomar 60 inch telescope. Observations were
obtained in non-photometric conditions in the r', i', and z' filters
beginning at 06:52 UT on 2013 July 1 (2.58 hr after the Swift trigger).
Using nearby point sources from SDSS for photometric calibration, we
measure afterglow magnitudes of r' = 19.57 +/- 0.12 and i' = 19.36 +/-
0.10 at approximately this time.  Compared with the earlier detection from
the NOT (Leloudas et al., GCN 14954
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 ), this implies a power-law decay index
of alpha ~ 1.0.

M.C. Stroh (PSU), D.N. Burrows (PSU), K.L. Page (U. Leicester), C.
Pagani (U. Leicester), A.P. Beardmore (U. Leicester), A. Maselli 
(INAF-IASFPA), V. Mangano (INAF-IASFPA), A. Melandri (INAF-OAB), J.A.
Kennea (PSU) and N.P.M. Kuin report on behalf of the Swift-XRT team:

We have analysed 7.6 ks of XRT data for GRB 130701A (Kuin  et al. GCN
Circ. 14953
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 ),  from 91 s to 36.5 ks after the  BAT trigger. The data
comprise 214 s in Windowed Timing (WT) mode with the remainder in
Photon Counting (PC) mode. The enhanced XRT position for this burst was
given by Beardmore et al. (GCN. Circ 14955).

The light curve can be modelled with an initial power-law decay with an
index of alpha=1.02 (+0.03, -0.06), followed by a break at T+2249 s to
an alpha of 1.38 (+0.10, -0.08).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index	of 2.19 (+/-0.10). The
best-fitting absorption column is  1.29 (+0.22, -0.20) x 10^21 cm^-2,
in excess of the Galactic value of 6.9 x 10^20 cm^-2 (Kalberla et al.
2005). The PC mode spectrum has a photon index of 1.97 (+0.16, -0.15)
and a best-fitting absorption column of 1.3 (+/-0.4) x 10^21 cm^-2. The
counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum  is 3.8 x 10^-11 (5.0 x 10^-11) erg cm^-2
count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:	     1.3 (+/-0.4) x 10^21 cm^-2
Galactic foreground: 6.9 x 10^20 cm^-2
Excess significance: 2.8 sigma
Photon index:	     1.97 (+0.16, -0.15)

If the light curve continues to decay with a power-law decay index of
1.38, the count rate at T+24 hours will be 7.5 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 2.8 x
10^-13 (3.8 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/00559482.

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

T. Yoshii, K. Ito, Y. Saito, Y. Yano, R. Usui, Y. Tachibana, 
S. Kurita, Y. Yatsu, and N. Kawai (Tokyo Tech)
report on behalf of the MITSuME collaboration:

We observed the field of GRB 130701A (N. P. M. Kuin et al., GCNC 14953) with the 
optical three color (g, Rc, and Ic) CCD cameras attached to the MITSuME 50 cm
telescope of Akeno Observatory, Yamanashi, Japan.

The observation started on 2013-07-01 14:33:09 UT ( ~10.3 h after
the burst). And we could not find any new point source within the XRT
error circle (N. P. M. Kuin et al., GCNC 14953) in all the three bands.

The results of photometry (3 sigma upper limits) are listed below.
We used GSC2.3 catalog for flux calibration.


band     T0+[hour]     MID-UT        T-EXP[sec]     magnitude
--------------------------------------------------------------------------------------------
g'             ~13.0           17:19:49         1680               >19.2
Rc           ~13.1           17:24:36         2880               >18.9
Ic             ~13.0           17:17:28         1320              >18.0
--------------------------------------------------------------------------------------------
T0+ : Elapsed time after the burst [hour]
T-EXP: Total Exposure time [sec]