GRB 141130A

A. Vargas (PSU), S. D. Barthelmy (GSFC),
H. A. Krimm (CRESST/GSFC/USRA), D. Malesani (DARK/NBI),
F. E. Marshall (NASA/GSFC), D. M. Palmer (LANL) and
B. Sbarufatti (INAF-OAB/PSU) report on behalf of the Swift Team:

At 23:10:56 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 141130A (trigger=620090).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 222.814, +47.300 which is 
   RA(J2000)  =  14h 51m 15s
   Dec(J2000) = +47d 17' 60"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows a single peak
structure with a duration of about 35 sec.  The peak count rate
was ~1200 counts/sec (15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 23:12:20.3 UT, 84.3 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
fading, uncatalogued X-ray source with an enhanced position: RA, Dec
222.8205, 47.3202 which is equivalent to:
   RA(J2000)  = 14h 51m 16.92s
   Dec(J2000) = +47d 19' 12.7"
with an uncertainty of 2.8 arcseconds (radius, 90% containment). This
location is 74 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 1.82
x 10^20 cm^-2 (Willingale et al. 2013). 

The initial flux in the 2.5 s image was 8.27e-10 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of nominal 150.000 seconds with the White
filter starting 93 seconds after the BAT trigger. There is a candidate
afterglow in the list of sources generated on-board at
  RA(J2000)  =	14:51:17.28 = 222.82199
  DEC(J2000) = +47:19:07.5  =  47.31876
with a 90%-confidence error radius of about 1.10 arc sec. This position is 4.1
arc sec. from the center of the XRT error circle. The estimated magnitude is
18.74. No correction has been made for the expected extinction corresponding to
E(B-V) of 0.02. 

Burst Advocate for this burst is A. Vargas (avargas AT swift.psu.edu). 
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. Mazaeva (IKI), E. Klunko (ISTP), I. Korobtsev (ISTP), M. Eselevich 
(ISTP), A. Volnova (IKI), A. Pozanenko (IKI) report on behalf of larger 
GRB follow-up collaboration:

We observed the field of GRB 141130A (Vargas et al., GCN  17120
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 ) with 
AZT-33IK telescope of Sayan observatory (Mondy) Nov., 30  starting on 
(UT) 23:15:04, i.e 248 s after burst trigger. In first images of 10 s 
exposure we clearly detect fading object in coordinates of the OT 
candidate reported in  (Vargas et al., GCN  17120
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 ). The object is absent 
in DSS2 and we thus confirm optical afterglow of GRB 141130A.  The 
afterglow has faded from R = 18.5 +/- 0.14 at 258 s after burst trigger 
to R = 19.2 +/- 0.2 at 800 s  after burst trigger.

The photometry is stil preiminary and based on nearby USNO-B1.0 stars.

D. Xu (DARK/NBI), T.-Z. Yang, G.-J. Feng, A. Esamdin, L. Ma (XAO) report:

We observed the field of GRB 141130A (Vargas et al., GCN  17120
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 ) with
the 1m optical telescope located at Nanshan, Xinjiang, China.
Observations started at 23:36:49 UT on 2014-10-30 (i.e., 1553 s after
the burst) and a series of 120s, 180s, and 360s R-band images were
obtained under some clouds. We detect the optical afterglow at the
UVOT position with R~19.1 mag at the median time of 1982 s post-burst,
calibrated with four nearby SDSS stars (SDSS J145120.41+471920.1, SDSS
J145118.89+471810.3, SDSS J145125.69+471701.0, and SDSS
J145114.11+471610.1).

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

Using 621 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 141130A, 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 = 222.82159, +47.31852 which is equivalent
to:

RA (J2000): 14h 51m 17.18s
Dec (J2000): +47d 19' 06.7"

with an uncertainty of 1.9 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.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), B.P. Gompertz
(U. Leicester), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), M. de
Pasquale (INAF-IASFPA), J.A. Kennea (PSU), V. Mangano (PSU), M.C. Stroh
(PSU) and A. Vargas report on behalf of the Swift-XRT team:

We have analysed 11 ks of XRT data for GRB 141130A (Vargas  et al. GCN
Circ. 17120
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 ),  from 75 s to 28.5 ks after the  BAT trigger. The data
comprise 327 s in Windowed Timing (WT) mode (the first 6 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 Goad et al.
(GCN Circ. 17123
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 ).

The late-time light curve (from T0+4.9 ks) can be modelled with  a
power-law decay with a decay index of alpha=1.14 (+0.26, -0.25).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index	of 2.31 (+0.07, -0.06). The
best-fitting absorption column is  1.50 (+0.17, -0.16) x 10^21 cm^-2,
in excess of the Galactic value of 1.8 x 10^20 cm^-2 (Willingale et al.
2013). The PC mode spectrum has a photon index of 2.13 (+0.25, -0.21)
and a best-fitting absorption column of 3.8 (+4.7, -2.0) x 10^20 cm^-2.
The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum  is 3.1 x 10^-11 (3.4 x 10^-11) erg cm^-2
count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:	     3.8 (+4.7, -2.0) x 10^20 cm^-2
Galactic foreground: 1.8 x 10^20 cm^-2
Excess significance: <1.6 sigma
Photon index:	     2.13 (+0.25, -0.21)

If the light curve continues to decay with a power-law decay index of
1.14, the count rate at T+24 hours will be 1.8 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 5.5 x
10^-14 (6.2 x 10^-14) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00620090.

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

S. R. Oates (IAA-CSIC/UCL-MSSL) and A. Vargas (PSU) report
on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of
GRB 141130A 95 s after the BAT trigger (Vargas et al., GCN
Circ. 17120
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 ).  A source consistent with the XRT position
(Goad et al. GCN Circ. 17123
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 )  is detected in the initial UVOT
exposures.

The preliminary UVOT position is:
    RA  (J2000) =  14:51:17.23 = 222.82181 (deg.)
    Dec (J2000) = +47:19:07.3  =  47.31870 (deg.)
with an estimated uncertainty of 0.45 arc sec. (radius, 90% confidence).

Preliminary detections and 3-sigma upper limits 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

white               95          244          147         18.71 +/- 0.06
v                  636          655           19        >17.8
b                  562          753           39        >20.1
u                  306          556          246         18.85 +/- 0.13
w1                 684          704           19        >18.7
w2                 611          798           34        >19.0

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.02 in the direction of the burst
(Schlegel et al. 1998).

[GCN OPS NOTE(01dec14):  Per author's request, the "A" was added
to the GRB name.]

A. Y. Lien (GSFC/UMBC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),
C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU),
M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (LANL), A. Vargas (PSU)
(i.e. the Swift-BAT team):
 
Using the data set from T-240 to T+962 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 141130A (trigger #620090)
(Vargas, et al., GCN Circ. 17120
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 ).  The BAT ground-calculated position is
RA, Dec = 222.804, 47.323 deg which is 
   RA(J2000)  =  14h 51m 13.0s 
   Dec(J2000) = +47d 19' 24.3" 
with an uncertainty of 1.4 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 73%.
 
The mask-weighted light curve shows the burst starting at ~T-43 sec, going
flat until ~T-10 sec, then peaking at ~T-2 sec, and then returing
to baseline ~T+60 sec.  T90 (15-350 keV) is 62.9 +- 11.4 sec
(estimated error including systematics).
 
The time-averaged spectrum from T-42.75 to T+40.02 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.56 +- 0.08.  The fluence in the 15-150 keV band is 2.8 +- 0.1 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T-4.69 sec in the 15-150 keV band
is 1.2 +- 0.2 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/620090/BA/

E. Mazaeva (IKI), E. Klunko (ISTP), I. Korobtsev (ISTP), M. Eselevich 
(ISTP), A. Volnova (IKI), A. Pozanenko (IKI) report on behalf of larger 
GRB follow-up collaboration:

We report optical light curve of the GRB 141130A (Vargas et al., GCN 
17120
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 ) based on our observations with AZT-33IK telescope of Sayan 
observatory (Mondy) on  Nov., 30 (Mazaeva et al., GCN 17121
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 ).

The light curve can be found in 
http://grb.rssi.ru/GRB141130A/GRB141130A_AZT33IK_lc.png

The photometry is based on nearby USNO-B1.0 stars.

E. Mazaeva (IKI), A. Volnova (IKI), E. Klunko (ISTP), I. Korobtsev 
(ISTP), M. Eselevich (ISTP), A. Pozanenko (IKI) report on behalf of 
larger GRB follow-up collaboration:

We observed the field of GRB 141130A (Vargas et al., GCN  17120
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 ) with 
AZT-33IK telescope of Sayan observatory (Mondy) Dec., 01  starting on 
(UT) 21:21:55. We obtained several  images in R-filter. In a combined 
image we do not detect optical  afterglow (Vargas et al., GCN  17120
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 ; 
Mazaeva et al., GCN 17121
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 ; Xu et al., GCN 17122
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 ).


Upper limit  is based on nearby USNO B1.0 (R2) stars:

date       UT start   t-T0     Filter   Exp.    OT    UL(3 sigma)
                       (mid, days)       (s)

2014-12-01 21:21:55   0.95417  R        43*120  n/d   22.1


The finding chart can be found in
http://grb.rssi.ru/GRB141130A/GRB141130_20141201_AZT33IK_fc.png

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

The long GRB 141130A (Swift-BAT trigger #620090: Vargas et al., GCN 17120
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 ;
Lien et al., GCN 17127
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 ) was detected by Konus-Wind in the waiting mode.

The burst light curve shows a double-peaked structure
with a total duration of ~85 s (from ~T0(BAT)-44 s to ~T0(BAT)+41 s).

As observed by Konus-Wind, the burst had a fluence of
8.79(-2.39,+2.62)x10^-6 erg/cm2 and a 2.944 s peak flux,
measured from ~T0(BAT)-2.725 s, of 2.40(-0.82,+0.87)x10^-7 erg/cm2/s
(both estimated in the 20 keV - 10  MeV energy range).

Modeling the KW 3-channel time-integrated spectrum
(from T0(BAT)-43.941 s to T0(BAT)+41.435 s) by a power law
with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
yields alpha =-1.49 �� 0.18,
and Ep =307(-108,+467) keV.

The K-W light curve of this burst is available at
http://www.ioffe.ru/LEA/GRBs/GRB141130A/

All the quoted errors are at 1 sigma confidence level.
All the quoted values are preliminary.