GRB 140930B

E. Gorbovskoy, V. Lipunov, M.Pruzhinskaya,  V.Kornilov, D.Kuvshinov, N.Tyurina, 
P.Balanutsa, A.Kuznetsov, V.V.Chazov, D.Denisenko
Lomonosov Moscow State University,
Sternberg Astronomical Institute, Moscow State University

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

V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov, A. Gabovich
Blagoveschensk Educational State University, Blagoveschensk

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

V.Krushinski, I.Zalozhnih,  A. Popov
Ural Federal University, Kourovka

Hugo Levato and Carlos Saffe
Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)

Claudio Mallamaci, Carlos Lopez and Federico Podest
Observatorio Astronomico Felix Aguilar (OAFA)


Two MASTER II twin  robotic telescope (MASTER-Net: 
http://observ.pereplet.ru)  located in  Blagoveschensk  and Kislovodsk was 
pointed to the  GRB140930B (Pasquale et. al GCN 16857
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 ) 21 and 36 sec after
notice time and  39 and 54 sec after trigger time respectively.

So we have 4 first images in four different polarization started after 21 
sec (Blagoveschensk) and 36 sec (Kislovodsk) with 10 sec exposure.
We found 3-sigma OT    on one  tube image in Blagoveschensk at the
WHT  position (Tanvir et. al, GCN16861
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 , Fong et. al. GCN16863
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 ) with m = 
16+-0.5 mag. The OT seen at one first image only.
The image with OT is available at 
http://master.sai.msu.ru/static/GRB/GRB140930B_MASTER_OT.png

We do not see OT (Tanvir et. al GCN16857
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 , Fong et. al. GCN16857
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 ) on three
tube images on single and coadd images.
The analysis strongly is complicated by presence of very bright star (USNO 
B1 1142-0005722 ~14m) close to OT position. 
The upper limits received by MASTER are given in the table below:


t_start      | t-t_mid    | exptime | filt | lim  | site | coadd
--------------------------+---------+------+------+------+-------
19:42:21.909 | 44 sec     |      10 | P/   | 16.4 | A    |     1
19:42:21.909 | 44 sec     |      10 | P\   | 15.7 | A    |     1*
19:42:36.837 | 59 sec     |      10 | P|   | 15.6 | K    |     1
19:42:36.837 | 59 sec     |      10 | P-   | 16.0 | K    |     1
19:42:21.909 | 70 sec     |      40 | P/   | 17.3 | A    |     3
19:42:36.837 | 98 sec     |      50 | P-   | 16.9 | K    |     3
19:42:21.909 | 130 sec    |     130 | P/   | 18.5 | A    |     6
19:44:26.834 | 243 sec    |     120 | P-   | 18.0 | K    |     3
19:42:36.837 | 188 sec    |     170 | P-   | 18.6 | K    |     6
19:42:36.837 | 692 sec    |    1060 | P-   | 19.9 | K    |    13
19:42:21.909 | 698 sec    |    1160 | P/   | 19.7 | A    |    14
20:29:14.938 | 6120 sec   |    5400 | C    |~21.5 | K    |    30

* possible OT

C is  our white (clear) band which is well described by a parity 0.8R+0.2B (USNO B1).

P/ and P\ is a polarization filter which are oriented at an angle 45 and 
135 degrees to RA axis respectivel. P- and P| is a polarization filter 
which are oriented at an angle 0 and 90 degrees to RA axis respectivel.

This message may be cited.

S. B. Cenko, A. Cucchiara (NASA/GSFC), N. R. Tanvir (U. Leicester), A. J. Levan (U. Warwick), and D. A. Perley (Caltech) report on behalf of a larger collaboration:

We obtained a spectrum of the optical afterglow (Tanvir et al., GCN 16861
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 ; Fong et al., GCN 16863
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 ) of the short GRB 130930B (De Pasquale et al., GCN 16857
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 ) with the Gemini Multi-Object Spectrograph mounted on the 8 m Gemini South telescope.  Observations began at 4:01 UT on 2014 October 1 (8.3 hr after the Swift trigger) and cover the wavelength range from 3700-8300 A.

We detect a weak continuum trace at the location of the afterglow over most of the observed wavelength range (lambda >~ 4000 A), but no obvious emission or absorption features.

J. Graham (MPE Garching), A. Nicuesa Guelbenzu (TLS Tautenburg), J. Bolmer 
and J. Greiner (both at MPE Garching) report on behalf of the GROND team:

We observed the field of GRB 140930B (Swift trigger 614094; De Pasquale et 
al., GCN #16857
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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 MPG telescope at La Silla 
Observatory (Chile).

Observations started at 02:25 UT on 1 October 2014, around 7 hours after 
the GRB trigger. They were performed at an average seeing of 1.4" and at 
an average airmass of 1.9.

We detect the afterglow candidate reported by Tanvir et al. (GCN #16861
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 ) 
and confirmed by Fong et al. (GCN #16863
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 ). At a midtime of 03:00 UT we 
measure a preliminary AB magnitude of

r' = 23.2 +/- 0.2 mag.

The analysis of the other GROND photometric bands is still on-going. We 
note that the photometry is slightly affected by a bright star next to the 
afterglow.

The given magnitude is calibrated against SDSS field stars and not 
corrected for the expected Galactic foreground extinction corresponding to 
a reddening of E_(B-V)=0.04 mag in the direction of the burst (Schlegel et 
al. 1998).

W. H. Baumgartner (GSFC/UMBC), S. D. Barthelmy (GSFC),
J. R. Cummings (GSFC/UMBC), M. De Pasquale (INAF-IASFPA), N. Gehrels (GSFC),
H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU), J. Tueller (GSFC),
T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):

Using the data set from T-61 to T+174 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 140930B (trigger #614094)
(De Pasquale, et al., GCN Circ. 16857
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 ).  The BAT ground-calculated position is
RA, Dec = 6.360, 24.298 deg which is
    RA(J2000)  =  00h 25m 26.4s
    Dec(J2000) = +24d 17' 53.3"
with an uncertainty of 1.6 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 24%.

The mask-weighted light curve shows a single FRED-like peak with structure,
beginning at ~T-0.1 sec, peaking at T+0 sec and decaying to background by
T+1.0 sec.   There is no clear sign of extended emission.
T90 (15-350 keV) is 0.84 +- 0.12 sec (estimated error including systematics).

The time-averaged spectrum from T-0.10 to T+0.86 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
0.64 +- 0.19.  The fluence in the 15-150 keV band is 4.2 +- 0.4 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T-0.12 sec in the 15-150 keV band
is 4.0 +- 0.4 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.   The position of GRB 140930B in the BAT hardness-duration diagram places
it clearly in the short hard burst part of the diagram.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/614094/BA/

A. A. Breeveld (UCL-MSSL) and M. De Pasquale (INAF-IASFPA) report on 
behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 140930B 
201s after the BAT trigger (De Pasquale et al., GCN Circ. 16857
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 ).
No optical afterglow consistent with the XRT position (Goad et al., GCN 
Circ. 16865
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 ) or the optical position (Tanvir et al., GCN Circ. 16861
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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           201          351          147         >20.2
white              201         2579          528         >20.9
v                  507         2629          253         >18.8
b                  433         2787          311         >19.9
u                  407         2702          253         >19.4
w1                 383         2678          253         >19.4
m2                 358         2653          214         >19.3
w2                 483         2605          253         >19.7

The magnitudes in the table are not corrected for the Galactic 
extinction due to the reddening of E(B-V) = 0.03 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, A. Tsvetkova, A. Lysenko, and T. Cline
on behalf of the Konus-Wind team, report:

A short-duration, hard-spectrum GRB 140930B (Swift-BAT detection: 
Pasquale et al., GCN 16857
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 ) triggered Konus-Wind at T0=70907.149 s UT 
(19:41:47.149).

The burst light curve shows a single pulse with a duration of ~1.0 s.
The emission is seen up to ~10 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB140930_T70907/

As observed by Konus-Wind, the burst
had a fluence of 8.1(-2.5,+5.1)x10^-6 erg/cm2,
and a 16-ms peak flux, measured from T0-0.010 s,
of 3.4(-1.1,+2.3)x10^-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-averaged spectrum of the burst
(measured from T0 to T0+8.448 s)
is best fit in the 20 keV - 15 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with  alpha = -0.6 (-0.5,+0.6)
and Ep = 1302 (-459,+2009) keV (chi2 = 99/92 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -1.6
(chi2 = 98/91 dof)

All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.

D. A. Perley and J. Jencson (Caltech) report:

We imaged the location of short-duration GRB 140930B (De Pasquale et 
al., GCN 16857
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 ) using the Multi-Object Spectrometer for Infrared 
Exploration (MOSFIRE) on the Keck I 10 meter telescope between 08:44 and 
09:04 on 2014-10-01 (UT).   We acquired 9 x 35-second exposures in 
Ks-band and 9 x 44-second exposures in J-band.   A faint point-like 
source is detected at RA=00:25:23.433, dec=+24:17:39.41 (J2000), a 
location consistent with the afterglow locations previously reported by 
Evans et al. (GCN 16865
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 ) and Tanvir et al. (GCN 16861
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 ).  Photometry 
relative to 2MASS gives approximate magnitudes (Vega) of:

  J = 22.2 +/- 0.2    (tmid = 13.31 hr)
  Ks = 20.8 +/- 0.3   (tmid = 13.12 hr)

We thank M. Kasliwal and T. Prince for the observing time.

V. Mangano (PSU), M.C. Stroh (PSU), P.A. Evans (U. Leicester), B.P.
Gompertz (U. Leicester), J.P. Osborne (U. Leicester), V. D'Elia (ASDC),
M. de Pasquale (INAF-IASFPA), A. Maselli  (INAF-IASFPA), D.N. Burrows
(PSU) and M. De Pasquale report on behalf of the Swift-XRT team:

We have analysed 7.5 ks of XRT data for GRB 140930B (De Pasquale  et
al. GCN Circ. 16857
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 ),  from 182 s to 14.3 ks after the	BAT trigger.
The data comprise 8 s in Windowed Timing (WT) mode (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. 16859
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 ).

The light curve can be modelled with a series of power-law decays. The
initial decay index is alpha=2.13 (+0.21, -0.19). At T+952 s  the decay
flattens to an alpha of 0.95 (+0.23, -0.47) before breaking again at
T+6412 s to a final decay with index alpha=3.3 (+2.3, -1.3).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.71 (+0.16, -0.15). The
best-fitting absorption column is  6.0 (+4.3, -2.6) x 10^20 cm^-2,
consistent with the Galactic value of 3.5 x 10^20 cm^-2 (Willingale et
al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux
conversion factor deduced from this spectrum  is 3.8 x 10^-11 (4.2 x
10^-11) erg cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:	     6.0 (+4.3, -2.6) x 10^20 cm^-2
Galactic foreground: 3.5 x 10^20 cm^-2
Excess significance: <1.6 sigma
Photon index:	     1.71 (+0.16, -0.15)

If the light curve continues to decay with a power-law decay index of
3.3, the count rate at T+24 hours will be 5.8 x 10^-6 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 2.2 x
10^-16 (2.4 x 10^-16) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00614094.

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

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

Using 1478 s of XRT Photon Counting mode data and 3 UVOT
images for GRB 140930B, 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 = 6.34767, +24.29398 which is equivalent
to:

RA (J2000): 00h 25m 23.44s
Dec (J2000): +24d 17' 38.3"

with an uncertainty of 2.3 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.

W. Fong (U. Arizona), M. Calkins (SAO), and E. Berger (Harvard) report:

"We observed the location of the short-duration GRB 140930B (De Pasquale et
al., GCN 16857
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 ) with MMTCam mounted on the 6.5-m MMT starting on 2014 Oct
1.144 UT (7.76 hr post-burst). We obtained 4x300-sec of r-band observations
in 1" seeing. We detect a source at the position of the candidate optical
afterglow (Tanvir et al., GCN 16861
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 ) with a magnitude of r~24.0 +/- 0.2
(calibrated to SDSS), indicating that the source faded by ~2.2 mag between
3.0 hr and 7.8 hr post-burst. The fading confirms that this source is the
optical afterglow of GRB 140930B. Assuming a single power-law decline
between these two epochs, the decay index is alpha~-2.1.

We thank Nelson Caldwell for the rapid scheduling of these observations."

K. Polyakov (ISON), A. Pozanenko (IKI), A. Volnova (IKI),  I. Molotov 
(KIAM), report on  behalf of larger collaboration:

We observed the field of  GRB 140930B (De Pasquale et al., GCN 16857
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 ) 
with Santel-400AN   telescope of ISON-Kislovodsk observatory starting on 
Sep. 30 (UT) 19:52:24, i.e. ~10.5 minutes after burst trigger. We took 
30 unfiltered images of 120 s exposure. In the enhanced XRT position 
(Evans et al. GCN 16859
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 ) we do not detect the optical candidate (Tanvir 
et al., GCN 16861
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 ). A preliminary upper limit of the first image is 
19.5m (at mid time (UT) 19:53:24) and is based on nearby USNO-B1.0 
stars, R2 magnitudes.

N. R. Tanvir (U. Leicester), A. J. Levan (U. Warwick) and
M. Fraser (IoA, U. Cambridge) report:

We observed the position of GRB 140930B (De Pasquale et al.
GCN 16857
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 ) with ACAM on the WHT.  Observations began at
22:40 UT, approximately 3.0 hr post burst.

We detect a faint point source consistent with the
revised X-ray position (Evans et al. GCN 16859
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 ) with
a magnitude r~21.8 and position 00:25:23.45 +24:17:39.0
(provisional calibration).  We note that no source is visible at 
this location in the SDSS observations of the field and therefore 
suggest it is likely to be the afterglow of this burst.

J. Gorosabel (IAA-CSIC/UPV-EHU), S. Hellmich (DLR), S. Mottola (DLR), on
behalf of a larger collaboration report:

We observed the GRB 140930B (De Pasquale GCN 16857
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 ) field with the 1.23m
CAHA telescope. The observations were carried out in the R-band on Sep
30.82728-30.86076 UT (9.6-57.8 minutes post GRB). A very preliminary
analysis does not reveal any optical source consistent with the enhanced
XRT position (Evans et al. GCN 16859
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 ) brighter than R(Vega)~21, calibrated
against the USNO B1.0 catalog. A further analysis is ongoing.

P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team:

Using  promptly downlinked XRT event data for GRB 140930B, we find an
enhanced XRT position of the afterglow: RA, Dec: 6.3478, 24.2948 which
is equivalent to:
   RA (J2000)  = 00 25 23.46
   Dec (J2000) = +24 17 41.3
with an uncertainty of 2.0 arcseconds (radius, 90% confidence).
Analysis of the promptly available data is online at
http://www.swift.ac.uk/sper/614094.

Position enhancement is is described by Goad et al. (2007, A&A, 476,
1401) and Evans et al. (2009, MNRAS, 397, 1177).

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

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

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

V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov, A. Gabovich
Blagoveschensk Educational State University, Blagoveschensk

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

V.Krushinski, I.Zalozhnih,  A. Popov
Ural Federal University, Kourovka

Hugo Levato and Carlos Saffe
Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)

Claudio Mallamaci, Carlos Lopez and Federico Podest
Observatorio Astronomico Felix Aguilar (OAFA)



MASTER II  robotic telescope (MASTER-Net: http://observ.pereplet.ru) 
located in Blagoveschensk was pointed to the  GRB140930B 21 sec after 
notice time and 39 sec after trigger time at 2014-09-30 19:42:21 UT in two 
polarizations. On our first (10s exposure)  set we haven`t found optical 
transient  within SWIFT error-box (ra=00 25 25 dec=+24 16 28 r=0.050000).
The 5-sigma upper limit has been about 16.0 mag


MASTER II  robotic telescope (MASTER-Net: http://observ.pereplet.ru) 
located in Kislovodsk was pointed to the  GRB140930B 36 sec after notice 
time and 54 sec after trigger time at 2014-09-30 19:42:36 UT  in two 
polarizations. On our first (10s exposure)  set we haven`t found optical 
transient  within SWIFT error-box (ra=00 25 25 dec=+24 16 27 r=0.050000).
The 5-sigma upper limit has been about 15.5 mag

The observations on both observatories is continued.

M. De Pasquale (INAF-IASFPA), S. D. Barthelmy (GSFC),
N. Gehrels (NASA/GSFC), J. A. Kennea (PSU),
H. A. Krimm (CRESST/GSFC/USRA), V. Mangano (PSU),
C. B. Markwardt (NASA/GSFC), A. Maselli (INAF-IASFPA),
B. Sbarufatti (INAF-OAB/PSU), M. H. Siegel (PSU) and
C. A. Swenson (PSU) report on behalf of the Swift Team:

At 19:41:42 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 140930B (trigger=614094).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 6.355, +24.275, which is 
   RA(J2000)  =  00h 25m 25s
   Dec(J2000) = +24d 16' 30"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows a single spike
with a duration of about 2 sec.  The peak count rate
was ~11,000 counts/sec (15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 19:44:58.9 UT, 196.9 seconds after
the BAT trigger. Using promptly downlinked data we find a fading,
uncatalogued X-ray source located at RA, Dec 6.34833, 24.29681 which is
equivalent to:
   RA(J2000)  = 00h 25m 23.60s
   Dec(J2000) = +24d 17' 48.5"
with an uncertainty of 3.7 arcseconds (radius, 90% containment). This
location is 81 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 (3.45 x
10^20 cm^-2, Willingale et al. 2013), with an excess column of 4.8
(+3.58/-3.02) x 10^21 cm^-2 (90% confidence). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 201 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
0.03. 

Burst Advocate for this burst is M. De Pasquale (mdp AT ifc.inaf.it). 
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.)