Gamma-ray Burst 141102A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

• none

• GCN Circular #17020
  J. R. Cummings on behalf of the Swift science team:
  A possibly short burst occurred at 12:51:40 UT (BAT trigger 617313). No source was found onboard. Ground analysis shows a significant source at RA, Dec 208.614, -47.100 which is:

  RA (J2000)     13h 54m 27.4s
  Dec (J2000)    -47d 06' 00"
  

  with an estimated uncertainty of 4 arcmin radius, 90% containment.
  There were multiple peaks, at about T-0.2, T+0.4, T+1.7, and T+2.3. The latter two were stronger than the first two and resembled them in shape, the third was the largest. T90 is estimated as 2.5 +- 0.4 sec.
  The spectrum from T-0.3 to T+2.7 seconds is best fit by a simple powerlaw function with a photon index of 1.3 +- 0.5. The fluence was 3.7 x 10 ^-7 ergs/cm^2.
  A Swift TOO is not possible because the source is too close to the Sun for the next 39 days.
• GCN Circular #17021
  Bin-Bin Zhang (UAH) reports on behalf of the Fermi GBM Team:
  "At 12:51:39.26 UT on the 2nd of November 2014, the Fermi Gamma-Ray Burst= Monitor =C2=A0triggered and located GRB 141102A (trigger 436625502 / 141102536), = which was also=C2=A0 detected by Swift (Cummings 2014, GCN 17020). The GBM on-ground location,= using=C2=A0 the Fermi GBM trigger data, is consistent with the Swift location. The tr= igger resulted in =C2=A0an Autonomous Repoint Request (ARR) that was accepted and the space= craft slewed =C2=A0to the GBM in-flight location. The angle from the Fermi LAT boresig= ht is about 57 degrees.
  The GBM light curve consists of two main peaks with a total duration (T90= ) of about =C2=A02.62 s (50=E2=80=93300 keV). The time-averaged spectrum from T0=E2=80= =930.064 s to T0+2.56 s is=C2=A0 well fit by a power law function with an exponential high-energy cutoff. = The power law=C2=A0 index is =E2=80=930.85 +/- 0.12 and the cutoff energy, parameterized as E= peak, is 770 +/- 243 keV.
  The event fluence (10=E2=80=931000 keV) in this time interval is (1.7 +/-= 0.1)E=E2=80=9306 erg/cm^2. The 1-sec peak photon flux measured starting from T0+1.1 s in the 10=E2=80=93= 1000 keV band is=C2=A0 5.0 +/- 0.2 ph/s/cm2.
  The spectral analysis results presented above are preliminary; final resu= lts will be published =C2=A0in the GBM GRB Catalog."
• GCN Circular #17022
  G.Vianello (Stanford U.), D. Kocevski (NASA/GSFC), V. Connaughton (UAH), M. Arimoto (Tokyo Tech), S. Guiriec (NASA/GSFC)
  At 12:51:39.26 on November 2, 2014, Fermi-LAT detected faint high-energy emission from the short GRB 141102A, which was also detected by Fermi-GBM (Zhang et al., GCN 17021) and Swift/BAT (Cummings et al., GCN 17020) and initiated an autonomous repoint of the spacecraft. The high-energy emission was detected during the ~300 s interval following the GBM trigger.
  The best LAT on-ground location is found to be
  (RA, Dec.) = 208.6, -47.7 deg
  with an error radius of 0.6 deg (90% containment, statistical error only), which is compatible with the position measured by Swift/BAT (Cummings et al., GCN 17020).
  Further follow up is encouraged.
  The Fermi-LAT point of contact for this burst is Makoto Arimoto (arimoto@hp.phys.titech.ac.jp).
  The Fermi-LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden.
• GCN Circular #17024
  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 long duration GRB 141102A (Swift-BAT detection: Cummings et al., GCN 17020; Fermi-GBM detection: Zhang, GCN Circ. 17021) triggered Konus-Wind at T0=46296.656 s UT (12:51:36.656).
  The KW triggered on the most intense episode with a duration of about 0.6 s. There is a possible precursor at ~T0-80 s.
  The emission in this episode is seen up to ~1 MeV.
  The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB141102_T46296/
  As observed by Konus-Wind, the episode had a fluence of 1.43(-0.42,+1.28)x10^-6 erg/cm2, and a 16-ms peak flux, measured from T0-0.022 s, of 5.95(-2.53,+7.28)x10^-6 erg/cm2/s (both in the 20 keV - 10 MeV energy range).
  The time-averaged spectrum of the episode (measured from T0 to T0+0.256 s) is best fit in the 20 keV - 1 MeV range by a power law with exponential cutoff model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep) with alpha = -0.58 (-0.61,+0.93) and Ep = 444 (-192,+1246) keV (chi2 = 21/28 dof). Fitting by a GRB (Band) model yields the same alpha and Ep, and an upper limit on the high energy photon index: beta < -1.3 (chi2 = 21/27 dof)
  All the quoted errors are at the 90% confidence level. All the quoted values are preliminary.
• GCN Circular #17025
  J. R. Cummings reports on behalf of the Swift science team:
  The emission at ~T-80 that was mentioned in Golenetskii et al. (GCN Circ # 17024) as apossible precursor to GRB 141102A was observed by BAT (trigger # 617315). It was not a precursor, but rather a soft burst from GX 354-0.