//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 19326 SUBJECT: GRB 160419A: Swift detection of a burst DATE: 16/04/19 15:32:18 GMT FROM: David Palmer at LANL C. B. Markwardt (NASA/GSFC), J. A. Kennea (PSU), H. A. Krimm (CRESST/GSFC/USRA), A. Melandri (INAF-OAB), K. L. Page (U Leicester), D. M. Palmer (LANL), M. H. Siegel (PSU) and T. N. Ukwatta (LANL) report on behalf of the Swift Team: At 15:16:37 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 160419A (trigger=683383). Swift did not slew to the burst due to an observing constraint. The BAT on-board calculated location is RA, Dec 16.424, -27.343 which is RA(J2000) = 01h 05m 42s Dec(J2000) = -27d 20' 32" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single symmetric peak structure with a duration of about 20 sec. The peak count rate was ~5000 counts/sec (15-350 keV), at ~0 sec after the trigger. Due to a Sun observing constraint, Swift cannot slew to the BAT position until 01:44 UT on 2016 April 30. There will thus be no XRT or UVOT data for this trigger before this time. Burst Advocate for this burst is C. B. Markwardt (Craig.Markwardt AT nasa.gov). 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.) //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 19327 SUBJECT: GRB 160419A: Fermi GBM detection DATE: 16/04/19 21:27:21 GMT FROM: Bagrat Mailyan at UAH B. Mailyan (UAH), C. Meegan (UAH) and P. Veres (UAH) report on behalf of the Fermi GBM Team: "At 15:16:35.39 UT on 19 April 2016, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 160419A (trigger 482771799 / 160419.637), which was also detected by the Swift/BAT (C. B. Markwardt et al. 2016, GCN 19326). The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight at the GBM trigger time using the Swift BAT position is about 127 degrees. The GBM light curve consists of a weak burst with a duration (T90) of about 24 s (50-300 keV). The time-averaged spectrum from T0-1.3 s to T0+2.7 s is best fit by a power law function with an exponential high-energy cutoff function, with Epeak = 438 +/- 118 keV and alpha = -0.49 +/- 0.28. The event fluence (10-1000 keV) in this time interval is (1.675 +/- 0.221)E-06 erg/cm^2. The 1s peak photon flux measured starting from T0-1.15 s in the 10-1000 keV band is 1.92 +/- 0.25 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog." [GCN OPS NOTE(20apr16): In the Subject line, "150419A" was changed to "160419A"] //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 19328 SUBJECT: GRB 160419A, Swift-BAT refined analysis DATE: 16/04/21 12:58:28 GMT FROM: Amy Lien at GSFC J. R. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC), 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), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team): Using the data set from T-240 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 160419A (trigger #683383) (Markwardt et al., GCN Circ. 19326). The BAT ground-calculated position is RA, Dec = 16.418, -27.341 deg which is RA(J2000) = 01h 05m 40.3s Dec(J2000) = -27d 20' 28.7" with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 16%. The mask-weighted light curve shows a triangle-shaped, single-peaked structure that starts at ~ T-4 s, peaks at ~T0, and ends at ~T0+8 s. T90 (15-350 keV) is 8.8 +- 1.1 sec (estimated error including systematics). The time-averaged spectrum from T-4.5 to T+8.5 sec is best fit by a power law with an exponential cutoff. This fit gives a photon index 0.76 +- 0.33, and Epeak of 107.1 +- 35.2 keV (chi squared 40.46 for 56 d.o.f.). For this model the total fluence in the 15-150 keV band is 3.5 +- 0.2 x 10^-6 erg/cm2 and the 1-sec peak flux measured from T+0.00 sec in the 15-150 keV band is 8.9 +- 0.7 ph/cm2/sec. A fit to a simple power law gives a photon index of 1.40 +- 0.07 (chi squared 53.01 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/683383/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 19332 SUBJECT: GRB 160419A: CALET Gamma-Ray Burst Monitor detection DATE: 16/04/22 22:58:00 GMT FROM: Takanori Sakamoto at AGU M. L. Cherry (LSU), A. Yoshida, T. Sakamoto, Y. Kawakubo, M. Moriyama, Y. Yamada (AGU), K. Yamaoka (Nagoya U), S. Nakahira (JAXA), I. Takahashi (IPMU), Y. Asaoka, S. Ozawa, S. Torii (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U), W. Ishizaki (ICRR), S. Ricciarini (U of Florence), P. S. Marrocchesi (U of Siena) and the CALET collaboration: The long-duration GRB 160419A (Markwardt et al., GCN circ. 19326; Mailyan et al., GCN circ. 19327) triggered the CALET Gamma-Ray Burst Monitor (CGBM) at 15:16:35.4 on 19 April 2016. The burst signal was seen by all CGBM instruments. The light curve of the HXM shows several spikes. The emission starts from T0-2 sec, peaks at T0+3 sec and ends at T0+10 sec. The T90 duration measured by the HXM2 data is 6.2 +- 0.9 sec (50-250 keV). The CGBM data used in this analysis are provided by the Waseda CALET Operation Center located at the Waseda University.