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New type of long GRBs with additional maxima on the temporal profiles in the high energy gamma-band. A. Zenin, I. Arkhangelskaja, D. Kirin and E. Voevodina National Research Nuclear University “ MEPhI ” Moscow, 2012. High energy gamma-ray bursts observations:. 1991–1999 — CRGO:
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New type of long GRBs with additional maxima on the temporal profiles in the high energy gamma-band A. Zenin, I. Arkhangelskaja, D. Kirin and E. Voevodina National Research Nuclear University “MEPhI” Moscow, 2012 ECRS 2012
High energy gamma-ray bursts observations: 1991–1999 —CRGO: OSSE 0.05–10 MeV COMPTEL 0.7–30 MeV EGRET/TASCS 1-200 MeV EGRET/spark chambers 0.02-30 GeV BATSE (SD&LAD) 0.01-10 MeV 2001–2005 — CORONAS-F: AVS-F 0.1–250 MeV SONG 0.05–150 MeV IRIS 0.1–10 MeV HELICON 0.1–10 MeV • 2007–present day— AGILE: • GRID 0.03-30 GeV • calorimeter (2007) 0.25-200 MeV • 2008–present day — Fermi: • GBM 0.008-40 MeV • LAT 0.1-100 GeV ECRS 2012
Extended high-energy emissionfirst detection: GRB940217 (BATSE trigger №2831, t90 ~150 s.) Gamma-emission (> 50 MeV) up to 1.5 hours after burst starts, maximum registered energy 18GeV (Hurley K et al., 1994, IAU Circ., 5940, 1)
Temporal profiles of GRB 080825C, GRB 090510 and GRB 0909026B. (a) LAT data (Ghisellini G, et al 2010 MN RAS 403 926-37); (b) GBM data.
The temporal profiles of GRB090323, GRB090328 by Fermi/LAT data (Ghisellini G, et al 2010 MN RAS 403 926-37) and Fermi/GBM data. The arrows have shown t90 on GBM data.
The temporal profiles of GRB090626, GRB091031 by Fermi/LAT data (Ghisellini G, et al 2010 MN RAS 403 926-37) and Fermi/GBM data. The arrows have shown t90 on GBM data.
model parameters: A-amplitude, photons-1cm-2keV-1; α- low-energy spectral index; β - high-energy spectral index; Epeak - energy of spectral maximum, keV. if typical spectra: BAND model (Band D et al 1993 ApJ 413 1 281-29) if GRB spectral evolution for GRB910927
gamma-ray burst parameter evolution (data were taken from Bin-Bin Zhang, Bing et al, 2011 arXiv:1009.3338v2) : a) new burst subclass b) “usual” GRB
Conclusion • temporal profiles of GRB090323, GRB090328, GRB090626 and GRB091031 have additional maxima after low-energy t90 intervals finished; • these maxima preceded of faint peaks in low energy bands close to the ends of t90 intervals in low energy band; • parameter evolution are different in comparision to usual gamma-ray bursts. • These features of GRB090323, GRB090328, GRB090626 and GRB091031 allow us to make conclusion that those events could be separated as a new subclass of long bursts with extended high energy γ-emission. • . ECRS 2012
Thank you for attention! ECRS 2012