Intermediate GRBs as observed by satellite experiments various satellite experiments I.V. Arkhangelskaja National Research Nuclear University MEPhI (MoscowEngineering Physics Institute)

Gamma-ray bursts duration distribution was the first analyzed using data of BATSE instrument onboard the CGRO. The GRBs duration distribution analysis had shown the existence of two bursts classes: long (t90 more than 2 s) and short (t90 less than 2 s). Kouveliotou C. // Annals of the New York Academy of Sciences, 1995, V. 759, P. 411-415.

GRBs detected by various satellites. Operation period Detector name Energy band Number of GRBs detected b start end Vela satellite series October 1963 March 1972 CsI scintillator counter 0.2 – 1.0 MeV (Vela 5a, 5b) 0.3 – 1.5 MeV (Vela 6a, 6b) 73 VENERA 11- 12 September 1978 April 1980 KONUS [3, 6] 50.0-200 keV 141 Signe 2M (SNEG-2MZ) [3, 7] 80-800 keV ~50 Pioneer Venus Orbiter December 1978 August 1992 Gamma Ray Burst Detector (OGBD) 0.2 to 2.0 MeV ~270 Granat December 1989 December 1996 PHEBUS [9] 102 keV – 1.6 MeV 206 GIGMA [10] 35 – 1300 keV ~90 Ulysses October 1990 June 2009 Solar X-Rays and Cosmic Gamma-Ray Bursts (HUS/GRB) 15.0 - 150 keV (scintillation counters) 5.0 - 15 keV (solid state detectors) 1889 CGRO April 1991 June 2000. BATSE (LAD and SD) [12] 20 keV-2.0 MeV ~2700 OSSE [13] 50 keV-10 MeV Several GRBs COMPTEL [14] 0.7–30 MeV ~30 EGRET (TASCS) [15] 1.0 - 2102 MeV Wind November 1994 operated KONUS 2556 HETE-2 [17] October 2000 March 2006 Fregate 7 - 4102 keV ~300 WXM 2.0-30 keV ~80 SXC 1.5-12 keV INTERGRAL [18] October 2002 Spectrometer SPI 20 keV - 15 MeV Imager IBIS 15 keV - 10 MeV JEM-X 3- 35 keV Suzaku [19]   HXD-WAM 12-300 keV ~750 RHESSI [20] February 2002 February 2010 RHESSI 3 keV–20 MeV 522 [20, 21] Swift November 2004 BAT [22, 23] 15.0 - 150 keV 1128 Agile [24] April, 2007 GRID 30 MeV – 30 GeV Several tens GRBs MCAL 18 – 60 keV Fermi [25] July, 2008 GBM [26] ~8 keV  ~ 30 MeV 1710 LAT [27] ~ 20 MeV to >300 GeV 104

Number of GRBs with defined t90 BATSE/CGRO (LAD and SD) 20 keV-2.0 MeV Year (catalogue) Number of GRBs with defined t90 1991 192 1B, 05.03.92 [3] 219 1992 383 2B, 09.03.93 [4] 436 1993 629 3B, 19.09.94 [5] 835 1994 890 1995 1082 4B, 29.08.96 [6] 1235 1996 1300 1997 1544 1998 1735 1999 1955 2000 4B revised [7] 2049 4B current, 2011 [2] 2056

BAT/Swift 15.0 - 150 keV Year (catalogue) Number of GRBs with defined t90 2004 9 2005 95 2006 197 The first SWIFT BAT Gamma-Ray Burst Catalog 4.09.2007 222 2007 280 2008 381 2009 465 2010 538 The second SWIFT BAT Gamma-Ray Burst Catalog [24], 19.07.2011 458 2011 613 2012 698 9 years Swift BAT Gamma-Ray Burst Catalogue [25] 01.10.2013 753 2013 781 2014 925 2015 960 October 2016 current catalogue 1094 Sept 2016 The Third Swift BAT GRB Catalogue 1047

GBM/Fermi (~8 keV  ~ 30 MeV) Year (catalogue) Number of GRBs with defined t90 2008 123 2009 372 2010 611 2011 827 The Fermi GBM Gamma-Ray Burst catalog: the first two years 01.03.2012 488 2012 1046 2013 1278 The Second Fermi GBM Gamma-Ray Burst catalog: the first four years 06.01.2014 949 2014 1520 2015 1757 April 2016 The Third Fermi GBM GRB Catalog: The First Six Years 1405 Sept 2016 current catalogue Fermi/GBM 1916

Satellite Operation period Detector name Energy band Number of GRBs detected Wind November 1994 operated KONUS 50.0-200 keV 2556 Suzaku   HXD-WAM 12-300 keV ~750 RHESSI February 2002 February 2010 3 keV–20 MeV 522 Unfortunately t90 depends on instrument registered this burst. The detector sensitivity threshold and operation energy band influences to its value. GRBs duration on SWIFT/BAT and Fermi/GBM data for subset of bursts simultaneously registered by these instruments.

GRBs distribution on hardness and duration

Swift 2004 BAT 15.0 - 150 кэВ 200 s 943 Fermi 2008 GBM ~8 кэВ  ~ 30 МэВ 2 s 1883

WIND/VENERA_11-12

Suzaku/HXD-WAM 

GBM/Fermi

GBM/Fermi

Conclusion GRBs observed since 1967 and now several thousands of events were listed in more than 30 catalogues. Gamma-ray bursts duration distribution was first analyzed using data of BATSE instrument onboard the CGRO. The GRBs duration distribution analysis has shown the existence of two bursts classes: long (t90 more than 2 s) and short (t90 less than 2 s). But results of similar distributions analysis for bursts observed by other detectors have shown shifting of boundary between short and long events from value of 2 s. For example, Swift/BAT and RHESSI GRBs subsets analysis gives the value of ~1 s for this separation point. Moreover, t90 depends on instrument registered this burst. The detector sensitivity threshold and operation energy band influences to its value. Therefore, the type of GRB (whether it short or long) should be defined only taking into account distinctive features of instrument detected this event and GRB redshift. After taking into account characteristics GRB duration correction on redshift third intermediate GRBs subgroup appears also in RHESSI, Suzaku, Wind, Fermi/GBM, Swift/BAT burst subset too.

Thank you for attention!

Fermi/GBM events distributions on the Band’s model basic spectral parameters and t90

Fermi/GBM (SBPL)

Fermi/GBM events distribution on the PL model basic a and t90

Fermi (GLAST) наклонение 28. 5, высота 550 Fermi (GLAST) наклонение 28.5, высота 550. GBM 12 сцинтилляционных детекторов NaI, два – BGO; LAT – стриповый детектор с калориметром.

Glast Burst Monitor (GBM / Fermi) ~900 GRB 12 детекторов низкоэнергетического диапазона NAI(TI)  12,7 см h~ 1,27 см Е: 8 кэВ - 2 МэВ 2 детектора высокоэнергетического BGO  12,7 см, h~ 12,7 см Е: 8 кэВ — 10 МэВ

Характеристики орбитальных обсерваторий AGILE и Fermi (GLAST): Обсерватория AGILE Fermi Прибор GRID Super-AGILE MC NaI(Tl) BGO LAT Рабочая поверхность (эффективная), см2 1444 300 ~400 127 12 127 2 8000 Временное разрешение, мкс 2 4 3 <10 Поле зрения, стерадиан 9 2.4 Дапазон энергий, МэВ 30 – 50 000 0,015 – 0,045 0.3 – 100 0,008 – 1 0.15 – 30 20 – 300 000 Исследование проводилось, в основном, по данным обсерватории Fermi, NaI и BGO детекторы предоставляли информацию по низкоэнергетическому диапазону 2 КэВ – 30 МэВ, LAT — по высокоэнергетическому, в дапазоне 20 МэВ – 300 ГэВ.

BATSE GBM порог формирования триггера ~0.2 фот/см2/с 0.61 фот/см2/с Large Area Detectors Low-Energy Detectors сцинтиллятор NaI кол-во 8 12 площадь 2025 см2 126 см2 толщина 1.27 см диапазон 20 кэВ — 2 МэВ 8 кэВ to 2 МэВ Spectroscopy Detectors High-Energy Detectors BGO 2 7.62 см 12.7 см 15 кэВ - 10 МэВ 150 кэВ to 40 МэВ

распределение GRB по длительности для каталога GBM/Fermi

Swift GRBs (274 bursts with known redshift) subset duration distributions without (dotted histogram) and with (solid one) correction on redshift.

Intermediate GRBs subgroup appearance in Swift/BAT distribution on redshift and duration (this subgroup marked by red colour)

Duration distributions for bursts from subsets registered by Fermi/GBM

Fermi/GBM Временной профиль для всплеска GRB090323 z= 3,57 ? Fermi/LAT

080916C 090217 090902B 090323 090328 090626 Два типа жесткого послесвечения GRB: Тип А - max в пределах t90 (“prompt phase”) Тип В - max за пределами t90 (“prompt phase”)

GRB – first detection (1967): observation by detectors sensitive in the range 0.2-1.5 MeV of brief bursts of -rays or high-energy X-rays by Vela 4a (R.W. Klebesadel et al, 1973) The light curve of GRB 670702