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Cosmic Gamma-Ray bursts studies with Ioffe Institute Konus experiments R.L. Aptekar , S.V. Golenetskii , D.D. Frederiks, E.P. Mazets, V.D. Pal’shin Ioffe Institute , Saint Petersburg, Russia.
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Cosmic Gamma-Ray bursts studies with Ioffe Institute Konus experimentsR.L. Aptekar, S.V. Golenetskii, D.D. Frederiks, E.P. Mazets, V.D. Pal’shinIoffe Institute, Saint Petersburg, Russia • Study and analysis of the cosmic gamma-ray bursts from the interplanetary missions Venera 11-14 in 1979-1983: determination of main observational feature of the burts. Soft gamma-repeaters (SGR) were discovered. • Russian-American Konus-Wind experiment: of many years uninterrupted observations of cosmic gamma-ray bursts and soft gamma-repeaters. • Konus-Wind experiment: correlative observations of cosmic gamma-ray bursts with the Kosmos and Coronas spacecraft.The research on the 27 December 2004 flare was the first examlpe of studying Moon-reflected X-ray and gamma-radiation coming from a source outside the Solar System. SGR sources in the galaxies M81 and M31were discovered. • Russian-American Konus-Wind experiment, which has already been operating for more than 17 years, provides important and often unique data regarding the various characteristics of GRBs in the 20 keV to 15 MeV energy range. • Future Ioffe Institute Konus experiments
One of earliest confirmation of the GRB discovery was obtained on January 17, 1972 using the Kosmos-461 data(Mazets et al., JETP Lett., 1973)
The Konus experiments on board the Venera 11 to 14 deep space missions in 1979 to 1983 Left: determination of the source direction of a gamma burst with a system of gamma detectors with anisotropic angular sensitivity; Right: Block diagram of the Konus instrumentation. A sensor system of six scintillation detectors with a close to cosine angular sensitivity pattern arranged along six axes of the spacecraft.
Konus observations of the temporal structures of GRBs revealed of the existence of a separate class of short bursts, demonstrating the so-called «bimodal» duration distribution (Mazets et al., A&Sp.Sci. 1981). The Konus experiments on board the Venera 11 to 14 deep space missions in 1979 to 1983.
The Konus experiments on board the Venera 11 to 14 deep space missions in 1979 to 1983: it was for the first time shown that that the GRB distribution over the celestial sphere is random BАТSЕ, CGRO (Paciesas et al., Ap.J., 1996) Konus, Venera 11-14 deep space missions( Mazets and Golenetskii Astrophys and Space Space Physics Rev., 1988)
The Konus experiments on board the Venera 11 to 14 deep space missions in 1979 to 1983. Observations on Venera 13 and 14 reveal a strong correlations between temporal and spectral behavior of GRBs (Golenetskii et al., Nature, 1983).
The Konus experiments on board the Venera 11 to 14 deep space missions in 1979 to 1983: soft gamma-repeaters were discovered. Giant flare of SGR0526-66was observed on March 5, 1979г.(Mazets et al., , Nature, 1979) Repeated bursts fromSGR0526-66, (Golenetskii et al.,Nature, 1983)
Joint Russian-American Konus-Wind experiment The orbit of s/c excepts an interferences from radiation belts and the Earth shadowing. S/c «Wind», 1994 – up to now
Schematic view of the Konus-Wind gamma-ray detector • The gamma-ray detector is a NaI(Tl) crystal 5 inches in diameter ans 3 inches in hight, placed into a aluminum container with a beryllium entrance window. The crystal scintillator is viewed by a photomultiplier tube through a 20 mm thick lead glass. (Aptekar et al., Space Science Rev.,1995)
Konus-Wind Gamma-Ray Burst Experiment on US GGS-Wind spacecraft • Two detectors S1 and S2: NaI(Tl) 13 cm diameter, 7.5 cm height, 12.5 cm Be entrance window. Located on opposite faces of spacecraft, observing correspondingly the southern and northern celestial hemispheres • Burst mode: Time history analyzer: resolution 2ms – 256 ms, total duration 230s 12 – 50 keV 4096 ch 50 – 200 keV 4096 ch 200 – 770 keV 4096 ch • Pulse Height analyzer: accumulation time 64ms – 8.192 s, duration 79 – 492 s PHA1 12 – 770 keV 63 ch quasilog scale PHA2 0.2 – 10 MeV 63 ch quasilog scale • Background mode: accumulation time 1.47 – 2.94 s Count rate: 12 – 50 keV 50 – 200 keV 200 – 770 keV > 10 MeV
Spectral and temporal analysis of GRBs characteristics detected by Konus-Wind experiment. • Between 1994 November and 2012 May, the Konus-Wind experiment has detected about 2000 GRBs in the trigger mode. Hardness ratios, peak intensities, and temporal parameters, such as (T50, T90) durations and spectral lags are determined for this bursts sample. We argue that T50 is more robust measure for bursts classification than T90. Figures show both types of such distributions for the detected bursts.
Spectral and temporal analysis of GRBs characteristics detected by Konus-Wind experiment. • The discrepancy of long and short GRBs in terms of hardness-duration distribution was analyzed. A comparison was made for 225 bright short GRBs and for 708 bright long GRBs.
Short gamma-ray bursts with extended emission observed with the Konus-Wind experiment. • The existence of “short” gamma-ray bursts accompanied by soft low-intensity emission persisting for tens of seconds was firstly reliably demonstrated in the Konus Catalog in 2002. Later it was confirmed by BAT/Swift instrument and was named extended emission (EE). A comprehensive analysis of short GRBs with EE was performed. It was shown that short GRBs with EE constitute 30% from total number of short GRBs. The initial pulse (left panel) and EE of the burst with the extremely bright EE of GRB070207
The Konus-Wind observations of extremely long gamma-ray burst on April 7, 2008 The extremely long GRB080407 was investigated thoroughly by Konus-Wind experiment together with IPN spacecraft. The observations reveal two distinct emission episodes separated by ~ 1500 s long period of quiescence. The total duration of the burst is about 2100 s. The measured burst fluence is ~ 4x10-4 erg cm-2 .
Simultaneous observations of GRB050717 by Konus-Wind and BAT(Swift) • An intensity and long GRB050717 was observed by Konus-Windin the energy range 21 кэВ – 1300 keV and by BAT-Swiftin the energy range 15-350 keV. The joint spectral fit is presented. This GRB has a record peak energy value Ep=2400 keV. (H. Krimm et al., Ap.J., 2006)
Simultaneous observations of GRB080721 by Konus-Wind and BAT(Swift) • Light curves (left) and joint spectral fit : ВАТ(Swift) in the energy range 15-350 keV и Konus-Windin the energy range 21keV - 7.0 MeV (MNRS, 2009)
Optical and gamma emission of the GRB 050820A, obtained by RAPTORtelescope of Los-Alamos Labotatory (upper picture) and by Konus-Wind experiment (low picture). Both type of radiation was detected simultaneously (Vestrand et al., Nature, 2006). Optical and gamma-radiation of GRBs
Optical andgamma-radiation of GRB080319B The Konus-Wind gamma-ray light curve is presented together with optical data of Tortora telescope. Optical flash begins and ends at about the same times, providing strong evidence that both originate at the same times (Racusin et al., Nature, 2008).
Konus-Wind and Helicon (CORONAS-F) simultaneous observations of giant flare from SGR1806-20 on December 27, 2004 The Konus-Wind detector was evidently saturated for over 1.5 s. The Helicon detector was screened by the Earth from direct exposure of initial pulse of the giant flare, but clearly recorded its reflection from the Moon surface. It allowed, for the first time, reliably reconstructing the temporal profile of the initial pulse of giant flare and determining its energy parameters.
Konus-Wind and Helicon (CORONAS-F) simultaneous observations of giant flare from SGR1806-20 on December 27, 2004 The full isotropic energy releaseQ=2,3х1046 erg and the peak luminosity L=3,5х1047 эрг с-1 (Frederiks et al., Astronomy Lett., 2007)
Konus-Wind observations of GRB 051103 • The light curve of GRB051103 recorded in the energy range 18 – 1100 keV with time resolution of 2 ms. • The burst is in shape of a single pulse with a steep leading edge (≤ 6 ms) and a quasi-exponential decay (τ ~ 50 ms). The total burst duration is ~ 170 ms • The burst had been the brightest GRB observed by Konus-Wind in 11 years, its peak count rate on 2 ms scale in 18 – 1100 keV reached ~ 1.5 x105 s-1
Konus-Wind observations of GRB 051103 • The IPN box of GRB051103 (Golenetskii etal. 2005) is superimposed on 21-cm map of the M81/M82/NGC3077 group and the positions of X-ray sources discovered in the galaxy M81 and its vicinity (Swartz et al. 2003) • The Chandra X-ray observatory surveyed the M81galaxy and revealed 177 X-ray sources with luminosities >1037erg s-1 (Swartz et al. 2003). 14 of then fall within the IPN box. • The values of the fluence and peak flux corresponds to an isotropic energy output Q=7x1046 erg and an isotropic peak luminosity L=4x1048 erg s-1 if the source of GRB051103 is situated in M81/M82 group at D=3.6 Mpc Frederiks et al., Astronomy Letters, 2007 VLA 21cm map: http://www.astro.umass.edu/myun
Konus-Wind observations of GRB 070201 • The light curve of GRB070201 recorded in the energy range 17 – 1130 keV with time resolution of 2 ms • It displays a narrow pulse with a steep leading edge (~ 20 ms) followed by prolonged decay up to 180 ms. • The maximum count rate occurs in a ≤ 2 ms. • The maximum count rate was ~6x105 s-1
Konus-Wind observations of GRB 070201 • UV image of the M31 galaxy (Thilker et al. 2005) and 3σ IPN error box of GRB070201 • Twenty-two sources from an XMM-Newton X-ray survey of M31 fall within the error box (Pietch, 2005) • The values of the fluence and peak flux corresponds to an isotropic energy output Q=1x1045 erg and an isotropic peak luminosity L=1.2x1047 erg s-1 if the source of GRB070201 is situated in M31 at D=780 kpc • Aptekar et al., Ap.J., 2009 GALEX synthesized M31 UV image (Thilker et al. 2005)
Giant flare on 1998 August 27 (SGR 1900+14) • Time and energy characteristics of the August 27 event. • Top: Background subtracted light curve of the outburst. Horizontal sections with triangles specify count rates averaged over the period. The sloped dashed line is a plot of exp(-t/t) for t = 91.5 s. • Bottom: Horizontal sections with squares specify kT averaged over the period. Hurley et al., Nature, 1999
Giant flare on June 18, 1998 (SGR 1627-41) Time and energy characteristics of the June 18 event. Top: Background subtracted light curve of the outburst. Bottom: Spectral evolution during the burst. Mazets et al., Ap.J.L., 1999
Burst series on 1998 May 30 (SGR 1900+14) • 89 days before the giant fare on August 27 • Total fluence (>20keV) S=5.610-5 erg cm-2 [Energy release Q=1.11042 erg] Mazets et al., Astronomy Letters, 1999
Burst series on 5 October 2004 from SGR 1806-20 • 83 days before the giant flare • The series was also detected by INTEGRAL (IBIS/ISGRI) Frederiks et al., Astronomy Letter, 2007
Konus-Wind observations of GRB110918A: it is the mostintense long GRB in the history of Konus-Wind observations since November, 1994 • As observed by Konus-Wind, the burst had a 20-10000 keV fluence of 7.5x10-4 erg/cm2,and 16-ms peak flux of 9.2x10-4 erg/cm2/s. • GRB were observed also by INTEGRAL (SPI-ACS), Mars Odyssey (HEND), and MESSENGER (GRNS). Localized by IPN to the 62 sq arcmin box. A bright X-ray source was found on the edge of the IPN box in Swift/XRT TOO observations which were started ~1.5 days after the trigger. Following the XRT detection, a bright optical counterpart was found (Swift/UVOT, INT, GROND, Gemini-N and more) and it's redshift was determined (z=0.982: Gemini-N, GTC). • The burst intensity allows a precise analysis of the light curves and a fine-scale time-resolved spectral fitting (see Figure). A detailed analysis of the Konus-Wind prompt gamma-ray detection, together with the refined IPN localization and results of the ~50 days-long afterglow monitoring by Swift/XRT and Swift/UVOT can be found soon in the forthcoming paper (Frederiks et al., 2012, in preparation).
Konus-UF is one of the future Ioffe Institute experiments in the field of GRB study. It is planned that Konus-UF will be accomodate on board Spectr-UF space mission (the World Space Observatory) • The Konus-UF instruments consists from two detector units Konus-UF-DS1 and Konus-UF-DS2 and electronic unit Konus-UF-BE. • The each Konus-UF detector will be allocate such manner in order to observe the half of hemisphere. • The energy range of Konus-UF instrument is from 10 keV up to 10 MeV. • The instrument will have a detailed program for measuring of time and spectral characteristics of GRBs. • It is planned that Spectr-UF mission will be launched in 2016 year.
The Konus-UF detector unit drawing The main parts of the detector: 1 – NaI(Tl) cristal 5’’ in diameter by 3’’ in hight, 2 – beryllium entrance window, 4 – lead glass, 6 – photomultiplier, 12, 13, 14 – electronic boards.
Conclusions • The early Konus experiments onboard the Venera 11-14 deep space missions had firstly revealed many of the basic characteristic of GRBs. • Joint Russian-American Konus-Wind experiment, which has already been operating for more than 17 years, provides important and often unique data regarding the various characteristics of GRBs in the 20 keV to 15 MeV energy range. • The Konus-UF experiment is planned for launch in 2016. It will give us an opportunity to continue very effective research into extremely explosive phenomena in the Universe.