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Title: IREM Observations of the Initial Spike from the SGR1806-20 Giant Flare

Abstract

Main spike of the giant flare from SGR1806-20 (27 Dec 04) released enormous energy that saturated most X-ray detectors onboard satellites. Fortunately, several smaller instruments dedicated mainly for charged particle detection could gather reliable data. To date, spike fluences from various detectors agree within a factor of 3 while the spectra are described using different formulas. To the analysis performed with particle detectors from RHESSI and Wind we add new data provided by IREM monitor onboard of INTEGRAL. It supports cooling blackbody spectrum with temperature of 230{+-}50 keV and energy of 0.97{+-}0.50 erg/cm2.

Authors:
; ;  [1];  [2]; ; ;  [3];  [4];  [5];  [6];  [7]
  1. Paul Scherrer Institut, CH-5232 PSI Villigen (Switzerland)
  2. University of California, Santa Cruz, Santa Cruz, CA 95064 (United States)
  3. European Space Operation Center ESA/ESOC, 64293 Darmstadt (Germany)
  4. University of California, Berkeley, California 94720 (United States)
  5. UC Berkeley Space Science Laboratory, Berkeley, California 94720-7450 (United States)
  6. European Space Research and Technology Centre ESA/ESTEC, 2200 AG Noordwijk (Netherlands)
  7. INTEGRAL Science Data Centre, CH-1290 Versoix (Switzerland)
Publication Date:
OSTI Identifier:
20719681
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 801; Journal Issue: 1; Conference: Conference on astrophysical sources of high energy particles and radiation, Torun (Poland), 20-24 Jun 2005; Other Information: DOI: 10.1063/1.2141886; (c) 2005 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; CHARGED PARTICLE DETECTION; GAMMA DETECTION; KEV RANGE 100-1000; NEUTRON STARS; SATELLITES; X-RAY DETECTION

Citation Formats

Hajdas, W., Wigger, C., Buehler, P., Smith, D. M., Bergogne, O., Di Marco, F., Schmidt, M., Boggs, S., Hurley, K., Mohhamadzadeh, A., and Produit, N.. IREM Observations of the Initial Spike from the SGR1806-20 Giant Flare. United States: N. p., 2005. Web. doi:10.1063/1.2141886.
Hajdas, W., Wigger, C., Buehler, P., Smith, D. M., Bergogne, O., Di Marco, F., Schmidt, M., Boggs, S., Hurley, K., Mohhamadzadeh, A., & Produit, N.. IREM Observations of the Initial Spike from the SGR1806-20 Giant Flare. United States. doi:10.1063/1.2141886.
Hajdas, W., Wigger, C., Buehler, P., Smith, D. M., Bergogne, O., Di Marco, F., Schmidt, M., Boggs, S., Hurley, K., Mohhamadzadeh, A., and Produit, N.. Tue . "IREM Observations of the Initial Spike from the SGR1806-20 Giant Flare". United States. doi:10.1063/1.2141886.
@article{osti_20719681,
title = {IREM Observations of the Initial Spike from the SGR1806-20 Giant Flare},
author = {Hajdas, W. and Wigger, C. and Buehler, P. and Smith, D. M. and Bergogne, O. and Di Marco, F. and Schmidt, M. and Boggs, S. and Hurley, K. and Mohhamadzadeh, A. and Produit, N.},
abstractNote = {Main spike of the giant flare from SGR1806-20 (27 Dec 04) released enormous energy that saturated most X-ray detectors onboard satellites. Fortunately, several smaller instruments dedicated mainly for charged particle detection could gather reliable data. To date, spike fluences from various detectors agree within a factor of 3 while the spectra are described using different formulas. To the analysis performed with particle detectors from RHESSI and Wind we add new data provided by IREM monitor onboard of INTEGRAL. It supports cooling blackbody spectrum with temperature of 230{+-}50 keV and energy of 0.97{+-}0.50 erg/cm2.},
doi = {10.1063/1.2141886},
journal = {AIP Conference Proceedings},
number = 1,
volume = 801,
place = {United States},
year = {Tue Nov 22 00:00:00 EST 2005},
month = {Tue Nov 22 00:00:00 EST 2005}
}
  • The formation of an expanding, moving, and fading radio source. We report observations of this radio source with the Multi-Element Radio-Linked Interferometer Network (MERLIN) and the Very Long Baseline Array (VLBA). The observations confirm the elongation and expansion already reported based on observations at lower angular resolutions, but suggest that at early epochs the structure is not consistent with the very simplest models such as a smooth flux distribution. In particular there appears to be significant structure on small angular scales, with {approx}10% of the radio flux arising on angular scales <= 100 milliarcsec. This structure may correspond to localizedmore » sites of particle acceleration during the early phases of expansion and interaction with the ambient medium.« less
  • The multi-wavelength observations of the 2004 December 27 Giant Flare (GF) from SGR 1806-20 and its long-lived radio afterglow are briefly reviewed. The GF appears to have been produced by a dramatic reconfiguration of the magnetic field near the surface of the neutron star, possibly accompanied by fractures in the crust. The explosive release of over 10{sup 46} erg (isotropic equivalent) powered a one-sided mildly relativistic outflow. The outflow produced a new expanding radio nebula, that is still visible over a year after the GF. Also considered are the constraints on the total energy in the GF, the energy andmore » mass in the outflow, and on the external density, as well as possible implications for short {gamma}-ray bursts and potential signatures in high energy neutrinos, photons, or cosmic rays. Some possible future observations of this and other GFs are briefly discussed.« less
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  • On 27 December 2004, a giant {gamma} flare from the Soft Gamma-Ray Repeater 1806-20 saturated many satellite gamma-ray detectors, being the brightest transient event ever observed in the Galaxy. AMANDA-II was used to search for down-going muons indicative of high-energy gammas and/or neutrinos from this object. The data revealed no significant signal, so upper limits (at 90% C.L.) on the normalization constant were set: 0.05(0.5) TeV{sup -1} m{sup -2} s{sup -1} for {gamma}=-1.47 (-2) in the gamma flux and 0.4(6.1) TeV{sup -1} m{sup -2} s{sup -1} for {gamma}=-1.47 (-2) in the high-energy neutrino flux.
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