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Title: Prompt VHE Observations of GRBs by MAGIC

Abstract

MAGIC is the fastest slewing Cherenkov telescope, with re-pointing capabilities of 20 - 40 s compared with the {approx} 10 min. of HESS and the few degrees per minute of VERITAS. Since the beginning of the GRB observation (April 2005) it observed a dozen of GRBs and set upper limits on their VHE emission. Most of them were triggered by SWIFT and have therefore quite a large z value. This can be one of the reasons why only upper limits could be set. As MAGIC has the lowest energy threshold among Cherenkov telescopes partially overlapping with GLAST, the simultaneous observation of GRBs by GLAST and MAGIC allows a continuous observation from 10 keV to 10 TeV.

Authors:
 [1];  [2]
  1. Dipartimento di Fisica - Universita di Padova, Via Marzolo 8 - 35131 Padova (Italy)
  2. (Italy)
Publication Date:
OSTI Identifier:
21057316
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 906; Journal Issue: 1; Conference: Stockholm symposium on GRB's: Gamma-ray bursts prospects for GLAST, Stockholm (Sweden), 1 Sep 2006; Other Information: DOI: 10.1063/1.2737417; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA). MAGIC Collaboration
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; CHERENKOV COUNTERS; COSMIC GAMMA BURSTS; COSMIC GAMMA SOURCES; COSMIC PHOTONS; GAMMA ASTRONOMY; GAMMA RADIATION; PHOTON EMISSION; TELESCOPE COUNTERS; TEV RANGE

Citation Formats

Bastieri, Denis, and INFN Sezione di Padova, Via Marzolo 8 - 35131 Padova. Prompt VHE Observations of GRBs by MAGIC. United States: N. p., 2007. Web. doi:10.1063/1.2737417.
Bastieri, Denis, & INFN Sezione di Padova, Via Marzolo 8 - 35131 Padova. Prompt VHE Observations of GRBs by MAGIC. United States. doi:10.1063/1.2737417.
Bastieri, Denis, and INFN Sezione di Padova, Via Marzolo 8 - 35131 Padova. Tue . "Prompt VHE Observations of GRBs by MAGIC". United States. doi:10.1063/1.2737417.
@article{osti_21057316,
title = {Prompt VHE Observations of GRBs by MAGIC},
author = {Bastieri, Denis and INFN Sezione di Padova, Via Marzolo 8 - 35131 Padova},
abstractNote = {MAGIC is the fastest slewing Cherenkov telescope, with re-pointing capabilities of 20 - 40 s compared with the {approx} 10 min. of HESS and the few degrees per minute of VERITAS. Since the beginning of the GRB observation (April 2005) it observed a dozen of GRBs and set upper limits on their VHE emission. Most of them were triggered by SWIFT and have therefore quite a large z value. This can be one of the reasons why only upper limits could be set. As MAGIC has the lowest energy threshold among Cherenkov telescopes partially overlapping with GLAST, the simultaneous observation of GRBs by GLAST and MAGIC allows a continuous observation from 10 keV to 10 TeV.},
doi = {10.1063/1.2737417},
journal = {AIP Conference Proceedings},
number = 1,
volume = 906,
place = {United States},
year = {Tue May 01 00:00:00 EDT 2007},
month = {Tue May 01 00:00:00 EDT 2007}
}
  • Here, we present the discovery of very high energy (VHE, E > 100 GeV) γ-ray emission from the BL Lac object 1ES 1215+303 by the MAGIC telescopes and simultaneous multi-wavelength data in a broad energy range from radio to γ-rays. We also study the VHE γ-ray emission from 1ES 1215+303 and its relation to the emissions in other wavelengths. Triggered by an optical outburst, MAGIC observed the source in 2011 January - February for 20.3 h. The target was monitored in the optical R-band by the KVA telescope that also performed optical polarization measurements. Furthermore, we triggered target of opportunitymore » observations with the Swift satellite and obtained simultaneous and quasi-simultaneous data from the Fermi Large Area Telescope and from the Metsähovi radio telescope. We also present the analysis of older MAGIC data taken in 2010. The MAGIC observations of 1ES 1215+303 carried out in 2011 January - February resulted in the first detection of the source at VHE with a statistical significance of 9.4σ. Simultaneously, the source was observed in a high optical and X-ray state. In 2010 the source was observed in a lower state in optical, X-ray, and VHE, while the GeV γ-ray flux and the radio flux were comparable in 2010 and 2011. The spectral energy distribution obtained with the 2011 data can be modeled with a simple one zone SSC model, but it requires extreme values for the Doppler factor or the electron energy distribution.« less
  • Owing to prompt identifications of GRBs by Swift, the importance of prompt observations by ground-based telescopes has recently increased. Multiwavelength observations are also important ever before because chromatic temporal variations have been reported in several early afterglows. Ground-based observations with 1-m class optical-infrared telescopes are, however, inadequate in terms of the prompt observation. High energy gamma-ray observations are also inadequate in terms of the multiwavelength studies. Our group has 'KANATA', the 1.5-m optical-infrared telescope whose characteristic is a high driving speed. We also join projects of the Wide-band All-sky Monitor (WAM) and the Gamma-ray Large Area Space Telescope (GLAST). Withmore » these instruments, we are developing a prompt observation system for optical-infrared afterglows with KANATA and a system for the analysis of multiwavelength data. The prompt observation system will be able to observe GRBs typically within a minute. The multiwavelength system can get GRB spectra with a wide coverage of wavelengths from optical to GeV gamma-ray region. In this paper, we introduce outlines of prompt and multiwavelength observation systems that we constructed. We report our initial results and obtainable results.« less
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