In this article we discuss the possibility of using the observations by GLAST of standard gamma sources, as the Crab Nebula, to calibrate imaging air Cherenkov detectors, MAGIC in particular, and ...optimise their energy resolution. We show that at around 100
GeV the absolute energy calibration uncertainty of Cherenkov telescopes can be reduced to ≲10% by means of such cross-calibration procedure.
The MAGIC telescope reflecting surface Bigongiari, C.; Bastieri, D.; Galante, N. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2004, Letnik:
518, Številka:
1
Journal Article
Recenzirano
The Major Atmospheric Gamma Imaging Cherenkov telescope will achieve an energy threshold lower than any other present IACT
(E
Th
∼30
Gev)
thanks to the largest reflecting surface, a
17
m
diameter, ...f/1, tessellated parabolic reflector. The tiles are
50
cm×50
cm
all-aluminum spherical mirrors with different radii of curvature to best fit the paraboloid. The technology used to make these mirrors and the method used to measure their optical properties, as the focal length, the spot size and the reflectivity, are described. The results of these measurements are shown.
Gamma ray astronomy is now at the leading edge for studies related both to fundamental physics and astrophysics. The sensitivity of gamma detectors is limited by the huge amount of background, ...constituted by hadronic cosmic rays (typically two to three orders of magnitude more than the signal) and by the accidental background in the detectors. By using the information on the temporal evolution of the Cherenkov light, the background can be reduced. We will present here the results obtained within the MAGIC experiment using a new technique for the reduction of the background. Particle showers produced by gamma rays show a different temporal distribution with respect to showers produced by hadrons; the background due to accidental counts shows no dependence on time. Such novel strategy can increase the sensitivity of present instruments.
A two-level pattern trigger for the MAGIC telescope Bastieri, D.; Bettini, M.; Bigongiari, C. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/2001, Letnik:
461, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Strong scientific motivation are pushing the second generation of ground base Cherenkov telescopes to lower as much as possible their energy threshold. MAGIC will be the biggest single telescope, in ...terms of collection area (250 m
2), foreseen for the second-half of 2001. The large collection area, the new photodetector and the electronic design will allow the telescope to lower the energy threshold below 30
GeV. For this telescope a two-level pattern trigger is designed to work in severe high pixel rate. The MAGIC trigger architecture and its implementation is presented.
Shower reconstruction in the CLUE experiment Bartoli, B.; Bastieri, D.; Bigongiari, C. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/2001, Letnik:
461, Številka:
1
Journal Article
Recenzirano
The CLUE experiment studies primary cosmic rays
(E≥2
TeV)
by detecting UV (190–230 nm) Cherenkov light produced by atmospheric showers. Since atmospheric absorption in the UV range is higher than in ...the visible range, CLUE cannot apply algorithms normally used in IACT
1
1
The Imaging Atmospheric Cherenkov Telescope.
experiments to determine primary cosmic-ray direction. In this paper, we present a new method developed by CLUE. The algorithm performances were evaluated using simulated showers. Preliminary results of the source analysis using this new method are shown.
Commissioning and first tests of the MAGIC telescope Baixeras, C.; Bastieri, D.; Bigongiari, C. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2004, Letnik:
518, Številka:
1
Journal Article
Recenzirano
Major Atmospheric Gamma Imaging Cherenkov telescope is starting its operations with a set of engineering runs to tune the telescope subsystem elements to be ready for the first physics campaign. Many ...technical improvements have been developed and implemented in several elements of the telescope to reach the lowest energy threshold ever obtained by an Imaging Atmospheric Cherenkov Telescope. A general description of the telescope is presented. The commissioning of the telescope's elements is described and the expected performances are reviewed with the final detector set-up.
The authors present the results of a long M 87 monitoring campaign in very high energy ...-rays with the MAGIC-I Cherenkov telescope. They aim to model the persistent non-thermal jet emission by ...monitoring and characterizing the very high energy ...-ray emission of M 87 during a low state. A total of 150 h of data were taken between 2005 and 2007 with the single MAGIC-I telescope, out of which 128.6 h survived the data quality selection. The authors also collected data in the X-ray and Fermi-LAT bands from the literature. No flaring activity was found during the campaign. The source was found to be in a persistent low-emission state, which was at a confidence level of 7 sigma . The extrapolation of the MAGIC spectrum into the GeV energy range matches the previously published Fermi-LAT spectrum well, covering a combined energy range of four orders of magnitude with the same spectral index. (ProQuest: ... denotes formulae/symbols omitted.)
The authors present the discovery of very high energy (VHE) ...-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 ...-rays. They study the VHE ...-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. 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 9.4 sigma . 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 ...-ray flux and the radio flux were comparable in 2010 and 2011. (ProQuest: ... denotes formulae/symbols omitted.)
The high frequency peaked BL Lac PKS 2155-304 with a redshift of z = 0.116 was discovered in 1997 in the very high energy ...-ray range by the University of Durham Mark VI ...-ray Cherenkov telescope ...in Australia with a flux corresponding to 20% of the Crab Nebula flux. It was later observed and detected with high significance by the southern Cherenkov observatory HESS establishing this source as the best studied southern TeV blazar. The authors studied the behavior of the source after its extraordinary flare. Furthermore, they developed an analysis method in order to analyze these data taken under large zenith angles. With Their observations they increased the duty cycle of the source extending the light curve derived by HESS after the outburst. Finally, the authors find night-by-night variability with a maximal amplitude of a factor three to four and an intranight variability in one of the nights MJD 53 945 with a similar amplitude. (ProQuest: ... denotes formulae/symbols omitted.)
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