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Search Results: 1 - 10 of 627 matches for " for the CTA Consortium "
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Design Concepts for the Cherenkov Telescope Array
The CTA Consortium
Physics , 2010, DOI: 10.1007/s10686-011-9247-0
Abstract: Ground-based gamma-ray astronomy has had a major breakthrough with the impressive results obtained using systems of imaging atmospheric Cherenkov telescopes. Ground-based gamma-ray astronomy has a huge potential in astrophysics, particle physics and cosmology. CTA is an international initiative to build the next generation instrument, with a factor of 5-10 improvement in sensitivity in the 100 GeV to 10 TeV range and the extension to energies well below 100 GeV and above 100 TeV. CTA will consist of two arrays (one in the north, one in the south) for full sky coverage and will be operated as open observatory. The design of CTA is based on currently available technology. This document reports on the status and presents the major design concepts of CTA.
Contributions from the Cherenkov Telescope Array (CTA) Consortium to the ICRC 2011
The CTA Consortium
Physics , 2011,
Abstract: The Cherenkov Telescope Array (CTA) is a project for the construction of a next generation VHE gamma ray observatory with full sky coverage. Its aim is improving by about one order of magnitude the sensitivity of the existing installations, covering about 5 decades in energy (from few tens of GeV to above a hundred TeV) and having enhanced angular and energy resolutions. During 2010 the project became a truly global endeavour carried out by a consortium of about 750 collaborators from Europe, Asia, Africa and the North and South Americas. Also during 2010 the CTA project completed its Design Study phase and started a Preparatory Phase that is expected to extend for three years and should lead to the starting of the construction of CTA. An overview of the CTA Consortium activities project will be given.
CTA contributions to the 2012 Heidelberg Symposium on High Energy Gamma-Ray Astronomy
The CTA Consortium
Physics , 2012,
Abstract: Compilation of CTA contributions to the proceedings of the 2012 Heidelberg Symposium on High Energy Gamma-Ray Astronomy (Gamma 2012), which took place in July 9-13, 2012, in Heidelberg, Germany
CTA - A Project for a New Generation of Cherenkov Telescopes
Michele Doro,for the CTA consortium
Physics , 2009, DOI: 10.1016/j.nima.2010.06.085
Abstract: Gamma-rays provide a powerful insight into the non-thermal universe and perhaps a unique probe for new physics beyond the standard model. Current experiments are already giving results in the physics of acceleration of cosmic rays in supernova remnants, pulsar and active galactic nuclei with almost a hundred sources detected at very-high-energies so far. Despite its relatively recent appearance, very high-energy gamma-ray astronomy has proven to have reached a mature technology with fast assembling, relatively cheap and reliable telescopes. The goal of future installation is to increase the sensitivity by a factor ten compared to current installations, and enlarge the energy domain from few tens of GeV to a hundred TeV. Gamma-ray spectra of astrophysical origin are rather soft thus hardly one single size telescope can cover more than 1.5 decades in energy, therefore an array of telescopes of 2,3 different sizes is required. Hereafter, we present design considerations for a Cherenkov Telescope Array (CTA), a project for a new generation of highly automated telescopes for gamma-ray astronomy. The status of the project, technical solutions and an insight in the involved physics will be presented.
Supernova Remnants and Pulsar Wind Nebulae in the Cherenkov Telescope Array era
M. Renaud,for the CTA Consortium
Physics , 2011,
Abstract: The Cherenkov Telescope Array (CTA) is planned to serve as a ground-based observatory for (very-)high-energy gamma-ray astronomy, open to a wide astrophysics community, providing a deep insight into the non-thermal high-energy universe. It foresees a factor of ~10 improvement in sensitivity above 100 GeV, with substantially better angular and spectral resolutions and wider field-of-view in comparison with currently operational experiments. The CTA consortium is investigating the different physics cases for different proposed array configurations and subsets. Pulsar Wind Nebulae (PWNe), the most numerous VHE Galactic sources, and Supernova Remnants (SNRs), believed to be the acceleration sites of the bulk of cosmic rays, will be two of the main observation targets for CTA. In this contribution, the main scientific goals regarding PWNe and SNRs are discussed, and quantitative examples of the capability of CTA to achieve these objectives are presented.
AGN Physics with the Cherenkov Telescope Array
A. Zech,for the CTA Consortium
Physics , 2012,
Abstract: The Cherenkov Telescope Array (CTA), currently in its Preparatory Phase, will be the first open observatory for very high energy gamma-rays from galactic and extragalactic sources. The international consortium behind CTA is preparing the construction of two large arrays of Cherenkov telescopes in the Northern and Southern Hemispheres with a performance that will be significantly improved compared to the current generation of arrays. Its increased sensitivity and energy range will give CTA access to a large population of Active Galactic Nuclei (AGN) not yet detected at very high energies and provide much more details on known TeV sources. While the low end of the CTA energy coverage will close the current gap with the Fermi-LAT band, its high energy coverage will open a new window on the sky and help us understand the intrinsic shape of the hardest blazar spectra. We outline the current status of CTA and discuss the science case for AGN physics with the observatory. Predictions for source detections based on extrapolations of Fermi-LAT spectra are discussed. An overview is given of prospects for the detection of extended emission from radio galaxies, of rapid variability, and spectral features. The observation of AGN with CTA will also improve current constraints on the distribution of the extragalactic background light, the strength of the intergalactic magnetic field and Lorentz invariance violation.
Lorentz invariance violation with gamma rays
Michael Daniel,for the CTA Consortium
Physics , 2015,
Abstract: The assumption of Lorentz invariance is one of the founding principles of Modern Physics and violation of it would have profound implications to our understanding of the universe. For instance, certain theories attempting a unified theory of quantum gravity predict there could be an effective refractive index of the vacuum; the introduction of an energy dependent dispersion to photons could in turn lead to an observable Lorentz invariance violation signature. Whilst a very small effect on local scales the effect will be cumulative, and so for very high energy particles that travel very large distances the difference in arrival times could become sufficiently large to be detectable. This proceedings will look at testing for such Lorentz invariance violation (LIV) signatures in the astronomical lightcurves of gamma-ray emitting objects, with particular notice being given to the prospects for LIV testing with, the next generation observatory, the Cherenkov Telescope Array.
The next generation Cherenkov Telescope Array observatory: CTA
Stefano Vercellone,for the CTA Consortium
Physics , 2014, DOI: 10.1016/j.nima.2014.04.015
Abstract: The Cherenkov Telescope Array (CTA) is a large collaborative effort aimed at the design and operation of an observatory dedicated to the VHE gamma-ray astrophysics in the energy range 30 GeV-100 TeV, which will improve by about one order of magnitude the sensitivity with respect to the current major arrays (H.E.S.S., MAGIC, and VERITAS). In order to achieve such improved performance, for both the northern and southern CTA sites, four units of 23m diameter Large Size Telescopes (LSTs) will be deployed close to the centre of the array with telescopes separated by about 100m. A larger number (about 25 units) of 12m Medium Size Telescopes (MSTs, separated by about 150m), will cover a larger area. The southern site will also include up to 24 Schwarzschild-Couder dual-mirror medium-size Telescopes (SCTs) with the primary mirror diameter of 9.5m. Above a few TeV, the Cherenkov light intensity is such that showers can be detected even well outside the light pool by telescopes significantly smaller than the MSTs. To achieve the required sensitivity at high energies, a huge area on the ground needs to be covered by Small Size Telescopes (SSTs) with a FOV of about 10 deg and an angular resolution of about 0.2 deg, making the dual-mirror configuration very effective. The SST sub-array will be composed of 50-70 telescopes with a mirror area of about 5-10 square meters and about 300m spacing, distributed across an area of about 10 square kilometers. We will focus on the innovative solution for the optical design of the medium and small size telescopes based on a dual-mirror configuration. This layout will allow us to reduce the dimension and the weight of the camera at the focal plane of the telescope, to adopt SiPMs as light detectors thanks to the reduced plate-scale, and to have an optimal imaging resolution on a wide FOV.
Silicon Photomultiplier Camera for Schwarzschild-Couder Cherenkov Telescopes
J. Vandenbroucke,for the CTA Consortium
Physics , 2014,
Abstract: The Cherenkov Telescope Array (CTA) is an atmospheric Cherenkov observatory that will image the cosmos in very-high-energy gamma rays. CTA will study the highest-energy particle accelerators in the Universe and potentially confirm the particle nature of dark matter. We have designed an innovative Schwarzschild-Couder telescope which uses two mirrors to achieve excellent optical performance across a wide field of view. The small plate scale of the dual-mirror optics enables a compact camera which uses modern technology including silicon photomultipliers and the TARGET application-specific integrated circuit to read out a finely pixelated focal plane of 11,328 channels with modest weight, volume, cost, and power consumption. The camera design is hierarchical and modular at each level, enabling robust construction, operation, and maintenance. A prototype telescope is under construction and will be commissioned at the VERITAS site in Arizona. An array of such telescopes will provide excellent angular resolution and sensitivity in the core energy range of CTA, from 100 GeV to 10 TeV.
Atmospheric considerations for the CTA site search
Stephane Vincent,for the CTA Consortium
Physics , 2014,
Abstract: The Cherenkov Telescope Array (CTA) will be the next high-energy gamma-ray observatory. Selection of the sites, one in each hemisphere, is not obvious since several factors have to be taken into account. Among them, and probably the most crucial, are the atmospheric conditions. Since July 2012, the site working group has deployed automatic ground based instrumentation (ATMOSCOPE) on all the candidate sites. Due to the limited time span available from ground based data, long term weather forecast models become necessary tools for site characterization. It is then of prime importance to validate the models by comparing it to the ATMOSCOPE measurements. We will describe the sources of data (ATMOSCOPE, weather forecasting model and satellite data) for the site evaluation and how they will be used and combined.
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