http://export.arxiv.org/pdf/astro-ph/0612718

Wide field aplanatic two-mirror telescopes for ground-based γ-ray astronomy

The Large High Altitude Air Shower Observatory (LHAASO) project is a new generation multi-component instrument, to be built at 4410 meters of altitude in the Sichuan province of China, with the aim to study with unprecedented sensitivity the spec trum, the composition and the anisotropy of cosmic rays in the energy range between 10$^{12}$ and 10$^{18}$ eV, as well as to act simultaneously as a wide aperture (one stereoradiant), continuously-operated gamma ray telescope in the energy range between 10$^{11}$ and $10^{15}$ eV. The experiment will be able of continuously surveying the TeV sky for steady and transient sources from 100 GeV to 1 PeV, t hus opening for the first time the 100-1000 TeV range to the direct observations of the high energy cosmic ray sources. In addition, the different observables (electronic, muonic and Cherenkov/fluorescence components) that will be measured in LHAASO will allow to investigate origin, acceleration and propagation of the radiation through a measurement of energy spec trum, elemental composition and anisotropy with unprecedented resolution. The remarkable sensitivity of LHAASO in cosmic rays physics and gamma astronomy would play a key-role in the comprehensive general program to explore the High Energy Universe. LHAASO will allow important studies of fundamental physics (such as indirect dark matter search, Lorentz invariance violation, quantum gravity) and solar and heliospheric physics. In this document we introduce the concept of LHAASO and the main science goals, providing an overview of the project.

The Large High Altitude Air Shower Observatory (LHAASO) Science White Paper

We provide an updated assessment of the power of the Cherenkov Telescope Array (CTA) to search for thermally produced dark matter at the TeV scale, via the associated gamma-ray signal from pair-annihilating dark matter particles in the region around the Galactic centre. We find that CTA will open a new window of discovery potential, significantly extending the range of robustly testable models given a standard cuspy profile of the dark matter density distribution. Importantly, even for a cored profile, the projected sensitivity of CTA will be sufficient to probe various well-motivated models of thermally produced dark matter at the TeV scale. This is due to CTA's unprecedented sensitivity, angular and energy resolutions, and the planned observational strategy. The survey of the inner Galaxy will cover a much larger region than corresponding previous observational campaigns with imaging atmospheric Cherenkov telescopes. CTA will map with unprecedented precision the large-scale diffuse emission in high-energy gamma rays, constituting a background for dark matter searches for which we adopt state-of-the-art models based on current data. Throughout our analysis, we use up-to-date event reconstruction Monte Carlo tools developed by the CTA consortium, and pay special attention to quantifying the level of instrumental systematic uncertainties, as well as background template systematic errors, required to probe thermally produced dark matter at these energies.

/pdf/sensitivity-of-the-cherenkov-telescope-array-to-a-dark-4c8y7uem4c.pdf

Sensitivity of the Cherenkov Telescope Array to a dark matter signal from the Galactic centre

http://inspirehep.net/record/1263752/files/arXiv:1311.2059.pdf

A Pair Production Telescope for Medium-Energy Gamma-Ray Polarimetry

The sensitivity of the Large Area Telescope (LAT) aboard the Fermi Gamma-ray Space Telescope allows detection of thousands of new gamma-ray sources and detailed characterization of the spectra and variability of bright sources. Unsurprisingly, this increased capability leads to increased complexity in data analysis. Likelihood methods are ideal for connecting models with data, but the computational cost of folding the model input through the multi-scale instrument response function is appreciable. Both interactive analysis and large projects---such as analysis of the full gamma-ray sky---can be prohibitive or impossible, reducing the scope of the science possible with the LAT. To improve on this situation, we have developed pointlike, a software package for fast maximum likelihood analysis of LAT data. It is interactive by design and its rapid evaluation of the likelihood facilitates exploratory and large-scale, all-sky analysis. We detail its implementation and validate its performance on simulated data. We demonstrate its capability for interactive analysis and present several all-sky analyses. These include a search for new gamma-ray sources and the selection of LAT sources with pulsar-like characteristics for targeted radio pulsation searches. We conclude by developing sensitive periodicity tests incorporating spectral information obtained from pointlike.

Likelihood methods for the detection and characterization of gamma-ray pulsars with the Fermi large area telescope

The COS-B experiment for gamma-ray astronomy.

The Cos-B Experiment and Mission

COS-B observations of pulsed gamma -ray emission from PSR 0531+21 and PSR 0833-45.

/pdf/spectral-analysis-of-gamma-rays-with-the-cos-b-satellite-2qyfk8nfz0.pdf

Spectral Analysis of Gamma Rays with the COS-B Satellite

The ESRO satellite COS-B carries one single experiment aiming at the measurement of arrival direction and energy of celestial gamma rays with energies between 25 MeV and 10 GeV. The experiment is conventional in design and consists of a veto counter, a wire spark chamber, a telescope and an energy calorimeter. The energy measurement is obtained by a Csl scintillation crystal of 4.7 radiation length thickness. The expected energy resolution at 100 MeV is 50% FWHM. The other detector elements are designed as to cause the least possible degradation of the energy measurement. The possibilities for the detection of a small contribution of n -origin gamma rays in the presence of a power-law type background spectrum will be discussed.

G. Boella

Papers

The COS-B experiment for gamma-ray astronomy.

The Cos-B Experiment and Mission

COS-B observations of pulsed gamma -ray emission from PSR 0531+21 and PSR 0833-45.

Spectral Analysis of Gamma Rays with the COS-B Satellite

Spectral Analysis of Gamma Rays with the Cos-B Satellite. The Caravane Collaboration