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The GAMMA-400 gamma-ray telescope is designed to measure the fluxes of gamma-rays and cosmic-ray electrons + positrons, which can be produced by annihilation or decay of the dark matter particles, as well as to survey the celestial sphere in order to study point and extended sources of gamma-rays, measure energy spectra of Galactic and extragalactic diffuse gamma-ray emission, gamma-ray bursts, and gamma-ray emission from the Sun. GAMMA-400 covers the energy range from 100 MeV to 3000 GeV. Its angular resolution is ∼0.01° (Eγ > 100 GeV), the energy resolution ∼1% (Eγ > 10 GeV), and the proton rejection factor ∼106. GAMMA-400 will be installed on the Russian space platform Navigator. The beginning of observations is planned for 2018. [ABSTRACT FROM AUTHOR]

On the 15th of June 2006, the PAMELA satellite-borne experiment was launched from the Baikonur cosmodrome and it has been collecting data since July 2006. The instrument allows precision studies of the charged cosmic radiation to be conducted over a wide energy range (100 MeV–100’s GeV) with high statistics. The primary scientific goal is the measurement of the antiproton and positron energy spectrum in order to search for exotic sources, such as dark matter particle annihilations. PAMELA is also searching for primordial antinuclei (anti-helium), and testing cosmic-ray propagation models through precise measurements of the antiparticle energy spectrum and precision studies of light nuclei and their isotopes. Moreover, PAMELA is investigating phenomena connected with solar and earth physics. Results of the antiproton and positron data will be presented. [ABSTRACT FROM AUTHOR]

On the 15th of June 2006, the PAMELA satellite-borne experiment was launched from the Bajkonur cosmodrome and since July 2006 it has been collected data. The core of the apparatus is a silicon-microstrip magnetic spectrometer combined with a time-of-flight system, a silicon-tungsten electromagnetic calorimeter, an anticoincidence system, a shower tail counter scintillator and a neutron detector. The overall devices allow precision studies of the charged cosmic radiation to be conducted over a wide energy range (100 MeV–100’s GeV) with high statistics. The primary scientific goal is the measurement of the antiproton and positron energy spectra in order to search for exotic sources, such as dark matter particle annihilation. PAMELA is also searching for primordial antinuclei (He). Concomitant, but not secondary, goals are the measurements of light nuclei and their isotopes for studying the energy dependence of cosmic ray lifetimes in the Galaxy, the monitoring of the solar activity and the study of the radiation belts. [ABSTRACT FROM AUTHOR]

A sampling silicon-tungsten imaging calorimeter has been designed and built for the PAMELA satellite-borne experiment. The calorimeter has been designed to identify antiprotons from an electron background and positrons in a background of protons with a high efficiency and rejection power. In this work we present the identification capabilities of the calorimeter obtained using both Monte Carlo and test beam data. We show that the calorimeter provides a proton rejection factor of at least 105 while keeping a high efficiency in selecting electrons and positrons. Hence, the calorimeter will fulfill the identification power needed to reach the primary scientific objectives of PAMELA, that are the measurement of the flux of antiprotons, positrons and light isotopes in the cosmic radiation. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Silicon Drift Detectors (SDDs) are well suited to high-energy physics experiments with relatively low event rates. In particular SDDs will be used for the two intermediate layers of the Inner Tracking System of the ALICE experiment. Beam test results of linear SDD prototypes have shown a resolution of 40×30 µm[sup 2] and a cluster finding efficiency of essentially 100% with E=600 V/cm. [ABSTRACT FROM AUTHOR]

Only a few charge preamplifiers suitable for use with Large Area Silicon Detectors have been realised as integrated circuits. In this paper we presents some of them that includes in the same chip both a charge preamplifier and a shaper, dramatically cutting power dissipation, size and cost. The resolution achieved is very good. It is intended in particular for use in Intermediate Energy Physics Experiments. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We present here a concept for a light and low-power wide field monitor working in the X-ray range, suitable for simultaneous imaging of large portions of the sky and GRB localizations. Our concept evolves from and improves on the design of the 5-kg SuperAGILE experiment, flying on the AGILE mission and currently delivering arcmin-localizations of GRBs at a rate of about 1/month. Similar to SuperAGILE, our concept is based on position sensitive silicon detectors equipped with one-dimensional coded masks. Different options are available for the detector, whose properties, combined with the scientific requirements, drive the design of the experiment. Our approach is based on a modular detector. The experiment design can then be tailored to specific scientific goals of the experiment or the mission (e.g., to cite GRBs only: the brightest GRBs/XRFs on a large field of view—FoV, or many low-fluence GRBs/XRFs on a smaller FoV, or the low energy spectrum of the prompt event, or the detection of high-z GRBs). In this paper we describe the concept, the main detector properties and outline some possible experiment configurations, with examples of their expected performance. Different experiment configurations in terms of area, FoV, angular resolution may be designed starting from the same detectors. Instead, the band-pass is mostly related to the detector properties. A key point of our project is the high degree of readiness of the detectors that are at production level and may be immediately proposed for a future experiment onboard missions with high readiness requirements. [ABSTRACT FROM AUTHOR]

We present a concept for a coded-mask All Sky Monitor based on Silicon Drift Detectors. The current design has a high level of readiness, minimizes the total weight (<10 kg for each 1-D module with a sensitive area of ∼500 cm2) and power consumption (<10 W per module). In this configuration it is sensitive in the range 3–60 keV, has a fully coded field of view of >2 steradians and an on-axis sensitivity of ∼3 mCrab (5σ, 50 ks). The intrinsic modularity of the detector allows to envisage experiments with different configurations, in terms of field of view, angular resolution or effective area. We show the expected scientific performances of such an experiment, with emphasis on the observations of X-ray Galactic transients and gamma-ray bursts. [ABSTRACT FROM AUTHOR]