50 research outputs found
Launch of the Space experiment PAMELA
PAMELA is a satellite borne experiment designed to study with great accuracy
cosmic rays of galactic, solar, and trapped nature in a wide energy range
protons: 80 MeV-700 GeV, electrons 50 MeV-400 GeV). Main objective is the study
of the antimatter component: antiprotons (80 MeV-190 GeV), positrons (50
MeV-270 GeV) and search for antimatter with a precision of the order of 10^-8).
The experiment, housed on board the Russian Resurs-DK1 satellite, was launched
on June, 15, 2006 in a 350*600 km orbit with an inclination of 70 degrees. The
detector is composed of a series of scintillator counters arranged at the
extremities of a permanent magnet spectrometer to provide charge,
Time-of-Flight and rigidity information. Lepton/hadron identification is
performed by a Silicon-Tungsten calorimeter and a Neutron detector placed at
the bottom of the device. An Anticounter system is used offline to reject false
triggers coming from the satellite. In self-trigger mode the Calorimeter, the
neutron detector and a shower tail catcher are capable of an independent
measure of the lepton component up to 2 TeV. In this work we describe the
experiment, its scientific objectives and the performance in the first months
after launch.Comment: Accepted for publication on Advances in Space Researc
Status of the GAMMA-400 Project
The preliminary design of the new space gamma-ray telescope GAMMA-400 for the
energy range 100 MeV - 3 TeV is presented. The angular resolution of the
instrument, 1-2{\deg} at E{\gamma} ~100 MeV and ~0.01^{\circ} at E{\gamma} >
100 GeV, its energy resolution ~1% at E{\gamma} > 100 GeV, and the proton
rejection factor ~10E6 are optimized to address a broad range of science
topics, such as search for signatures of dark matter, studies of Galactic and
extragalactic gamma-ray sources, Galactic and extragalactic diffuse emission,
gamma-ray bursts, as well as high-precision measurements of spectra of
cosmic-ray electrons, positrons, and nuclei.Comment: 6 pages, 1 figure, 1 table, submitted to Advances in Space Researc
PAMELA - A Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics
The PAMELA experiment is a satellite-borne apparatus designed to study charged particles in the cosmic radiation with a particular focus on antiparticles. PAMELA is mounted on the Resurs DK1 satellite that was launched from the Baikonur cosmodrome on June 15th 2006. The PAMELA apparatus comprises a time-of-flight system, a magnetic spectrometer, a silicon-tungsten electromagnetic calorimeter, an anticoincidence system, a shower tail catcher scintillator and a neutron detector. The combination of these devices allows antiparticles to be reliably identified from a large background of other charged particles. This paper reviews the design, space qualification and on-ground performance of PAMELA. The in-orbit performance will be discussed in future publications.The PAMELA experiment is a satellite-borne apparatus designed to study charged particles in the cosmic radiation with a particular focus on antiparticles. PAMELA is mounted on the Resurs DK1 satellite that was launched from the Baikonur cosmodrome on June 15th 2006. The PAMELA apparatus comprises a time-of-flight system, a magnetic spectrometer, a silicon-tungsten electromagnetic calorimeter, an anticoincidence system, a shower tail catcher scintillator and a neutron detector. The combination of these devices allows antiparticles to be reliably identified from a large background of other charged particles. This paper reviews the design, space qualification and on-ground performance of PAMELA. The in-orbit performance will be discussed in future publications
The high energy cosmic ray particle spectra measurements with the PAMELA calorimeter
Abstract Up until now there has been limited, contradictive data on the high energy range of the cosmic ray electron-positron, proton and helium spectra. Due to the limitations of the use of a magnetic spectrometer, over 8 years experimental data was processed using information from a sampling electro-magnetic calorimeter, a neutron detector and scintillator detectors. The use of these devices allowed us to successfully obtain the high energy cosmic ray particle spectra measurements. The results of this study clarify previous findings and greaten our understanding of the origin of cosmic rays
Deuteron spectrum measurements under radiation belt with PAMELA instrument
Abstract In this work the results of data analysis of the deuteron albedo radiation obtained in the PAMELA experiment are presented. PAMELA is an international space experiment carried out on board of the satellite Resurs DK-1. The high precision detectors allow to register and identify cosmic ray particles in a wide energy range. The albedo deuteron spectrum in the energy range 70 – 600 MeV/nucleon has been measured
PAMELA Observation of the 2012 May 17 GLE Event
The PAMELA (Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics) satellite-borne experiment has been collecting data in orbit since July 2006, providing accurate measurements of the energy spectra and composition of the cosmic radiation from a few hundred MeVn up to hundred GeVn. This wide interval of measured energies makes PAMELA a unique instrument for Solar Energetic Particle (SEP) observations. Not only does it span the energy range between the ground-based neutron monitor data and the observations of SEPs from space, but also PAMELA carries out the first direct measurements of the composition for the highest energy SEP events, including those causing Ground Level Enhancements (GLEs). PAMELA has registered many SEP events in solar cycle 24 including the 2012 May 17 GLE event (GLE 71), offering unique opportunities to address the question of high-energy SEP origin. Experimental performances and preliminary results on the 2012 May 17 events will be presented. We will discuss the derived particle injection time and compare with other time scales at the Sun including the flare and CME onset times
FIR photoconductivity at filamentary current flow in n-GaAs in a magnetic field
A large number of spectral structures are observed by far infrared magneto-photo-conductivity in n-GaAs at 4.2K biased above impurity breakdown in a regime where current flow is filamentary. Phase changes are found in the center of the 1s−2p+1 line and new structures are observed which shift to higher magnetic fields with increasing bias voltage. The large strength and the intensity dependence of the photosignals indicate that the observed phenomena are due to self-organizing effects of the filament. Small variations of the electron population by infrared irradiation may cause substantial rearrangements of the spatial current distribution