J. Lund

PAMELA - A Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics

PAMELA is a satellite-borne experiment designed for precision studies of the charged cosmic radiation. The primary scientific goal is the study of the antimatter component of the cosmic radiation (antiprotons, 80 MeV - 190 GeV; and positrons, 50 MeV - 270 GeV) in order to search for evidence of dark matter particle annihilations. PAMELA will also search for primordial antinuclei (in particular, anti-helium), and test cosmic-ray propagation models through precise measurements of the antiparticle energy spectrum and studies of light nuclei and their isotopes. Concomitant goals include a study of solar physics and solar modulation during the 24th solar minimum by investigating low energy particles in the cosmic radiation; and a reconstruction of the cosmic ray electron energy spectrum up to several TeV thereby allowing a possible contribution from local sources to be studied. PAMELA is housed on-board the Russian Resurs-DKl satellite, which was launched on June 15th 2006 in an elliptical (350-600 km altitude) orbit with an inclination of 70 degrees. PAMELA consists of a permanent magnet spectrometer, to provide rigidity and charge sign information; a Time-of-Flight and trigger system, for velocity and charge determination; a silicon-tungsten calorimeter, for lepton/hadron discrimination; and a neutron detector. An anticoincidence system is used offline to reject false triggers. In this article the PAMELA experiment and its status are reviewed. A preliminary discussion of data recorded in-orbit is also presented.

The PAMELA experiment on satellite and its capability in cosmic rays measurements.

The PAMELA equipment will be assembled in 2001 and installed on board the Russian satellite Resurs. PAMELA is conceived mainly to study the antiproton and positron fluxes in cosmic rays up to high ...

The PAMELA experiment in space

We provide in this paper a status report of the space experiment PAMELA. PAMELA aims primarily to measure the flux of antiparticles, namely antiprotons and positrons, in cosmic rays with unpreceden ...

About Separation of Hadron and Electromagnetic Cascades in the Pamela Calorimeter

Results of calibration of the PAMELA instrument at the CERN facilities are discussed. In September, 2003, the calibration of the Neutron Detector together with the Calorimeter was performed with th ...

Random vibration tests of the anticoincidence system of the PAMELA satellite experiment

PAMELA is a general purpose cosmic ray satellite experiment which will be launched early in 2003. An anticoincidence system surrounds the PAMELA silicon tracker to reject particles not clearly entering the acceptance of the experiment. The engineering model of the PAMELA anticounter system uses plastic scintillator which is read out by Hamamatsu R5900U photomultipliers. The anticounters have been subjected to the random vibration spectrum expected during the launch of PAMELA. The integrated amplitude experienced by the photomultipliers was O(20) g RMS. No degradation to the photomultiplier operation or mechanical assembly was observed.

The PAMELA electromagnetic calorimeter: performances

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.