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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.

The PAMELA satellite experiment has measured the cosmic-ray positron fraction between 1.5 GeV and 100 GeV. The need to reliably discriminate between the positron signal and proton background has required the development of an ad hoc analysis procedure. In this paper, a method for positron identification is described and its stability and capability to yield a correct background estimate is shown. The analysis includes new experimental data, the application of three different fitting techniques for the background sample and an estimate of systematic uncertainties due to possible inaccuracies in the background selection. The new experimental results confirm both solar modulation effects on cosmic-rays with low rigidities and an anomalous positron abundance above 10 GeV.

This paper presents precise measurements of the differential energy spectra of quasi-trapped secondary electrons and positrons and their ratio between 80 MeV and 10 GeV in the near-equatorial regio ...

We present a review of the experimental results obtained by PAMELA in measuring the and e± abundance in cosmic rays. In this context, we discuss the interpretation of the observed anomalous positron excess in terms of the annihilation of dark matter particles as well as in terms of standard astrophysical sources. Moreover we show the constraints on dark matter models from data.

The PAMELA experiment is a satellite-borne apparatus designed to study charged particles in the cosmic radiation, with a particular focus on antiparticles. The detector is housed on the Resurs-DK1 satellite and it is taking data since June 2006. The main parts of the apparatus are a magnetic spectrometer, which is equipped with a silicon-microstrip tracking system and which is used to measure the rigidity and the charge of particles, and a silicon/tungsten electromagnetic calorimeter which provides particle identification. The main results about the antiparticles component of cosmic rays obtained during the first 500 days of data taking are summarized here.

Antiparticles account for a small fraction of cosmic rays and are known to be produced in interactions between cosmic-ray nuclei and atoms in the interstellar medium1, which is referred to as a 'secondary source'. Positrons might also originate in objects such as pulsars2 and microquasars3 or through dark matter annihilation4, which would be 'primary sources'. Previous statistically limited measurements5, 6, 7 of the ratio of positron and electron fluxes have been interpreted as evidence for a primary source for the positrons, as has an increase in the total electron+positron flux at energies between 300 and 600 GeV (ref. 8). Here we report a measurement of the positron fraction in the energy range 1.5–100 GeV. We find that the positron fraction increases sharply over much of that range, in a way that appears to be completely inconsistent with secondary sources. We therefore conclude that a primary source, be it an astrophysical object or dark matter annihilation, is necessary.

The SiPMs are excellent candidates for the replacement of PMTs in many experimental situations. In this article we describe the performances of different types of SiPMs from Hamamatsu and FBK-IRST before and after irradiation with photons and neutrons in terms of signal to noise ratio, time resolution and efficiency. The SiPMs are connected to a scintillation tracker/calorimeter, composed of eight layers ( 4 x and 4 y ) of 10 scintillating bars each and have been tested at the CERN PS T9 beamline. The tracker/calorimeter is a small-size prototype of a bigger detector called EMR (Electron Muon Ranger), a particle identification system developed for the MICE experiment.

The PAMELA experiment is being carried out on board the Russian satellite Resurs DK1 placed in the near-earth near-polar orbit on June 15, 2006. The apparatus comprising a silicon-strip magnetic sp ...

A new measurement of the cosmic-ray antiproton-to-proton flux ratio between 1 and 100 GeV is presented. The results were obtained with the PAMELA experiment, which was launched into low-Earth orbit on-board the Resurs-DK1 satellite on June 15th 2006. During 500 days of data collection a total of about 1000 antiprotons have been identified, including 100 above an energy of 20 GeV. The high-energy results are a tenfold improvement in statistics with respect to all previously published data. The data follow the trend expected from secondary production calculations and significantly constrain contributions from exotic sources, e. g., dark matter particle annihilations.

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.

The Payload for Antimatter-Matter Exploration and Light Nuclei Astrophysics (PAMELA), primarily designed to directly measure antiparticles (antiprotons and positrons) in the cosmic radiation, was l ...

Antiparticles account for a small fraction of cosmic rays and are known to be produced in interactions between cosmic-ray nuclei and atoms in the interstellar medium(1), which is referred to as a 'secondary source'. Positrons might also originate in objects such as pulsars(2) and microquasars(3) or through dark matter annihilation(4), which would be 'primary sources'. Previous statistically limited measurements(5-7) of the ratio of positron and electron fluxes have been interpreted as evidence for a primary source for the positrons, as has an increase in the total electron+positron flux at energies between 300 and 600 GeV (ref. 8). Here we report a measurement of the positron fraction in the energy range 1.5-100 GeV. We find that the positron fraction increases sharply overmuch of that range, in a way that appears to be completely inconsistent with secondary sources. We therefore conclude that a primary source, be it an astrophysical object or dark matter annihilation, is necessary.

The PAMELA experiment is a satellite-borne apparatus designed to study charged particles in the cosmic radiation, with a particular focus on antiparticles. The detector is housed on the Resurs-DK1 satellite and it is taking data since June 2006. The main parts of the apparatus are a magnetic spectrometer, which is equipped with a silicon-microstrip tracking system and which is used to measure the rigidity and the charge of particles, and a silicon/tungsten electromagnetic calorimeter which provides particle identification. The main results about the antiparticles component of cosmic rays obtained during the first 500 days of data taking are summarized here.

The PAMELA (a Payload for Antimatter-Matter Exploration and Light-nuclei Astrophysics) space mission has been launched on-board the Resurs-DK1 satellite on June 15(th) 2006 from the Baikonur cosmodrome, in Kazakhstan. PAMELA is a particle spectrometer designed to study charged particles in the cosmic radiation with special focus on the investigation of the nature of dark matter, by mean of the measure of the cosmic-ray antiproton and positron spectra over the largest energy range ever achieved.

This paper presents precise measurements of the differential energy spectra of quasi-trapped secondary electrons and positrons and their ratio between 80 MeV and 10 GeV in the near-equatorial region (altitudes between 350 km and 600 km). Latitudinal dependences of the spectra are analyzed in detail. The results were obtained from July until November 2006 onboard the Resurs-DK satellite by the PAMELA spectrometer, a general purpose cosmic ray detector system built around a permanent magnet spectrometer and a silicon-tungsten calorimeter.

The PAMELA (a Payload for Antimatter-Matter Exploration and Light-nuclei Astrophysics) space mission has been launched on-board the Resurs-DK1 satellite on June 15(th) 2006 from the Baikonur cosmod ...

Phase contrast x-ray imaging is a powerful technique for the detection of low-contrast details in weakly absorbing objects. This method is of possible relevance in the field of diagnostic radiology. In fact, imaging low-contrast details within soft tissue does not give satisfactory results in conventional x-ray absorption radiology, mammography being a typical example. Nevertheless, up to now all applications of the phase contrast technique, carried out on thin samples, have required radiation doses substantially higher than those delivered in conventional radiological examinations. To demonstrate the applicability of the method to mammography we produced phase contrast images of objects a few centimetres thick while delivering radiation doses lower than or comparable to doses needed in standard mammographic examinations (typically approximately 1 mGy mean glandular dose (MGD)). We show images of a custom mammographic phantom and of two specimens of human breast tissue obtained at the SYRMEP bending magnet beamline at Elettra, the Trieste synchrotron radiation facility. The introduction of an intensifier screen enabled us to obtain phase contrast images of these thick samples with radiation doses comparable to those used in mammography. Low absorbing details such as 50 microm thick nylon wires or thin calcium deposits (approximately 50 microm) within breast tissue, invisible with conventional techniques, are detected by means of the proposed method. We also find that the use of a bending magnet radiation source relaxes the previously reported requirements on source size for phase contrast imaging. Finally, the consistency of the results has been checked by theoretical simulations carried out for the purposes of this experiment.

The SYRMEP (SYnchrotron Radiation for MEdical Physics) collaboration is presently taking data at a beamline at the synchrotron ELETTRA in Trieste to study the performances of a digital silicon pixel imaging system for mammography. Images are obtained with a scanning technique in the energy range 15–30 keV. The readout electronics operates in a single photon counting mode with a photon rate of about 10 6 /( mm 2 s ) , which is still 4 times lower than the maximum rate reachable with the present beamline configuration. Two different detector layouts have been designed, the first one consisting of a single-layer silicon microstrip detector positioned edge-on with respect to the beam, and the second innovative one represented by a matrix of these detectors stacked to cover the full beam dimension (100×4 mm 2 ) . We present here the results obtained with a single-layer detector and a double-layer detector (both 5 cm wide) with mammographic phantoms and human breast tissue.

PAMELA is a satellite-borne experiment designed to study with great accuracy charged particles in the cosmic radiation with a particular focus on antiparticles. The experiment, housed on board the Russian Resurs-DK1 satellite, was launched on June 15, 2006 in a 350×600km orbit with an inclination of 70. The apparatus comprises a time-of-flight system, a silicon-microstrip 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 charged particle identification over a wide energy range. In this work, the detector design is reviewed and the in-orbit performances in the first months after the launch are presented.

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., Accepted for publication on Advances in Space Research

A synchrotron radiation beamline devoted to medical imaging has been built by the SYRMEP collaboration at Elettra in Trieste, Italy, and is now in operation. The SYRMEP imaging system is based on the combination of a monochromatic, laminar X-ray beam, with a laminar, high-efficiency pixel silicon detector. To image soft tissue, including small, low-contrast details, as in mammography, beam energies should be chosen in the range from 15 keV to 30 keV and the detector should be capable of single-photon counting. The SYRMEP beamline originates from a bending magnet light port and consists basically of a Be window, a slit system and a Si(1,1,1) crystal monochromator. The experimental area is equipped with a radiation flux monitor, a sample movement stage, and a positioning system holding the silicon detector. Images are obtained by keeping the detector stationary with respect to the beam and by scanning the sample through the beam itself. The current detector is a linear array of 200/spl times/300 /spl mu/m/sup 2/ pixels, each coupled to its electronic counting chain on a custom VLSI read-out chip. We present a summary of beam studies, and digital images of standard RMI 160 and RMI 180 Ackermann Mammographic phantoms. Results show the high contrast resolution, the good spatial resolution and the large dynamic range which constitute the defining characteristics of the SYRMEP imaging system.

In the framework of the INFN R&D projects CASIS and CASIS2, we are developing a new-concept VLSI front-end chip for the read-out of silicon calorimeters for high-energy astroparticle physics experiments. The ASIC has an input dynamic range of 52.6 pC (~ 11000 minimum ionizing particle, MIP) and features a new Charge Sensitive Amplifier (CSA) architecture, which uses a real-time automatic gain selection circuitry to switch between the input ranges of [0 divide 500 MIP] and [0 - 11000 MIP]. Following the CSA, a Correlated Double Sampling (CDS) shaper completes the front-end part. The final objective is to design and realize by 2008 a 16-channel chip with digitized outputs, which integrates one 12-bit Cyclic ADC per channel. We report on the design and tests of the second prototype (CASIS1.1) of the chip, which includes a revised and improved version of the Cyclic ADC with respect to that implemented in the first prototype (CASIS1.0).

The satellite-borne experiment PAMELA has been used to make new measurements of cosmic ray H and He isotopes. The isotopic composition was measured between 100 and 600 MeV/n for hydrogen and between 100 and 900 MeV/n for helium isotopes over the 23rd solar minimum from July 2006 to December 2007. The energy spectrum of these components carries fundamental information regarding the propagation of cosmic rays in the galaxy which are competitive with those obtained from other secondary to primary measurements such as B/C., 11 pages, 11 figures, 5 tables. To appear in Astrophysical Journal

The PAMELA project is the satellite experiment for measurements of the cosmic ray energy spectra in a wide energy range in near-Earth space. The PAMELA apparatus is in orbit from 2006 till today. The calorimeter is the main part of the instrument. It is able to measure energy, to distinguish between hadrons and electrons and to reconstruct the arriving particle direction. Using of special triggers for the calorimeter allows significant increasing of statistics. In consideration of these facts the technique of anisotropy searching in the energy range extending higher than 10 GeV has been developed. This technique is based on the calorimeter data and has as content the advanced method of the reconstruction of the secondary particle shower axis in the calorimeter.

The PAMELA magnetic spectrometer launched in June 2006 has observed the last strong energetic solar particle event of the 23rd solar cycle in December 2006. Subsequent long minimum of solar activity and weak development of the 24th solar cycle led to a deficit in the solar energetic particle events on the Earth orbit. As a result, only few events with protons accelerated above 100 MeV occurred in 2010-2012. The paper gives the preliminary results on energetic solar particles in the beginning of the 24th solar circle as measured with the PAMELA instrument.

Spectrometers PAMELA and ARINA, mounted on the spacecraft Resurs-DK1, carried out precision measurements of galactic cosmic ray (GCR) flux near the Earth from 2006 to present. Combining these instruments gives the possibility to study the effect of solar modulation in the energy range from 30 MeV to dozens of GeV. This report presents experimental results concerning the time interval from the end of the 23rd solar cycle (noted by an prolonged minimum) to the beginning of the 24th cycle. The cosmic ray flux raised up to the end of 2009, then it began to decline, which is in coincidence with the sunspot number and evidence of the solar activity increasing. Some additional features were noted in the time profile of galactic cosmic ray flux, which, as shown by analysis of the correlation, correspond to a change of such heliospheric parameters as the tilt angle of the heliospheric current sheet (HCS), the solar wind velocity and the intensity of interplanetary magnetic field (IMF).

In the last few years the interest for application of silicon radiation detectors to the detection of X-rays in the 15–30 keV region has been growing. One of the main reasons of such an interest is the development of devices for medical and biological applications, in particular for the diagnostic radiology of soft tissues. For these applications, to ensure a high detection efficiency is of crucial importance. This leads to the use of “on purpose” geometrical arrangements and technological solutions for the detector, as well as the use of specifically designed read-out electronics. In this paper we present results and images obtained with silicon microstrip detectors in a “pixel-like” geometry, with the X-ray beam impinging parallel to the strips. An efficiency close to 80% has been obtained for photons of energies around 20 keV. The ongoing developments, concerning the realisation of a dedicated silicon detector for digital radiology at the SYRMEP (SYnchrotron Radiation for MEdical Physics) beam line of the ELETTRA synchrotron radiation facility, are described.

The SYRMEP collaboration is developing a digital mammography project using a synchrotron radiation monochromatic X-ray beam and a silicon pixel detector. The combination of a monochromatic laminar beam with a high efficiency laminar detector, capable of single-photon counting, allows one to minimize the radiation dose delivered to the sample, while maximizing contrast resolution and dynamic range. The SYRMEP detector is a silicon microstrip device used in an innovative configuration in which radiation impinges on the side rather than on the surface of the chip and is therefore totally absorbed within the detector active volume. The high contrast resolution and spatial resolution (

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., Replaced some paragraphs in text and some pictures

A silicon-tungsten sampling imaging calorimeter has been designed and built for thePAMELA satellite-borne experiment. The main physics goals of the experiment are themeasurement of the flux of anti ...

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.

The PAMELA experiment is a multi-purpose apparatus built around a permanent magnet spectrometer, with the main goal of studying in detail the antiparticle component of cosmic rays. The apparatus will be carried in space by means of a Russian satellite, due to launch in 2005, for a three year-long mission. The characteristics of the detectors composing the instrument, alongside the long lifetime of the mission and the orbital characteristics of the satellite, will allow to address several items of cosmic-ray physics. In this paper, we will focus on the solar and heliospheric observation capabilities of PAMELA.

The PHENIX detector at RHIC has been designed to study hadronic and leptonic signatures of the Quark Gluon Plasma in heavy ion collisions and spin dependent structure functions in polarized proton collisions. The baseline detector measures muons in two muon spectrometers located forward and backward of mid-rapidity, and measures hadrons, electrons, and photons in two central spectrometer arms, each of which covers 90/spl deg/ in azimuth and 0.35 units of rapidity. Further progress requires extending rapidity coverage for hadronic and electromagnetic signatures by upgrading the functionality of the PHENIX muon spectrometers to include photon and jet measurement capabilities. Tungsten calorimeters with silicon pixel readout and fine transverse and longitudinal segmentation are proposed to attain this goal. The use of such a design provides the highest density and finest granularity possible in a calorimeter.

PAMELA is a satellite-borne experiment that will study the antiproton and positron fluxes in cosmic rays in a wide range of energy (from 80 MeV up to 190 GeV for antiprotons and from 50 MeV up to 270 GeV for positrons) and with high statistics, and that will measure the antihelium/helium ratio with a sensitivity of the order of 10/sup -8/. The detector will fly on-board a polar orbiting Resurs DK1 satellite, which will be launched into space by a Soyuz rocket in 2004 from Baikonur cosmodrome in Kazakhstan, for a 3-year-long mission. Particle identification and energy measurements are performed in the PAMELA apparatus using the following subdetectors: a magnetic spectrometer made up of a permanent magnet equipped with double-sided microstrip silicon detectors, an electromagnetic imaging calorimeter composed of layers of tungsten absorber and silicon detectors planes, a transition radiation detector made of straw tubes interleaved with carbon fiber radiators, a plastic scintillator time-of-flight and trigger system, a set of anticounter plastic scintillator detectors, and a neutron detector. The features of the detectors and the main results obtained in beam test sessions are presented.

We present in this paper a status report of the space experiment PAMELA. PAMELA is a satellite-borne experiment which primarily aims to measure the antiproton and positron spectra in the cosmic rad ...

The measurement of the atmospheric muon spectrum is currently of great interest because of the study of atmospheric neutrinos and the claim of neutrino oscillations made in 1998 by the Super-Kamiokande Collaboration. A measurement of the muon flux is an indirect measure of the neutrino flux. Therefore, it can be used to improve the calculation of the atmospheric neutrino flux, which in turn can be compared with the observed neutrino rates in underground detectors. This article reports a new measurement of the m 1 and m 2 spectra at several atmospheric depths in the momentum ranges 0.3‐20 GeV/c and 0.3‐40 GeV/c, respectively. The data were collected by the balloon-borne experiment CAPRICE98 during the ascent of the payload on 28 May 1998 from Fort Sumner, N. M. The experiment used the NMSU-WIZARD/CAPRICE 98 balloon-borne magnet spectrometer equipped with a gas ring imaging Cherenkov detector and a silicon-tungsten calorimeter.

[1] In this paper we report on the energy spectra and abundance ratios of hydrogen and helium isotopes of albedo origin, measured by the instruments NINA and NINA-2 in near-equatorial regions. The instrument NINA flew on board the satellite Resurs-01-N4 between 1998 and 1999, at a 830 km average altitude. The NINA-2 apparatus, on board the satellite MITA, was put into orbit in July 2000 at an altitude of about 450 km. NINA and NINA-2 measurements revealed that 2H, 3H, 3He, and 4He are a significant portion of the secondary flux above the atmosphere. The energy spectra of hydrogen isotopes are practically flat across the energy range of 10–40 MeV/n, while the spectra of helium isotopes can be fitted by a power law of spectral indexes γ = 0.8 and γ = 1.5 for 3He and 4He, respectively.

A new measurement of the primary cosmic-ray proton and helium fluxes from 3 to 350 GeV was carried out by the balloon-borne CAPRICE experiment in 1998. This experimental setup combines different detector techniques and has excellent particle discrimination capabilities allowing clear particle identification. Our experiment has the capability to determine accurately detector selection efficiencies and systematic errors associated with them. Furthermore, it can check for the first time the energy determined by the magnet spectrometer by using the Cherenkov angle measured by the RICH detector well above 20 GeV/n. The analysis of the primary proton and helium components is described here and the results are compared with other recent measurements using other magnet spectrometers. The observed energy spectra at the top of the atmosphere can be represented by (1.27+-0.09)x10^4 E^(-2.75+-0.02) particles (m^2 GeV sr s)^-1, where E is the kinetic energy, for protons between 20 and 350 GeV and (4.8+-0.8)x10^2 E^(-2.67+-0.06) particles (m^2 GeV nucleon^-1 sr s)^-1, where E is the kinetic energy per nucleon, for helium nuclei between 15 and 150 GeV nucleon^-1., To be published on Astroparticle Physics (44 pages, 13 figures, 5 tables)

The SYRMEP/FRONTRAD experiment is performing a R&D program in order to assess the performances of a scanning X-ray detector operating at the ELETTRA Synchrotron light source, in an energy range optimized for mammographic imaging. The detector itself consists of a stack of silicon detectors positioned edge-on with respect to the X-ray beam direction. The data acquisition system must perform several tasks: from the control of the motors during the scanning procedure, to the collection of the data that are recorded on CAMAC modules and refer to the slots of the image while it is forming. The system has to process the data during the scan and to store them on a local disk. In addition, the environmental conditions (global dose measured by an ionization chamber, temperature, dark current of the detector and status of the electronics power supplies) have to be monitored and the proper action taken. We have implemented a multiprocessing system using TCP/IP and RPC to manage the tasks. The overall control is done by a GUI built using the Tcl/Tk package.

Silicon drift detectors with an active area of 7.0 × 7.5 cm 2 will equip the two middle layers of the Inner Tracking System of the ALICE experiment. The performance of several prototypes was studied during beam tests carried out at the CERN SPS facility. The results of the beam test data analysis are discussed in this paper.

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 equipemet 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 energy (190 GeV for p and 270GeV for e~) and to search antinuclei, up to 30 GeV/n, with a sensitivity of 10-7 in the He/He ratio. 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 energy (190 GeV for p and 270GeV for e-) and to search antinuclei, up to 30GeV/n, with a sensitivity of 10 in the He/He ratio. The PAMELA telescope consists of: a magnetic spectrometer made up of a permanent magnet system equipped with double sided microstrip silicon detectors; a transition radiation detector made up of active layers of proportional straw tubes interleaved with carbon fibre radiators; and a silicon-tungsten imaging calorimeter made up of layers of tungsten absorbers and silicon detector planes. A time-of-flight system and anti- coincidence counters complete the PAMELA equipment. In the past years. tests have been done on each subdetector of PAMELA; the main results are presented and their implications on the anti-particles identification capability in cosmic rays are discussed here.

The CAPRICE98 balloon-borne instrument was flown on 28–29 May 1998 from Fort Sumner (New Mexico, USA). The detector configuration included the NMSU-WiZard/CAPRICE superconducting-magnet spectrometer equipped with a gas RICH, a silicon-tungsten calorimeter and a time-of-flight system. By combining the information from the spectrometer and the RICH, which was used as a threshold device, it was possible to separate 2 H from 1 H in the kinetic energy range from 12 to 22 GeV/n. In order to estimate the proton background and the deuteron selection efficiency, an empirical model for the response of the instrument, based on the data collected in this experiment, was developed. The analysis procedure is described in this paper and the results on the absolute flux of 2 H and 2 H/He ratio are presented. These data on 2 H abundance represent the only measurements above 10 GeV/n.