Micro-pattern gaseous detectors in high-energy and astroparticle physics

Introduced in the late 70s of the last century, a new generation of position-sensitive sensors named micro-pattern gaseous detectors (MPGDs) allows to detect and localize ionizing radiation with sub-mm accuracy and high-rate capability. Performing and reliable, MPGDs are gradually replacing detection systems based on multiwire proportional chambers, and find applications in particle physics, astrophysics, plasma diagnostics and other fields.

Исследование радиационной эрозии в газоразрядном детекторе с помощью атомно-силовой микроскопии

Using Atomic Force Microscopy Methods, we studied the samples of the cathodes of multiwire proportional chambers after long-term irradiation with a beta-source 90Sr at the longevity test. The changes in the morphology of the copper foil surface at the cathode of the detector as a result of the influence of the electron flow are described. It is presented a quantitative assessment and analysis of the evolution of the resulting radiation defects depending on the irradiation conditions. It is shown the similarity of the radiation defects in the laboratory prototypes and in full scale proportional chambers that have been operated at the LHC for almost 10 years.

Tracking system performance of the BM@N experiment

The Baryonic Matter at Nuclotron (BM@N) experiment represents the first phase of the Nuclotron-based Ion Collider Facility (NICA), a mega-science project at the Joint Institute for Nuclear Research. It is a fixed target experiment built for studying nuclear matter in conditions of extreme density and temperature. The tracking system of the BM@N experiment consists of three main detector systems: Multiwire Proportional Chambers situated before the magnet, Gas Electron Multipliers placed inside the magnet and Drift Chambers placed after the magnet. These systems provide the reconstruction of charged particles’ trajectories and their momentum in the magnetic field. This information is further used by Time of Flight detectors for the particle identification procedure. The system’s performance is reviewed and the spatial resolutions along with efficiencies of the detectors are estimated using the data collected in the recent physics runs of the Nuclotron.

Nuclotron Beam Momentum Estimation Using Multiwire Proportional Chambers and Drift Chambers in the BM@N Experiment

The BM@N experiment is considered as the first phase of NICA Mega science project. The energy of the beam will vary from 1 to 6 GeV/u. The beams delivered by Nuclotron will be of different types from protons to Au. The ability to reconstruct the beam momentum with high precision is one way for showing that the tracking detectors are tuned in the right way and the reconstruction procedure performs well. A quick overview of the experimental setup is given in the work along with the description of some of the main tracking detectors. The beam momentum reconstruction procedure is described and results are presented for different values of the beam energy.

Experimental Facility at A2 Collaboration (MAINZ) for Photoproduction reaction

<p>Since 20 years, a very successful experimental program with real photons has been achieved at the Mainz Microtron (MAMI) facility. The A2 Collaboration at MAINZ is a unique place for the experimental facility of photoproduction reaction. The combination of highly sensitive photo spectrometers Crystal Ball and TAPS as forward wall detector along with particle identification detector and Multiwire proportional chambers as inner wall detectors provide the high precision of the measurement. MAMI-C, which consists of there Race Track Microtrons (RTMs) with the Harmonic Double -Sided Microtron (HDSM) is an intense, stable and continuous-wave accelerator to accelerate electron to 1.5 GeV. This electron beam is responsible to produce real photons via bremsstrahlung process at Glasgow Photon Tagger. A major part of the ongoing and future programme at MAMI will exploit polarised nucleon targets.</p><p>Journal of Nepal Physical Society Vol.3(1) 2015: 73-81</p>

Fast High Resolution Position-Sensitive Gaseous Detectors

The present review describes a new coordinate detectors based on gas micro-pattern technology, which are applied in experiments in elementary particle physics and with SR beams. The microstrip gas chambers (MSGC) on substrates with electronic conductivity are presented in the paper. Such detectors are shown to have spatial resolution better than 100 micron and to be able to effectively operate at particle rates up to 106 s-1mm-2, that at least by two orders of magnitude higher than rate capability of multiwire proportional chambers. Essential part of the review is devoted to studies of the cascades of gas electron multipliers (GEM). In particular, the dependence of gas amplification and conditions of a discharge occurrence on the number of GEMs in cascade, on the distribution of potentials between GEMs in cascade and on gas mixture in the presence of hadron flux are discussed. Gas micro-pattern technology is widely used for the development of coordinate detectors. In the present review we describe as an example the detectors with triple GEM cascades for the tagging system of the KEDR experiment at the VEPP-4M collider