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The upgrade of the ATLAS detector at the Large Hadron Collider (LHC) at CERN calls for a new generation of muon detectors capable of operating in a flux of collision and background particles approximately ten times larger compared to today's conditions. We report here on the Muon ATLAS MicroMegas Activity (MAMMA) R&D project aimed at the construction of large-area spark-resistant muon chambers using the micromegas technology.

In 2000, the requirements for a large TPC for experiments at a new linear collider were formulated. Both the GEM and Micromegas gas amplification systems had matured, such that they could be practically applied. With the Medipix chip, a pixel-segmented anode readout became possible, offering an unprecedented level of granularity and sensitivity. The single electron sensitive device is a digital detector capable to record and transfer all information of the primary ionization, provided that it can be made discharge proof.

Micromegas-based detectors are used in a wide variety of neutron experiments. Their fast response meets the needs of time-of-flight facilities in terms of time resolution. The possibility of constructing low mass Micromegas detectors makes them appropriate for beam imaging and monitoring without affecting the beam quality or inducing background in parallel measurements. The good particle discrimination capability allows using Micromegas for neutron induced fission and (n, α) cross-section measurements. Their high radiation resistance make them suitable for working as flux monitors in the core of fission nuclear reactors as well as in the proximity of fusion chambers. New studies underlined the possibility of performing neutron computed tomography (CT) with Micromegas as neutron detectors, but also of exploiting its performances in experiments of fundamental nuclear physics.

Modern experiments in hadronic physics require excellent detection and tracking capabilities in very high flux environment. Probing the quark and gluon content of the nucleon indeed necessitates semi-inclusive or exclusive reactions with very small cross-sections. Micromegas detectors have therefore been rapidly identified as natural candidates to equip the hottest region of the COMPASS spectrometer at CERN. Benefitting from several years of smooth operation at COMPASS, the Micromegas have been proposed to equip the future central tracker of the CLAS12 experiment at the Jefferson Laboratory. This project triggered an important R&D on the bulk and resistive technologies and inspired several projects involving cylindrical trackers. This paper focuses on the design and performance of the COMPASS and CLAS12 Micromegas, and reviews the R&D made on the discharge reduction in large hadron fluxes.

The Micromegas detectors have been gaining importance as reliable options in their implementation to Time Projection Chambers (TPCs) in experiments searching for Rare Events mainly due to their demonstrated good performance regarding low background levels, energy and time resolution, gain and stability of operation. In the present paper, we will briefly review the latest developments carried out within the T-REX project of detector R&D, and the performance achieved in the context of several experiments: the CAST solar axion search experiment, the NEXT experiment of double beta decay and the MIMAC dark matter directional search.

The upcoming luminosity upgrade of the LHC will impose new requirements for the detector installations. To perform under these conditions the Micromegas (MM) technology was selected to be adopted in the New Small Wheel (NSW) upgrade, dedicated to precision tracking. A large surface of the forward regions of the Muon Spectrometer will be equipped with 8 layers of MM modules forming a total active area of 1200 m². The NSW is planned to be installed in the forward region of $1.3<\left|\eta \right|<2.7$ of ATLAS. This new system will have to operate in a high background radiation region, while reconstructing muon tracks as well as furnishing information for the Level-1 trigger. The project requires fully efficient MM chambers with spatial resolution down to 100 $\mu$m, a rate capability up to about 15 kHz/cm² and operation in a moderate (highly inhomogeneous) magnetic field up to $B=0.3$T. The required tracking is linked to the intrinsic spatial resolution in combination with the demanding mechanical accuracy. An overview of the design, construction and QA/QC procedures followed at the Aristotle University of Thessaloniki for the Micromegas LM2 Drift panels production will be presented.

Micropattern detectors (MPD) and in particular MICROMEGAS are being developed very actively in recent years. While increasingly used now in high energy physics experiments, their application to rare event searches is relatively more recent. In this talk the status of three initiatives in this respect are presented: MICROMEGAS for axion searches in the CAST experiment at CERN, the use of MICROMEGAS technology to measure the recoil direction in WIMP searches, and the development of the spherical TPC concept with applications in low energy neutrino detection.

The Time Projection Chamber (TPC) for the International Linear Collider will need to measure about 200 track points with a spatial resolution close to 100 μm. A Micro Pattern Gas Detector (MPGD) readout TPC could achieve the desired resolution with existing techniques using sub-millimeter pad width at the expense of a large increase in the detector cost and complexity. A new MPGD readout concept of charge dispersion developed in Canada has been recently applied to small prototypes MPGD-TPC. Using cosmic-ray tracks, it demonstrated the feasibility of achieving good resolution with pads similar in width to the ones used for the proportional wire TPC. The charge dispersion technique was used with GEM and micromegas and results on resolution studies are presented. The TPC resolution with GEM and micromegas readout are compared to the earlier results without charge dispersion. First results of performance with charge dispersion in a magnetic field of strength comparable to that for the ILC detector are presented. An unprecedented 50 μm resolution has been achieved, which is an important step toward demonstrating the feasibility of meeting the challenging ILC TPC goal.

EXO-200 (Enriched Xenon Observatory - 200kg) is an underground double-beta decay experiment that uses 200kg of Xenon isotopically enriched to 80% in Xenon-136. The Xenon is contained in an ultra-low background TPC where there is simultaneous collection of scintillation light (using Large Area Avalanche Photodiodes (LAAPD's)) and ionization charge in order to significantly enhance the energy resolution. EXO-200 should measure the, as yet unobserved, two neutrino double-beta decay mode as well as achieve competitive sensitivity for the neutrinoless double-beta decay mode of Xenon-136. EXO-200 is currently undergoing final construction and commissioning. R&D is being conducted towards the construction of a ton-class detector. A high-resolution micropattern (MicroMegas) readout system is being studied in Bern, Switzerland. The scheme offers full tracking capabilities and 3D event reconstruction for possible application in a future gas-phase EXO detector.

RD51 collaboration was founded in April 2008 to coordinate and facilitate the development of micropattern gaseous detectors (MPGDs). 59 institutes from 20 countries bundled their effort, experience and resources to develop these emerging micropattern technologies. MPGDs are already employed in several nuclear and high-energy physics experiments, medical imaging instruments and photodetection applications; many further applications are foreseen. They outperform traditional wire chambers in terms of rate capability, time and position resolution, granularity, stability and radiation hardness. One of the most challenging goals is the possibility to realize large area MPGDs (in particular GEMs, ThickGEMs and Micromegas) for future experiments and possible LHC upgrades. In order to achieve this goal new MPGDs production techniques are being studied.

The International Linear Collider (ILC) will require a large volume Time Projection Chamber (TPC) with transverse space-point resolution of 100 μm for all tracks over the full 2 m drift region. It has been shown that a conventional readout GEM TPC can achieve this resolution using 1 mm or narrower readout pads, at the expense of detector cost and complexity. A new readout technique using the principle of charge dispersion has demonstrated that the transverse resolution goal can be achieved using 2-3 mm wide pads in both small (COSMo) and large (LCTPC) prototype detectors. However, the effect of this new technique on the time resolution was not a part of these studies. Here we present re-analyses of a 4 GeV π⁺ beam test at KEK and a high magnetic field cosmic ray test at DESY carried out with the COSMoTPC with charge dispersion. We find the time resolution comparable to conventional MPGD and wire/pad readout TPCs, and consistent with the ILC z-resolution requirements of 500 and 1400 μm at zero and 2 m drift distances, respectively.

In-flight gamma spectroscopy of rare isotopes at relativistic energies, from fifty to several hundreds of MeV/nucleon, is one of the most efficient tools to investigate shell effects in exotic nuclei.We propose a new method to increase the sensitivity of prompt-gamma spectroscopy by more than one order of magnitude compared to existing setups, leading to a significant step forward. The intended program is based on proton-induced knockout reactions such as (p, 2p). Experiments should take advantage of the most exotic neutron-rich beams produced at the RIBF¹ in RIKEN and the upcoming european FAIR facility. MINOS has been funded by the European Research Council for the 2010-2015 period.

The International Linear Collider (ILC) will require a large volume Time Projection Chamber (TPC) with transverse space-point resolution of 100 μm for all tracks over the full 2 m drift region. The LC-TPC collaboration tested various detector modules at the EUDET facility at DESY. Preliminary results of the 2012-2013 test beam campaign are reported here.