This paper reports about the first Micromegas-based telescope built for applications in muon tomography. The telescope consists of four, 50×50cm2 resistive multiplexed Micromegas with a 2D layout and ...a self-triggering electronics based on the Dream chip. Thanks to the multiplexing, the four detectors were readout with a single Front-End Unit. The high voltages were provided by a dedicated card using low consumption CAEN miniaturized modules. A nano-PC (Hummingboard) ensured the HV control and monitoring coupled with a temperature feedback as well as the data acquisition and storage. The overall consumption of the instrument yielded 30W only, i.e. the equivalent of a standard bulb. The telescope was operated outside during 3.5months to image the water tower of the CEA-Saclay research center, including a 1.5-month campaign with solar panels. The development of autonomous, low consumption muon telescopes with unprecedented accuracy opens new applications in imaging as well as in the field of muon metrology.
Why do we flush gas in gaseous detectors? Procureur, S.; Attié, D.; Bouteille, S. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
03/2020, Letnik:
955
Journal Article
Recenzirano
Odprti dostop
The effects and the origin of the gas degradation in a gaseous detector-based tracker are investigated. The study focused on the so-called T2K gas, which turned out to be highly sensitive to ...pollutants. In particular the H2O and O2 concentrations were monitored online in different conditions to establish their influence on the gain of the detectors. This pollution was first mitigated by a recirculating and accelerating gas system with the use of a turbine and different absorbers. Further measurements revealed that this pollution originates from a continuous permeation process through the different materials of the gas circuit. In particular, polyurethane-based gas pipes or polyester materials largely increase the level of humidity. As a direct consequence of this work, the gas autonomy of the muon telescopes currently deployed inside the Khufu’s pyramid have been dramatically improved.
A new radial time projection chamber based on Gas Electron Multiplier amplification layers was developed for the BONuS12 experiment in Hall B at Jefferson Lab. This device represents a significant ...evolutionary development over similar devices constructed for previous experiments, including cylindrical amplification layers constructed from single continuous GEM foils with less than 1% dead area. Particular attention had been paid to producing excellent geometric uniformity of all electrodes, including the very thin metalized polyester film of the cylindrical cathode. This manuscript describes the design, construction, and performance of this new detector.
Due to their simplicity and versatility of design, straight strip or rectangular pad anode structures are frequently used with micropattern gas detectors (MPGDs) to reconstruct high-precision space ...points for various tracking applications. The particle impact point is typically determined by interpolating the charge collected by several neighboring strips. However, to effectively extract the inherent positional information, the lateral spacing of the straight strips must be comparable to or preferably smaller than the full extent of the incident charge cloud. In contrast, highly interleaved anode patterns, such as zigzags, can adequately sample the incident charge with a pitch appreciably larger than the charge cloud. This has the considerable advantage of providing the same performance while requiring far fewer instrumented channels. Additionally, the geometric parameters defining such zigzag structures may be tuned to provide a near-uniform detector response along and perpendicular to the sensitive coordinate, without the need for so-called "pad response functions," while simultaneously maintaining excellent position resolution. We have measured the position resolution of a variety of zigzag-shaped anode patterns optimized for various MPGDs, including gas electron multiplyer (GEM), Micromegas, and micro-resistive-well (<inline-formula> <tex-math notation="LaTeX">\mu </tex-math></inline-formula>RWELL) and compared this performance with the same detectors equipped with straight strips of varying pitch. We report on the performance results of each readout structure, evaluated under identical conditions in a test beam.
We have developed highly interleaved zigzag-shaped electrodes for collecting charge on the readout plane of various micropattern gaseous detectors (MPGDs), including gas electron multiplier (GEM) and ...micromega detectors. An optimized zigzag pad (or strip) anode can greatly enhance charge sharing among neighboring pads compared to traditional straight strip or rectangular pad designs and as a result can deliver excellent position resolution with minimal channel count, while exhibiting a virtually uniform response across the detector. We have systematically studied the effects of varying the parameters that define the zigzag geometry using simulations and have measured several printed circuit boards (PCBs) comprising a range of zigzag designs. Recently, we have employed laser ablation to generate zigzag patterns with pad-to-pad gaps smaller than 1 mil (or 25 <inline-formula> <tex-math notation="LaTeX">\mu \text{m} </tex-math></inline-formula>). Reducing the gap well below the 3-mil limit imposed by traditional chemical etching has allowed the production of zigzag electrodes with unprecedentedly small feature sizes. In turn, laser-etched zigzag PCBs were shown to exhibit markedly improved performance over earlier generation PCBs, with position resolutions below 50 <inline-formula> <tex-math notation="LaTeX">\mu \text{m} </tex-math></inline-formula> for a 2-mm pitch. This article will explore in detail the dependence of the position resolution on the structural parameters of a zigzag-shaped anode, specifically for the case of a quadruple GEM detector.
Abstract
A muon metrology experiment is presented: two distant muon detection systems are used in coincidence to detect these particles originating from primary cosmic rays. The excellent spatial ...resolution of the Micromegas detectors allows for a precise relative positioning of the two instruments. The current setup can be used to monitor mid- or long-term deformations of a structure down to sub-millimeter resolution. It could also be employed to roughly position a distant structure with single muon detection, a typical example being an underground cavity whose position with respect to the surface is poorly known.
Potential applications of muon tomography, or muography, as non-invasive scanning method have increased in the last years together with the performance of the particle detectors used for muon ...detection, known as muon telescopes. A new concept muon telescope is presented, which could enlarge even more the range of application of this technique. It is based on a compact TPC equipped with a 2D pixelized Micromegas detector with multiplexed readout. This detector will overcome some of the constraints of the instruments currently used, as they limited acceptance, while keeping other features required for muography as stability, robustness or portability. Moreover, it will be capable to reconstruct the 3D direction of the incident muons with a single instrument. With its design and features, this kind of detectors can be fitted at boreholes from where they can scan the surroundings, being an interesting technique for mining exploration, geotechnics or monitoring of dykes or bridges which has arouse the interest of industry. In a further phase it is expected to develop a network of these detectors which will allow the 3D reconstruction of the studied object by the combination of the images registered by each of the telescopes. Main features and first tests and results of this new instrument will be presented together with some studies, performed by Monte Carlo simulations, of the capabilities of this muon telescope and the analysis principle.
Operation of a resistive Micromegas in air Procureur, S.; Attié, D.; Aune, S. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
10/2012, Letnik:
688
Journal Article
Recenzirano
The recent developments on resistive Micromegas have enhanced the performance of this detector, and in particular have offered the possibility to reach higher amplification gains in stable operation. ...In this paper, the detection capabilities of a resistive Micromegas in air have been investigated. A clear Fe55 spectrum has been obtained, as well as MIP signals using cosmic rays. In the latter case, the detection efficiency reaches 42%, and could probably be further improved. The stable operation of a gaseous detector in air, i.e. without bottles, pipes or safety systems, can lead to many new applications or simplifications of existing setups.
Discharge studies in Micromegas detectors in low energy hadron beams Charles, G.; Anfreville, M.; Aune, S. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
08/2011, Letnik:
648, Številka:
1
Journal Article
Recenzirano
We present measurements of discharge rates in various Micromegas detectors in low energy hadron beams for applications foreseen at the future experiments CLAS12 at JLab and MINOS at GSI. The tests ...were performed in the T11 beam line of the CERN/PS using hadron beams with momentum between 0.2 and 3GeV/c. The discharge probability decreases smoothly below 1GeV/c, except at some specific energies where narrow peaks are observed. The position of the peaks corresponds to the stop point of protons and heavier particles, predicted by the Geant4 simulation. Discharge rates were also measured using Micromegas prototypes equipped with a GEM foil as foreseen for the COMPASS experiment at CERN.
This report describes the physics case, the resulting detector requirements, and the evolving detector concepts for the experimental program at the Electron-Ion Collider (EIC). The EIC will be a ...powerful new high-luminosity facility in the United States with the capability to collide high-energy electron beams with high-energy proton and ion beams, providing access to those regions in the nucleon and nuclei where their structure is dominated by gluons. Moreover, polarized beams in the EIC will give unprecedented access to the spatial and spin structure of the proton, neutron, and light ions. The studies leading to this document were commissioned and organized by the EIC User Group with the objective of advancing the state and detail of the physics program and developing detector concepts that meet the emerging requirements in preparation for the realization of the EIC. The effort aims to provide the basis for further development of concepts for experimental equipment best suited for the science needs, including the importance of two complementary detectors and interaction regions. This report consists of three volumes. Volume I is an executive summary of our findings and developed concepts. In Volume II we describe studies of a wide range of physics measurements and the emerging requirements on detector acceptance and performance. Volume III discusses general-purpose detector concepts and the underlying technologies to meet the physics requirements. These considerations will form the basis for a world-class experimental program that aims to increase our understanding of the fundamental structure of all visible matter
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