The Experts below are selected from a list of 210 Experts worldwide ranked by ideXlab platform
Fabio Sauli - One of the best experts on this subject based on the ideXlab platform.
-
the gas Electron Multiplier gem operating principles and applications
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2016Co-Authors: Fabio SauliAbstract:Introduced by the author in 1997, The Gas Electron Multiplier (GEM) constitutes a powerful addition to the family of fast radiation detectors; originally developed for particle physics experiments, the device and has spawned a large number of developments and applications; a web search yields more than 400 articles on the subject. This note is an attempt to summarize the status of the design, developments and applications of the new detector.
-
Imaging with the gas Electron Multiplier
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2007Co-Authors: Fabio SauliAbstract:The Gas Electron Multiplier (GEM), introduced several years ago, is finding numerous applications thanks to its excellent performances in detecting and localizing ionizing radiation. This note summarizes recent developments of the technology, and presents some examples of applications.
-
Progress with the gas Electron Multiplier
Nuclear Instruments and Methods in Physics Research Section A: Accelerators Spectrometers Detectors and Associated Equipment, 2004Co-Authors: Fabio SauliAbstract:Offering position accuracies of few tens of microns and rate capabilities close to a MHz mm/sup -2/, detectors using the gas Electron Multiplier (GEM) as amplifying element are attractive whenever a precise knowledge of the energy loss topology is required. Moreover, they are robust and easy to manufacture. Cascading two or more GEM foils permits to achieve larger gains and reliable operation in harsh operating conditions. We discuss the operating principles and the major performances of the new devices, particularly in view of their possible use for particle identification in transition radiation and Cherenkov ring imaging detectors. (26 refs)
-
aging measurements with the gas Electron Multiplier gem
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2003Co-Authors: M C Altunbas, Fabio Sauli, S. Kappler, B. Ketzer, L. Ropelewski, Klaus Dehmelt, F SimonAbstract:Abstract Continuing previous aging measurements with detectors based on the Gas Electron Multiplier (GEM), we investigated a 31×31 cm 2 triple-GEM detector, as used in the small area tracking of the COMPASS experiment at CERN. With a detector identical to those installed in the experiment, long-term high-rate exposures to 8.9 keV X-ray radiation were performed to study its aging properties. In standard operation conditions, with Ar/CO2 (70:30) gas filling and operated at an effective gain of 8.5×103, no change in gain and energy resolution is observed after collecting a total charge of 7 mC / mm 2 , corresponding to seven years of normal operation. This observation confirms previous results demonstrating the relative insensitivity of GEM detectors to aging, even when manufactured with common materials.
-
Development and applications of gas Electron Multiplier detectors
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2003Co-Authors: Fabio SauliAbstract:Recent developments of the Gas Electron Multiplier (GEM) are described, as well as its applications as fast, position-sensitive detector in particle physics, medicine, neutron spectrometry and astrophysics.
S H Byun - One of the best experts on this subject based on the ideXlab platform.
-
development of a thick gas Electron Multiplier based beta ray detector
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2020Co-Authors: M R Bernacci, S H ByunAbstract:Abstract A new beta-ray detector using Thick Gas Electron Multiplier (THGEM) technology is presented. Traditional proportional counters have been considered the standard for many decades for radiation contamination monitoring. However, it has always been challenging to detect low energy beta-emitters like 3H and 14C. In order to extend the low energy cutoff of these beta particles, it is important to keep the Electron multiplication gain as high as possible. To accomplish this goal, we have developed a new gaseous beta-ray detector using THGEMs. Founded on previous THGEM avalanche simulations [1] and predecessor detectors, a prototype THGEM beta-ray detector was designed and fabricated. Its signal performance, effective gain and gain stability were comprehensively studied for single and double-THGEM configurations using an alpha source. The response of the detector to beta-rays was measured for various operating conditions and compared with MCNP6 Monte Carlo simulations.
-
development of a thick gas Electron Multiplier for microdosimetry
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2011Co-Authors: G M Orchard, K Chin, W V Prestwich, A J Waker, S H ByunAbstract:Abstract A new tissue-equivalent proportional counter based on a thick gas Electron Multiplier (THGEM) was developed and tested for microdosimetry. A systematic test was conducted at the McMaster Accelerator Laboratory to investigate the overall performance of the prototype detector. A mixed neutron–gamma-ray radiation field was generated using the 7 Li(p,n) reaction. The detector was operated at low voltage initially to test the stability and then the relative multiplication gain was measured as a function of the operating high voltage. A drift potential of 100 V and a THGEM bias of 727 V generated a multiplication gain sufficient for the detection of both neutron and gamma-ray radiation. A consistent microdosimetric pattern was observed between the THGEM detector and standard TEPC for microdosimetry.
J.f.c.a. Veloso - One of the best experts on this subject based on the ideXlab platform.
-
the thick cobra a new gaseous Electron Multiplier for radiation detectors
Journal of Instrumentation, 2010Co-Authors: F. D. Amaro, A. Breskin, J.f.c.a. Veloso, Celso Augusto Guimaraes Santos, R Chechik, J Dos M F SantosAbstract:The operation principle and preliminary results of a novel gas-avalanche patterned hole Electron Multiplier, the Thick-COBRA (THCOBRA), are presented. This micro-hole structure is derived from the THGEM and MHSP. Sub-millimeter diameter holes are mechanically drilled in a thin G10 plate, Cu-clad on both faces; on one of the faces the Cu is etched to produce additional anode strips winding between circular cathode strips. Primary avalanches occurring within the holes are followed by additional ones at the anode-strips vicinity. Gains in excess of 5*104were reached with 22.1 keV x-rays in Ar, Ne and Ar-10%CH4, with 12.2 % FWHM energy resolution in Ar-10%CH4. Higher gains were measured with single photoElectrons. This robust Multiplier may have numerous potential applications.
-
short induction gap gas Electron Multiplier gem for x ray spectroscopy
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2007Co-Authors: J A Mir, J.f.c.a. Veloso, R Stephenson, N J Rhodes, E M Schooneveld, J Dos M F SantosAbstract:Abstract Experimental work was carried out to evaluate the performance of a Gas Electron Multiplier (GEM) operated with a micromesh readout plane that enabled the induction gap to be set at 50 μm. We measured the essential operational parameters of this system using Ar(75%)-isobutane (25%) as the counter gas mixture. The measurements included the effective gain, effective gain stability, and the X-ray energy resolution using a 5.89 keV X-ray source. These studies demonstrated several advantages of the current system when compared with the standard operation, such as lower operational voltages, higher effective gains and improved effective gain stability.
-
Progress in MHSP Electron Multiplier operation
IEEE Transactions on Nuclear Science, 2004Co-Authors: J.m. Maia, D. Mörmann, A. Breskin, Rachel Chechik, J.f.c.a. Veloso, J.m.f. Dos SantosAbstract:The Micro-Hole & Strip-Plate gas Electron Multiplier (MHSP) was studied as a stand-alone device or in combination with a cascade of Gas Electron Multipliers (GEMs), for x-ray and UV-photon detection. An MHSP operating in Ar/5%Xe yielded gains above 10/sup 4/ and energy resolutions of about 14% FWHM for 5.9-keV x-rays. Gains as high as 10/sup 7/ were reached in a 3-GEM/MHSP gaseous photoMultiplier operating in an Ar/5%CH/sub 4/; the ion-backflow fraction to the top of the first GEM could be reduced down to /spl sim/2% 2D-imaging performed using signals induced by avalanche ions on a Wedge-and-Strip readout cathode, placed at close proximity of the anode strips yielded position resolutions of the order of 200 to 250 /spl mu/m FWHM for 5.9-keV x-rays.
M Cortesi - One of the best experts on this subject based on the ideXlab platform.
-
multi layer thick gas Electron Multiplier m thgem a new mpgd structure for high gain operation at low pressure
Review of Scientific Instruments, 2017Co-Authors: M Cortesi, S Rost, W Mittig, Y Ayyadlimonge, Daniel Bazin, J Yurkon, A StolzAbstract:The operating principle and performances of the Multi-layer Thick Gaseous Electron Multiplier (M-THGEM) are presented. The M-THGEM is a novel hole-type gaseous Electron Multiplier produced by multi-layer printed circuit board technology; it consists of a densely perforated assembly of multiple insulating substrate sheets (e.g., FR-4), sandwiched between thin metallic-electrode layers. The Electron avalanche processes occur along the successive multiplication stages within the M-THGEM holes, under the action of strong dipole fields resulting from the application of suitable potential differences between the electrodes. The present work focuses on the investigation of two different geometries: a two-layer M-THGEM (either as single or double-cascade detector) and a single three-layer M-THGEM element, tested in various low-pressure He-based gas mixtures. The intrinsically robust confinement of the avalanche volume within the M-THGEM holes provides an efficient reduction of the photon-induced secondary effects, resulting in a high-gain operation over a broad pressure range, even in pure elemental gas. The operational principle, main properties (maximum achievable gain, long-term stability, energy resolution, etc.) under different irradiation conditions, as well as capabilities and potential applications are presented and discussed.
-
multi layer thick gas Electron Multiplier m thgem a new mpdg structure for high gain operation at low pressure
arXiv: Instrumentation and Detectors, 2016Co-Authors: M Cortesi, S Rost, W Mittig, Daniel Bazin, J Yurkon, Ayyad Y Limonge, A StolzAbstract:The operating principle and performances of the Multi-layer Thick Gaseous Electron Multiplier (M-THGEM) is presented. The M-THGEM is a novel hole-type gaseous Electron Multiplier produced by multi-layer printed circuit board technology; it consists of a densely perforated assembly of multiple insulating substrate sheets (e.g., FR-4), sandwiched between thin metallic-electrode layers. The Electron avalanche processes occur along the successive multiplication stages within the M-THGEM holes, under the action of strong dipole fields resulting from the application of suitable potential differences between the electrodes. The present work focuses on investigation of two different geometries: a two-layer M-THGEM (either as single or double-cascade detector) and a single three-layer M-THGEM element, tested in various low-pressure He-based gas mixtures. The intrinsically robust confinement of the avalanche volume within the M-THGEM holes provides an efficient suppression of the photon-induced secondary effects, resulting in a high-gain operation over a broad pressure range, even in pure noble gas. The operational principle, main properties (maximum achievable gain, long-term stability, energy resolution, etc.) under different irradiation conditions, as well as capabilities and potential applications are discussed.
-
development of a cold neutron imaging detector based on thick gaseous Electron Multiplier
Review of Scientific Instruments, 2013Co-Authors: M Cortesi, Robert Zboray, A Kaestner, Horstmichael PrasserAbstract:We present the results of our recent studies on a cold-neutron imaging detector prototype based on THick Gaseous Electron Multiplier (THGEM). The detector consists of a thin Boron layer, for neutron-to-charged particle conversion, coupled to two THGEM electrodes in cascade for charge amplification and a position-sensitive charge-readout anode. The detector operates in Ne/(5%)CF4, at atmospheric pressure, in a stable condition at a gain of around 104. Due to the geometrical structure of the detector elements (THGEM geometry and charge read-out anode), the image of detector active area shows a large inhomogeneity, corrected using a dedicated flat-filed correction algorithm. The prototype provides a detection efficiency of 5% and an effective spatial resolution of the order of 1.3 mm.
C W E Van Eijk - One of the best experts on this subject based on the ideXlab platform.
-
design of a new tissue equivalent proportional counter based on a gas Electron Multiplier
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2003Co-Authors: M Farahmand, A J J Bos, J Huizenga, L De Nardo, C W E Van EijkAbstract:By employing a Gas Electron Multiplier a new type of mini multi-element Tissue-Equivalent Proportional Counter (TEPC) has been designed and constructed. In this paper, we describe the design of this novel counter. The first pulse height measurements with this counter for both methane- and propane-based Tissue Equivalent gases are presented. These results show promising properties for application of this novel type TEPC in microdosimetric measurements.
-
gas Electron Multiplier gem operation with tissue equivalent gases at various pressures
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2003Co-Authors: M Farahmand, A J J Bos, C W E Van EijkAbstract:Abstract We have studied the operation of two different Gas Electron Multiplier (GEM) structures in both methane and propane based Tissue-Equivalent (TE) gases at different pressures varying from 0.1 to 1 atm. This work was motivated to explore the possibility of using a GEM for a new type of Tissue Equivalent Proportional Counter. In methane based TE gas, a maximum safe GEM gain of 1.5×10 3 has been reached while in propane based TE gas this is 6×10 3 . These maxima have been reached at different gas pressures depending on GEM structure and TE gas. Furthermore, we observed a decrease of the GEM gain in time before it becomes stable. Charge up/polarisation effects can explain this.