45 research outputs found
New pixelized Micromegas detector with low discharge rate for the COMPASS experiment
New Micromegas (Micro-mesh gaseous detectors) are being developed in view of
the future physics projects planned by the COMPASS collaboration at CERN.
Several major upgrades compared to present detectors are being studied:
detectors standing five times higher luminosity with hadron beams, detection of
beam particles (flux up to a few hundred of kHz/mm^{2}, 10 times larger than
for the present Micromegas detectors) with pixelized read-out in the central
part, light and integrated electronics, and improved robustness. Two solutions
of reduction of discharge impact have been studied, with Micromegas detectors
using resistive layers and using an additional GEM foil. Performance of such
detectors has also been measured. A large size prototypes with nominal active
area and pixelized read-out has been produced and installed at COMPASS in 2010.
In 2011 prototypes featuring an additional GEM foil, as well as an resistive
prototype, are installed at COMPASS and preliminary results from those
detectors presented very good performance. We present here the project and
report on its status, in particular the performance of large size prototypes
with an additional GEM foil.Comment: 11 pages, 5 figures, proceedings to the Micro-Pattern Gaseous
Detectors conference (MPGD2011), 29-31 August 2011, Kobe, Japa
X-ray imaging with Micromegas detectors with optical readout
In the last years, optical readout of Micromegas gaseous detectors has been
achieved by implementing a Micromegas detector on a glass anode coupled to a
CMOS camera. Effective X-ray radiography was demonstrated using integrated
imaging approach. High granularity values have been reached for low-energy
X-rays from radioactive sources and X-ray generators.
Detector characterization with X-ray radiography has led to two applications:
neutron imaging for non-destructive examination of highly gamma-ray emitting
objects and beta imaging for the single cell activity tagging in the field of
oncology drug studies.
First measurements investigating the achievable spatial resolution of the
glass Micromegas detector at the SOLEIL synchrotron facility with a
high-intensity and flat irradiation field will be shown in this article.Comment: 6 pages, 4 figures, 7th International Conference on Micro Pattern
Gaseous Detectors, 11-16 December 20223, Weizmann Institute of Science,
Rehovot, Israe
Development of a novel segmented mesh MicroMegas detector for neutron beam profiling
A novel MicroMegas detector based on microbulk technology with an embedded XY strip structure was developed, obtained by segmenting both the mesh and the anode in perpendicular directions. This results in a very low-mass device with good energy and spatial resolution capabilities. Such a detector is practically “transparent” to neutrons, being ideal for in-beam neutron measurements and can be used as a quasi-online neutron beam profiler at neutron time-of-flight facilities. A dedicated front end electronics and acquisition system has been developed and used. The first studies of this new detection system are presented and discussed
Progress on the PICOSEC-Micromegas Detector Development : Towards a precise timing, radiation hard, large-scale particle detector with segmented readout
This contribution describes the PICOSEC-Micromegas detector which achieves a time resolution below 25 ps. In this device the passage of a charged particle produces Cherenkov photons in a radiator, which then generate electrons in a photocathode and these photoelectrons enter a two-stage Micromegas with a reduced drift region and a typical anode region. The results from single-channel prototypes (demonstrating a time resolution of 24 ps for minimum ionizing particles, and 76 ps for single photoelectrons), the understanding of the detector in terms of detailed simulations and a phenomenological model, the issues of robustness and how they are tackled, and preliminary results from a multi-channel prototype are presented (demonstrating that a timing resolution similar to that of the single-channel device is feasible for all points across the area covered by a multi-channel device).Peer reviewe
Charged particle timing at sub-25 picosecond precision : The PICOSEC detection concept
The PICOSEC detection concept consists in a “two-stage” Micromegas detector coupled to a Cherenkov radiator and equipped with a photocathode. A proof of concept has already been tested: a single-photoelectron response of 76 ps has been measured with a femtosecond UV laser at CEA/IRAMIS, while a time resolution of 24 ps with a mean yield of 10.4 photoelectrons has been measured for 150 GeV muons at the CERN SPS H4 secondary line. This work will present the main results of this prototype and the performance of the different detector configurations tested in 2016-18 beam campaigns: readouts (bulk, resistive, multipad) and photocathodes (metallic+CsI, pure metallic, diamond). Finally, the prospects for building a demonstrator based on PICOSEC detection concept for future experiments will be discussed. In particular, the scaling strategies for a large area coverage with a multichannel readout plane, the R&D on solid converters for building a robust photocathode and the different resistive configurations for a robust readout.Peer reviewe
Timing performance of a Micro-Channel-Plate Photomultiplier Tube
The spatial dependence of the timing performance of the R3809U-50 Micro-Channel-Plate PMT (MCP-PMT) by Hamamatsu was studied in high energy muon beams. Particle position information is provided by a GEM tracker telescope, while timing is measured relative to a second MCP-PMT, identical in construction. In the inner part of the circular active area (radius r5.5 mm) the time resolution of the two MCP-PMTs combined is better than 10 ps. The signal amplitude decreases in the outer region due to less light reaching the photocathode, resulting in a worse time resolution. The observed radial dependence is in quantitative agreement with a dedicated simulation. With this characterization, the suitability of MCP-PMTs as t0 reference detectors has been validated.Peer reviewe
Precise charged particle timing with the PICOSEC detector
The experimental requirements in near future accelerators (e.g. High Luminosity-LHC) has stimulated intense interestin development of detectors with high precision timing capabilities. With this as a goal, a new detection concept called PICOSEC,which is based to a “two-stage” MicroMegas detector coupled to a Cherenkov radiator equipped with a photocathode has beendeveloped. Results obtained with this new detector yield a time resolution of 24 ps for 150 GeV muons and 76 ps for single pho-toelectrons. In this paper we will report on the performance of the PICOSEC in test beams, as well as simulation studies andmodelling of its timing characteristicsPeer reviewe
Precise timing with the PICOSEC-Micromegas detector
This work presents the concept of the PICOSEC-Micromegas de-tector to achieve a time resolution below 30 ps. PICOSEC consists of a two-stageMicromegas detector coupled to a Cherenkov radiator and equipped with a photo-cathode. The results from single-channel prototypes as well as the understanding ofthe detector in terms of detailed simulations and preliminary results from a multi-channel prototype are presented.Peer reviewe
Precise timing and recent advancements with segmented anode PICOSEC Micromegas prototypes
Timing information in current and future accelerator facilities is important
for resolving objects (particle tracks, showers, etc.) in extreme large
particles multiplicities on the detection systems. The PICOSEC Micromegas
detector has demonstrated the ability to time 150\,GeV muons with a sub-25\,ps
precision. Driven by detailed simulation studies and a phenomenological model
which describes stochastically the dynamics of the signal formation, new
PICOSEC designs were developed that significantly improve the timing
performance of the detector. PICOSEC prototypes with reduced drift gap size
(\SI{119}{\micro\metre}) achieved a resolution of 45\,ps in timing single
photons in laser beam tests (in comparison to 76\,ps of the standard PICOSEC
detector). Towards large area detectors, multi-pad PICOSEC prototypes with
segmented anodes has been developed and studied. Extensive tests in particle
beams revealed that the multi-pad PICOSEC technology provides also very precise
timing, even when the induced signal is shared among several neighbouring pads.
Furthermore, new signal processing algorithms have been developed, which can be
applied during data acquisition and provide real time, precise timing.Comment: 5 pages, 3 figures, 12th International Conference on Position
Sensitive Detector
Observation of a nuclear recoil peak at the 100 eV scale induced by neutron capture
Coherent elastic neutrino-nucleus scattering and low-mass Dark Matter
detectors rely crucially on the understanding of their response to nuclear
recoils. We report the first observation of a nuclear recoil peak at around 112
eV induced by neutron capture. The measurement was performed with a CaWO
cryogenic detector from the NUCLEUS experiment exposed to a Cf source
placed in a compact moderator. The measured spectrum is found in agreement with
simulations and the expected peak structure from the single-
de-excitation of W is identified with 3 significance. This
result demonstrates a new method for precise, in-situ, and non-intrusive
calibration of low-threshold experiments