1,244 research outputs found
Gain, Rate and Position Resolution Limits of Micropattern Gaseous Detectors
In this study we report the results of a systematic study of the gain, rate
and the position resolution limits of various micropattern gaseous detectors.
It was found that at low rates (<1 Hz/mm^2) each detector has it own gain
limit, which depends on the size and design features, as well as on gas
composition and pressure. However, in all cases the maximum achievable gain is
less than or equal to the classical Raether limit. It also was found that for
all detectors tested the maximum achievable gain drops sharply with the
counting rate. The position resolution of micropattern detectors for detection
of X-rays (6 to 35 kV) was also studied, being demonstrated that with solid
converters one could reach a position resolution better than 30 micrometers at
1 atm in a simple counting mode.Comment: 10 pages, 3 figures, Presented at the PSD99-5th International
Conference on Position-Sensitive Detectors, 13-17 th September 1999,
University College, Londo
Detection of the primary scintillation light from dense Ar, Kr and Xe with novel photosensitive gaseous detectors
The detection of primary scintillation light in combination with the charge
or secondary scintillation signals is an efficient technique to determine the
events t=0 as well as particle / photon separation in large mass TPC detectors
filled with noble gases and/or condensed noble gases. The aim of this work is
to demonstrate that costly photo-multipliers could be replaced by cheap novel
photosensitive gaseous detectors: wire counters, GEMs or glass capillary tubes
coupled with CsI photocathodes. We have performed systematic measurements with
Ar, Kr and Xe gas at pressures in the range of 1-50 atm as well as some
preliminary measurements with liquid Xe and liquid Ar. With the gaseous
detectors we succeeded in detecting scintillation light produced by 22 keV
X-rays with an efficiency of close to 100%. We also detected the scintillation
light produced by bs (5 keV deposit energy) with an efficiency close to 25%.
Successful detection of scintillation from 22 keV gammas open new experimental
possibilities not only for nTOF and ICARUS experiments, but also in others,
like WIMPs search through nuclear recoil emission
Progress in Developing Hybrid RPCs: GEM-like Detectors with Resistive Electrodes
We have recently developed an innovative detector of photons and charged
particles: a GEM-like gaseous amplification structure with resistive electrodes
instead of commonly used metallic ones. This novel detector combines the best
property of GEMs- the capability to operate in a cascaded mode and in poorly
quenched gases - and of RPC: the protection against sparks. In this paper will
shortly review our latest achievements in this direction, however the main
focus will be given on a new advanced design that allows to build large area
detectors manufactured by a screen printing technology. The proposed detector,
depending on the applications, can operate either in a GEM mode (electron
multiplications through holes only) or as a hybrid RPC with simultaneous
amplifications in the drift region and in the holes. The possible applications
of this new detector will be discussed
Gain limits of a Thick GEM in high-purity Ne, Ar and Xe
The dependence of the avalanche charge gain in Thick Gas Electron Multipliers
(THGEM) on the purity of Ne, Ar and Xe filling gases was investigated. The
gain, measured with alpha-particles in standard conditions (atmospheric
pressure, room temperature), was found to considerably drop in gases purified
by non-evaporable getters. On the other hand, small N2 admixtures to noble
gases resulted in high reachable gains. The results are of general relevance in
the operation of gas-avalanche detectors in noble gases, particularly that of
two-phase cryogenic detectors for rare events.Comment: 15 pages, 6 figures, submitted to JINS
Further developments and tests of microstrip gas counters with resistive electrodes
We present results from further tests of Microstrip Gas Counters (MSGCs) with
resistive electrodes. The maim advantage of this detector is that it is
spark-protected: in contrast to "classical" MSGCs with metallic electrodes,
sparks in this new detector do not destroy its electrodes. As a consequence the
MSGC with resistive electrodes is more reliable in operation which may open new
avenues in applications. One of them which is under investigation now is the
use of Resistive electrodes MSGC (R-MSGC) as photodetector in some particular
designs of noble liquid dark matter detectors.Comment: Presented at the RD-51 mini-week at CERN, January 17, 201
An improved design of spark-protected microstrip gas counters (R-MSGC)
We have developed microstrip gas counters manufactured on standard printed
circuit board and having the following features: resistive cathode strips, thin
(10 micron) metallic anode strips and electrodes protected against surface
discharges by a Coverlay layer at their edges. These features allow the
detector to operate at gas gains as high as can be achieve with the best
microstrip gas counters manufactured on glass substrates. We believe that after
further developments this type of detectors can compete in some applications
with other micropattern detectors, for example MICROMEGAS.Comment: Presented at the 7th RD51 Collaboration meeting, CERN, April 201
First Tests of Gaseous Detectors Made of a Resistive Mesh
We describe here various detectors designs: GEM type, MICROMEGAStype,
PPACtype as well as cascaded detectors made of a resistive mesh manufactured
from a resistive Kapton foil, (20 microns thick, resistivity a few MOhm per
square) by a laser drilling technique. As in any other micropattern detectors
the maximum achievable gas gain of these detectors is restricted by the Raether
limit, however, the resistive mesh makes them and the front end electronics
fully spark protected. This approach could be an alternative or complimentary
to the ongoing efforts in developing MICROMEGAS and GEMs with resistive anode
readout plates and can be especially beneficial in the case of micropattern
detectors combined with a micropixel-type integrated front end electronic
High-resolution TOF with RPCs
In this work, we describe some recent results concerning the application of Resistive Plate Chambers operated in avalanche mode at atmospheric pressure for high-resolution time-of-flight measurements. A combination of multiple, mechanically accurate, thin gas gaps and state-of-the-art electronics yielded an overall (detector plus electronics) timing accuracy better than 50Â ps [sigma] with a detection efficiency up to 99% for MIPs. Single gap chambers were also tested in order to clarify experimentally several aspects of the mode of operation of these detectors. These results open perspectives of affordable and reliable high granularity large area TOF detectors, with an efficiency and time resolution comparable to the existing scintillator-based TOF technology but with a significantly, up to an order of magnitude, lower price per channel.http://www.sciencedirect.com/science/article/B6TJM-45F4WHB-7/1/95e90d633532cd93d712a5bfad6b902
Demonstration of new possibilities of multilayer technology on resistive microstrip/ microdot detectors
The first successful attempts to optimize the electric field in Resistive
Microstrip Gas Chamber and resistive microdot detectors using additional field
shaping strips located inside the detector substrate are describedComment: Presented at the RD-51 mmini week, CERN, June 201
On the physics and technology of gaseous particle detectors
Despite an already long and fruitful history, gaseous elementary-particle
detectors remain today an important mainstay of high-energy and nuclear physics
experiments and of radiation detection in general. In here we briefly describe
some of the gaseous detector's main technologies and applications, along with
some unsolved gas-discharge physics aspects of practical relevance.Comment: Submitted to Plasma Sources in Science and Technolog
- …