No Arabic abstract
Resistive gaseous detectors can be broadly defined as those operated in conditions where virtually no field lines exist that connect any two metallic electrodes sitting at different potential. This condition can be operationally recognized as no gas gap being delimited by two metallic electrodes. Since early 70s, Resistive Plate Chambers (RPCs) are the most successful implementation of this idea, that leads to fully spark-protected gaseous detectors, with solid state-like reliability at working fields beyond 100kV/cm, yet enjoying the general characteristics of gaseous detectors in terms of flexibility, optimization and customization. We present a summary of the status of the field of resistive gaseous detectors as discussed in a dedicated closing session that took place during the XI Workshop for Resistive Plate Chambers and Related Detectors celebrated in Frascati, and especially we review the perspectives and ambitions towards the XII Workshop to be celebrated in Beijing in year 2014. Due to the existence of two specific reviews ([1,2]) also at this workshop, a minimum amount of overlap was found to be unavoidable. We have realized, however, that the three works provide a look at the field from different optics, so they can be largely considered to be complementary. Contrary to the initial concerns, the overall appearance seems to be fairly round, in our opinion.
Gaseous detectors are fundamental components of all present and planned high energy physics experiments. Over the past decade two representatives (GEM, Micromegas) of the Micro-Pattern Gas Detector (MPGD) concept have become increasingly important; the high radiation resistance and excellent spatial and time resolution make them an invaluable tool to confront future detector challenges at the next generation of colliders. Novel structures where GEM and Micromegas are directly coupled to the CMOS multi-pixel readout represent an exciting field and allow to reconstruct fine-granularity, two-dimensional images of physics events. Originally developed for the high energy physics, MPGD applications have expanded to astrophysics, neutrino physics, neutron detection and medical imaging.
The response of RPC detectors is highly sensitive to environmental variables. A novel approach is presented to model the response of RPC detectors in a variety of experimental conditions. The algorithm, based on Artificial Neural Networks, has been developed and tested on the CMS RPC gas gain monitoring system during commissioning.
Since long time, the compelling scientific goals of future high energy physics experiments were a driving factor in the development of advanced detector technologies. A true innovation in detector instrumentation concepts came in 1968, with the development of a fully parallel readout for a large array of sensing elements - the Multiwire Proportional Chamber (MWPC), which earned Georges Charpak a Nobel prize in physics in 1992. Since that time radiation detection and imaging with fast gaseous detectors, capable of economically covering large detection volume with low mass budget, have been playing an important role in many fields of physics. Advances in photo-lithography and micro-processing techniques in the chip industry during the past decade triggered a major transition in the field of gas detectors from wire structures to Micro-Pattern Gas Detector (MPGD) concepts, revolutionizing cell size limitations for many gas detector applications. The high radiation resistance and excellent spatial and time resolution make them an invaluable tool to confront future detector challenges at the next generation of colliders. The design of the new micro-pattern devices appears suitable for industrial production. Novel structures where MPGDs are directly coupled to the CMOS pixel readout represent an exciting field allowing timing and charge measurements as well as precise spatial information in 3D. Originally developed for the high energy physics, MPGD applications has expanded to nuclear physics, UV and visible photon detection, astroparticle and neutrino physics, neutron detection and medical physics.
A new family of spark-protected micropattern gaseous detectors is introduced: a 2-D sensitive restive microstrip counter and hybrid detectors, which combine in one design a resistive GEM with a microstrip detector. These novel detectors have several important advantages over other conventional micropattern detectors and are unique for applications like the readout detectors for dual phase noble liquid TPCs and RICHs.
In-beam evaluation of a fully-equipped medium-size 30$times$30 cm$^2$ Resistive Plate WELL (RPWELL) detector is presented. It consists here of a single element gas-avalanche multiplier with Semitron ESD225 resistive plate, 1 cm$^2$ readout pads and APV25/SRS electronics. Similarly to previous results with small detector prototypes, stable operation at high detection efficiency (>98%) and low average pad multiplicity (~1.2) were recorded with 150 GeV muon and high-rate pion beams, in Ne/(5%CH$_4$), Ar/(5%CH$_4$) and Ar/(7%CO$_2$). This is an important step towards the realization of robust detectors suitable for applications requiring large-area coverage; among them Digital Hadron Calorimetry.