Neutron GEM-based detectors represent a new frontier of diagnostic devices in neutron-linked physics applications such as detectors for fusion experiments (Croci et al., 2012 1) and spallation ...sources (Murtas et al., 2012 2). Besides, detectors installed in HEP experiments (like LHC at CERN) are dip in a high flux neutron field. For example, the TOTEM T2 GEM telescope (Bagliesi et al., 2010 3) at LHC is currently installed very close to the beam pipe where a high intensity (>104ncm−2s−1) neutron background is present. In order to assess the capability (particularly related to discharge probability) of working in intense neutrons environment, a 10×10cm2 Triple GEM detector has been tested using a high flux (105ncm−2s−1) neutron beam. The neutron-induced discharge probability PDisch was measured to be 1.37×10−7 at an effective gain G=5×104. In addition, the different types of neutron interactions within the detector were fully explained through a GEANT4 simulation.
With the tenfold luminosity increase envisaged at the HL-LHC, the background (i.e., photons, neutrons, \ldots ) and the event pileup probability are expected to highly increase in proportion in the ...different experiments, especially in the forward regions, for instance the muons chambers of the ATLAS detector. Detectors based on the Micromegas principle should be good alternatives for the detector upgrade in the HL-LHC framework because of its good spatial (< 100\mu{\hbox{m}}) and time (few ns) resolutions, high-rate capability, radiation hardness, good robustness, and the possibility to build large areas. The aim of this study is to demonstrate that it is possible to reduce the discharge probability and protect the electronics by using a resistive anode plane in a high-flux hadrons environment. Several prototypes of 10 \times 10~{\hbox{cm}}^{2} , with different pitches (0.5-2 mm) and different resistive layers have been tested at CERN (\pi^{+}@{\rm SPS}) . Several tests have been performed with a telescope at different voltages to assess the performance of the detectors in terms of position resolution and efficiency. The spark behavior in these conditions has also been evaluated. Resistive coating has been shown to be a successful method to reduce the effect of sparks on the efficiency of micromegas. A good spatial resolution (\sim 80\ \mu{\hbox{m}}) can be reached with a resistive strip coating detector of 1-mm pitch, and a high efficiency ( > 98\%) can be achieved with resistive-anode micromegas detector. An X-rays irradiation has also been performed, showing no ageing effect after more than 21 days exposure and an integrated charge of almost 1C.
With the tenfold luminosity increase envisaged at the HL-LHC, the background (photons, neutrons, ...) and the event pile-up probability are expected to increase in proportion in the different ...experiments, especially in the forward regions like, for instance, the muons chambers of the ATLAS detector. Detectors based on the Micromegas 1 principle should be good alternatives for the detector upgrade in the HL-LHC framework because of a good spatial (<;100μm) and time (few ns) resolutions, high-rate capability, radiation hardness, good robustness and the possibility to build large areas. The aim of this study is to demonstrate that it is possible to reduce the discharge probability and protect the electronics by using a resistive anode plane in a high flux hadrons environment. Several prototypes of 10×10 cm 2 , with different pitches (0.5 to 2 mm) and different resistive layers have been tested at CERN (π + @SPS). Several tests have been performed with a telescope at different voltages to assess the performances of the detectors in terms of position resolution and efficiency. The spark behaviour in these conditions has also been evaluated. Resistive coating has been shown to be a successful method to reduce the effect of sparks on the efficiency of micromegas. A good spatial resolution (~ 80μm) can be reached with a resistive strip coating detector of 1mm pitch and a high efficiency (>; 98%) can be achieved with resistive-anode micromegas detector. An X-rays irradiation has been also performed, showing no ageing effect after more than 21 days exposure and an integrated charge of almost 1C.
With the tenfold luminosity increase envisaged at the HL-LHC, the background (photons, neutrons, ...) and the event pile-up probability are expected to increase in proportion in the different ...experiments, especially in the forward regions like, for instance, the muons chambers of the ATLAS detector. Detectors based on the Micromegas principle should be good alternatives for the detector upgrade in the HL-LHC framework because of a good spatial (<100 \mum) and time (few ns) resolutions, high-rate capability, radiation hardness, good robustness and the possibility to build large areas. The aim of this study is to demonstrate that it is possible to reduce the discharge probability and protect the electronics by using a resistive anode plane in a high flux hadrons environment. Several prototypes of 10x10 cm2, with different pitches (0.5 to 2 mm) and different resistive layers have been tested at CERN (pi+@SPS). Several tests have been performed with a telescope at different voltages to assess the performances of the detectors in terms of position resolution and efficiency. The spark behaviour in these conditions has also been evaluated. Resistive coating has been shown to be a successful method to reduce the effect of sparks on the efficiency of micromegas. A good spatial resolution (~80 \mum) can be reached with a resistive strip coating detector of 1mm pitch and a high efficiency (> 98%) can be achieved with resistive-anode micromegas detector. An X-rays irradiation has been also performed, showing no ageing effect after more than 21 days exposure and an integrated charge of almost 1C.
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