Project
RPCADVANCE : Advancement of the RPC detector technology targeting CERN experiments and applications for society
Code CERN-FIS-INS-0009-2019
Beneficiary Entity
LIP - Laboratório de Instrumentação e Física Experimental de Partículas
Project summary
The aim of this project is to advance the resistive plate chamber (RPC) detector technology to a new level by addressing state-of-the-art challenges that will have direct impact on Nuclear, Astroparticle and High Energy Physics (HEP) experiments (and recognized experiments) at CERN, but also in areas such as health and homeland security.
Our group accumulates more than twenty years of experience in the development of RPCs. We participated in the R&D for the time-of-flight (TOF) detector of the ALICE experiment, within which we co-invented the timing RPCs (tRPC). In addition, the group has contributed to the field with innovative developments: large area tRPCs, multi-hit tRPCs, high counting-rate tRPCs, tRPCs for Positron Emission Tomography (PET), high-accuracy position sensitive (PS) tRPCs, low gas flow RPCs, large area fast-neutron tRPCs and PS thermal-neutron detectors based on RPCs.
This project addresses three challenges on state-of-the-art RPC technology: large area ultra low gas consumption (eventually sealed) RPCs, medium area RPCs offering simultaneous accurate measurement of timing and two-dimensional position, and medium area high rate tRPC.
Large RPC devices used in HEP experiments such as ATLAS and CMS, rely on re-circulation and purification gas systems that require addition of quantities of fresh gas of the order of 6 cc/min/m2, which makes them complex, expensive. Moreover, EU regulations to phase out fluorinated gases are expected to cause a high increase in price and limited availability. Enabling operation of RPCs in an ultra low gas flow regime (eventually sealed) will bring a breakthrough in HEP and particularly in Astroparticle experiments, opening up new possibilities, for example, by making possible installation of stations equipped with RPC detectors in unattended remote locations in future experiments such as LATTES/SWGO. Our group leads this development in the framework of the AUGER collaboration, operating RPCs at 2 cc/min/m2 by using the sealed glass stack (SGS) concept. Our goal is toimprove these devices to enable their operation in ultra low gas flow (< 0.5 cc/min/m2) regime by modifying the construction of the SGS, which is the limiting factor for further reduction of the flow. As a further step we will aim at developing RPCs that will only require infrequent gas exchange ultimately sealed.
The simultaneous measurement of timing and position of a particle with an accuracy of 80 ps and 40 um, respectively, was first demonstrated by our group for a small area detector (60 cm2). Achieving this accuracy in large areas (>1m2) will be of great interest. In HEP experiments this technology could revolutionize particle identification by simultaneous TOF and tracking of the particles, in the health domain in TOF-PET or in homeland security in muon tomography for nuclear threats detection in cargo volumes. Our goal is to implement the concept in a detector prototype with an area more than ten times larger compared to the previously achieved one (~ 1000 cm2) while providing a comparable accuracy.
Typically, tRPCs have a limited counting rate capability (< 1 kHz/cm2) imposed by the electrical resistivity of the electrodes used in its construction. Improvement of the counting rate capability by factors of 20 to 100 has already been achieved in small area detectors (< 100 cm2) by using electrode materials with lower resistivity. However, implementation in medium/large areas remains a challenge due to lack of homogeneity of the materials used, resulting in an unstable behaviour. Increasing the counting rate capability of tRPCs is of great interest for future HEP experiments at CERN due to the growing demand to increase the rate capabilities and timing accuracy driven by high luminosity machines. Our goal is to build a medium area (1000 cm2) high counting rate tRPC (~10 kHz/cm2) by implementing new suitable materials or by reducing the resistivity of the currently used ones by increasing the operational temperature of the detector.
The combination of all (or a part) of these advances in a single device will be a major achievement. This is especially true in the case of the PS neutron detectors based on RPCs, developed by our group, where the combination of high counting rate and accurate position (and timing) readout has a strong potential to make this technology one of the solidest candidates for future applications. In neutron scattering science (NSS) experiments planned for the high-flux neutron sources such as the European Spallation Source, as well as in homeland security, geology and industrial neutron imaging. In the frame of this project, we will explore the possibility of applying the neutron RPC technology in NSS and in the characterization of the delayed neutron emission probability in very exotic nuclei beta decay with a perspective of its application at the ISOLDE experiment at CERN.
Support under
Reforçar a investigação, o desenvolvimento tecnológico e a inovação
Region of Intervention
...
