FILIPPO RESNATI. Study of Resistive Plate Chambers for applications in High Energy Physics Supervisor: Prof. Dr. Stefano Ragazzi

Transcription

1 FILIPPO RESNATI Address: 15/R-001 Phone: +41 (0) CERN CH-1211 Geneva 23 Switzerland website: EDUCATION Doctor of Philosophy in Physics June 2012 Eidgenössische Technische Hochschule Zürich (Switzerland) Modeling, design and first operation of the novel double phase LAr LEM-TPC detector Supervisor: Prof. Dr. André Rubbia Master s Degree in Physics December 2007 Università degli studi di Milano - Bicocca (Italy) 110/110 cum laude Study of liquid argon detectors for Dark Matter searches Supervisor: Prof. Dr. Tommaso Tabarelli de Fatis Bachelor s Degree in Physics December 2004 Università degli studi di Milano - Bicocca (Italy) 110/110 cum laude Study of Resistive Plate Chambers for applications in High Energy Physics Supervisor: Prof. Dr. Stefano Ragazzi POSITIONS HELD Fellow at CERN March 2014 present Associate at ESS March 2014 present Postdoc at ETH Zurich July 2012 February 2014 PROFESSIONAL EXPERIENCES 2014 present: R&D on MicroPattern Gaseous Detectors MicroPattern Gaseous Detectors (MPGDs) are flexible and widespread devices with promising performances for next generation High Energy Physics experiments, as well as for medical applications, dosimetry purposes and neutron detection. The most well-known types of MPGDs are the Gaseous Electron Multiplier (GEM) and MicroMeGas (MM). Good position resolution, high particle flux capability, radiation tolerance, low material budget, cost-effectiveness, large surfaces and low energy threshold are the key features of MPGDs. The future Linear Collider detectors and the upgrade of the CMS, ATLAS and ALICE detectors foresee their use. Beyond the collider experiments, MPGDs can be used in a large variety of applications and to detect different particles at different energies. For instance, solid converters can be coupled to MPGDs in order to make them sensitive to neutrons. In fact, GEM detectors will be used for the NMX instrument at ESS. RD-51 is the largest collaboration for the development of gaseous detectors. Its role is to provide common facilities and a framework for the knowledge circulation, strengthening the international collaborations, in order to effectively overcome the present technological limitations and disseminate the results of the specific developments. At CERN I am involved in several projects and I m leading few of them: 1/6

2 Study the intrinsic limits of GEM detectors in terms of extreme particle flux, and find ways to push them further. Development of precise timing detectors based on MM for pileup mitigation in future collider experiments. Development of an alternative, intuitive and immediate readout for MPGDs, that can be used in a number of applications. In collaboration with ESS: Development of neutron detectors with unprecedented spatial (and time) resolution based on Boron and Gadolinium converters. R&D targeted to the Neutron Macromolecular Crystallography instrument (NMX) at ESS and production of a fully functional demonstrator within the European Union-funded project BrightnESS : R&D on liquid argon based detectors The liquid argon Time Projection Chamber (TPC) is a 3D imaging and calorimetric device. It has been used for neutrino experiments (e.g. ICARUS) and it will be used for DUNE, the future long baseline neutrino oscillation experiment. In order to improve the signal to noise ratio, the overall image quality, the 3D reconstruction capabilities and the energy resolution, the signal can be amplified directly in the detector. The amplification is obtained in argon vapour by means of the Large Electron Multiplier (LEM), a cheap and robust scaled-up version of the GEMs. During my PhD, I developed a 3 L active volume detector, which is considered the proof of principle of the double phase (liquid-vapour) argon LEM-TPC technology. Following the solutions developed for this small detector, we could build and successfully operate a 200 L prototype with an active area of cm 2. It demonstrated the scalability of the technical solutions found for the 3 L setup. In the context of R&D towards very large liquid argon TPCs, the knowledge of the dielectric rigidity of liquid argon is fundamental in order to properly design the detector high voltage system. For this reason, I built a test stand where voltages up to 100 kv can be applied. First results showed that the onset of instabilities strongly depends on the presence of argon bubbles in the high field region. Nevertheless, the dielectric rigidity of pure and stable liquid argon is larger than 100 kv/cm : ArDM Argon Dark Matter is a ton scale liquid argon based detector installed in the Laboratorio Subterráneo de Canfranc, seeking direct evidences of Cold Dark Matter in the form of Weakly Interacting Massive Particles (WIMPs). The WIMP, colliding with an argon nucleus, is expected to release energy in the range of kev. Argon allows the simultaneous detection of the scintillation light and the ionisation charge, key feature for the background discrimination. In the period when the detector was in the development and commissioning phase at CERN, I took part in several tests. My contributions were multiple and various, ranging from the production of essential parts (like the high voltage and low voltage feedthroughs), to the design of the trigger system for the first tests underground, the procurement of the related electronics, and the analysis of the data collected on surface at CERN : Development of xenon detectors for homeland security MOdular DEtection System for Special Nuclear Materials (MODES-SNM) was an FP7 funded project aiming at the design, construction and qualification of a mobile system for the detection of unauthorised and undeclared Special Nuclear Materials (SNM), e.g. highly enriched uranium and plutonium. The final system consisted of an array of gamma 2/6

3 and neutron (thermal and fast) detectors. It improved the state of the art in the detection of radioactive sources in terms of sensitivity for shielded SNM. The project delivered a device ready-to-use by the customs officers. In collaboration with industries, I was in charge of the development of the gamma ray detector, which was based on high pressure xenon used as scintillator. I optimised the detector in terms of materials and geometry in order to maximise the energy resolution and the detection efficiency. This was done with a series of systematic measurements and Monte Carlo simulations. 2007: WArP WIMP Argon Program aimed to the direct detection of WIMPs. A 2.3 L liquid argon TPC was the technology demonstrator and the R&D test bench. WArP was pioneering setting an exclusion limit on the WIMP-nucleon cross-section with an argon based detector. I took part in an underground fully operational run to measure the background. I characterised the proportional scintillation signals, fundamental for the background discrimination capabilities of the detector. RESPONSIBILITIES Convener of the Working Group 1 of the RD-51 Collaboration. CERN scientific contact for the European Union-funded project BrightnESS. Leader of Task 4.1 (for which CERN has responsibilities) in the BrightnESS project. FUNDS BrightnESS proposal accepted within the European Commission s Horizon 2020 Research and Innovation programme. BrightnESS is designed to ensure that key challenges are met in order to build an ESS that can deliver high-impact scientific and technological knowledge. 18 partners with a total grant of 20 MEuro, of which CERN receives about 700 keuro in three years. SKILLS Technical Extensive experience in designing, building and operating particle detectors. Expert in handling cryogenic liquids and vacuum equipments. Deep familiarity with a rich variety of laboratory instruments, digital and analog electronics. Experience in operating detectors in test beams and in underground laboratories. Routinely developing software for data analysis and using statistical tools to interpret the results. Everyday experience with simulation packages and tools. Computing Programming: C, C++, L A TEX shell scripting, XHTML and CSS. Analysis and simulation: ROOT, Gnuplot, GEANT4, Garfield, Magboltz and SPICE. Commercial softwares: COMSOL, AutoCAD, Mathematica and EAGLE. Office applications: Apple iwork and Microsoft Office. Operative systems: Mac OS X, Linux and Windows. 3/6

4 Languages Italian: mother tongue. English: fluent. French: intermediate proficiency. PUBLICATIONS, CONFERENCES AND SCHOOLS Publication summary Citeable papers: Number of citations 453. h HEP index 12. Published only: Number of citations 233. h HEP index 8. Selection of peer reviewed papers D. Pfeiffer et al., New High-Resolution Gadolinium-GEM Neutron Detectors for the NMX Instrument at ESS, arxiv: Submitted to NIMA. L. Swiderski et al., Scintillation response of Xe gas studied by gamma-ray absorption and Compton electrons, JINST 10 (2015) 07, P D. Pfeiffer et al., The µtpc Method: Improving the Position Resolution of Neutron Detectors Based on MPGDs, JINST 10 (2015) P C. Cantini et al., Performance study of the effective gain of the double phase liquid Argon LEM Time Projection Chamber, JINST 10 (2015) 03, P C. Cantini et al., Long-term operation of a double phase LAr LEM Time Projection Chamber with a simplified anode and extraction-grid design, JINST 9 (2014) P S.K. Agarwalla et al., The mass-hierarchy and CP-violation discovery reach of the LBNO long-baseline neutrino experiment, JHEP 1405 (2014) 094. A. Badertscher et al., ArDM: first results from underground commissioning, JINST 8 (2013) C A. Badertscher et al., First operation and performance of a 200 lt double phase LAr LEM-TPC with a 40x76 cm 2 readout, JINST 8 (2013) P F. Resnati et al., Suitability of high-pressure xenon as scintillator for gamma ray spectroscopy, Nucl. Instr. Meth. A715 (2013) A. Badertscher et al., First operation and drift field performance of a large area double phase LAr Electron Multiplier Time Projection Chamber with an immersed Greinacher high-voltage multiplier, JINST 7 (2012) P A. Badertscher et al., First operation of a double phase LAr Large Electron Multiplier Time Projection Chamber with a two-dimensional projective readout anode, Nucl. Instr. Meth. A641 (2011) C. Amsler et al., First results on light readout from the 1-ton ArDM liquid argon detector for dark matter searches, JINST 5 (2010) P V. Boccone et al., Development of wavelength shifter coated reflectors for the ArDM argon dark matter detector, JINST 4 (2009) P /6

5 Selection of conference proceedings S. Franchino et al., Effects of High Charge Densities in Multi-GEM Detectors, arxiv: IEEE Proceeding. S. Franchino et al., Charge Transfer Properties Through Graphene for Applications in Gaseous Detectors, arxiv: Pisa Meeting proceeding. F. Bay et al., Evidence of electric breakdown induced by bubbles in liquid argon, arxiv: Proceeding of High Voltage in Noble Liquids. F. Resnati, Pressurised xenon as scintillator for gamma spectroscopy, JINST 8 (2013) C F. Resnati et al., Status of the ArDM experiment, PoS IDM2010 (2011) 108. A. Badertscher et al., Stable operation with gain of a double phase Liquid Argon LEM-TPC with a 1 mm thick segmented LEM, J. Phys. Conf. Ser. 308 (2011) A. Badertscher et al., Operation of a double-phase pure argon Large Electron Multiplier Time Projection Chamber: Comparison of single and double phase operation, Nucl. Instr. Meth. A617 (2010) A. Badertscher et al., Construction and operation of a Double Phase LAr Large Electron Multiplier Time Projection Chamber, Nucl. Sci. Symp. Conf. Rec., NSS 08. IEEE, (2008) Conferences and workshops 4th LNF Workshop on Cylindrical GEM Detectors, Frascati (Italy), November IEEE Nuclear Science Symposium & Medical Imaging Conference, San Diego CA (United States), 1 6 November th Conference on Micro-Pattern Gaseous Detectors, Trieste (Italy), October th Pisa Meeting on Advanced Detectors, Isola d Elba (Italy), May nd Workshop on Neutron Detection with MPGDs, Geneva (Switzerland), March IKON 8, Abingdon (UK), 3 5 February High voltage in Noble Liquids, Batavia IL (United States), 8 9 November International Workshop on Light Detection in Noble Elements, Batavia IL (United States), May th International Workshop on Next generation Nucleon Decay and Neutrino Detectors, Zurich (Switzerland), 7 9 November nd International Workshop towards the Giant Liquid Argon Charge Imaging Experiment, Jyväskylä (Finland), 5 10 June th International Workshop on the Identification of Dark Matter, Montpellier (France), July st International Workshop towards the Giant Liquid Argon Charge Imaging Experiment, Tsukuba (Japan), March Joint Annual Meeting SPS - ÖPG - ÖGAA 2009, Innsbruck (Austria), 2 4 September th Pisa Meeting on Advanced Detectors, Isola d Elba (Italy), May Nuclear Science Symposium, Medical Imaging Conference and 16th Room Temperature Semiconductor Detector Workshop, Dresden (Germany), October /6

6 Schools COMSOL Multiphysics Workshop, Zurich (Switzerland), 2 November RD51 Simulation School, CERN, Genève (Switzerland), January CHIPP PhD Winter School 2011, Leukerbad (Switzerland), 9 14 January AWARDS 2015 NIMA Young Scientist Award dedicated to the memory of Glenn Knoll. OTHER ACTIVITIES Referee for NIM and JINST. In the organising committee of the RD-51 Academia-Industry Matching Event - Special Workshop on Photon Detection with MPGDs. Supervisor of undergraduate and graduate students. Laboratory teacher for graduate students at the Danube School on Instrumentation in Elementary Particle & Nuclear Physics, University of Novi Sad (Serbia), September 8th 13th, Seven semesters as teaching assistant of Physics I, Physics II and Physics Laboratories at Eidgenössische Technische Hochschule Zürich. Tuesday 29 th March, 2016 Filippo Resnati 6/6