A novel application of Fiber Bragg Grating (FBG) sensors in MPGD

¹ RWTH Aachen University, III Physikalisches Institut A, Aachen, Germany
² INFN Bari and University of Bari, Bari, Italy
³ Peking University, Beijing, China
⁴ INFN Bologna and University of Bologna, Bologna, Italy
⁵ Universite Libre de Bruxelles, Brussels, Belgium
⁶ National Institute of Science Education and Research, Bhubaneswar
⁷ Institute for Particle and Nuclear Physics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, Budapest, Hungary
⁸ Academy of Scientific Research and Technology - Egyptian Network of High Energy Physics, ASRT-ENHEP, Cairo, Egypt
⁹ Texas A&M University, College Station, U.S.A.
¹⁰ Institute for Nuclear Research of the Hungarian Academy of Sciences (ATOMKI), Debrecen, Hungary
¹¹ University of Delhi, Delhi, India
¹² Wayne State University, Detroit, U.S.A
¹³ Texas A&M University at Qatar, Doha, Qatar
¹⁴ ENEA - Frascati Research Centre, Frascati RM- Italy
¹⁵ Laboratori Nazionali di Frascati - INFN, Frascati, Italy
¹⁶ University of Florida, Gainesville, U.S.A.
¹⁷ Petersburg Nuclear Physics Institute, Gatchina, Russia
¹⁸ CERN, Geneva, Switzerland
¹⁹ Ghent University, Dept. of Physics and Astronomy, Ghent, Belgium
²⁰ National Center for Physics, Quaid-i-Azam University Campus, Islamabad, Pakistan
²¹ Saha Institute of Nuclear Physics, Kolkata, India
²² Lappeenranta University of Technology, Lappeenranta, Finland
²³ University of California, Los Angeles, U.S.A.
²⁴ Florida Institute of Technology, Melbourne, U.S.A.
²⁵ Bhabha Atomic Research Centre, Mumbai, India
²⁶ INFN Napoli, Napoli, Italy
²⁷ INFN Pavia and University of Pavia, Pavia, Italy
²⁸ University of Rome “La Sapienza” (IT) - Facoltà di Ingegneria, Ingegneria Chimica Materiali ed Ambiente, Roma, Italy
²⁹ IRFU CEA-Saclay, Saclay, France
³⁰ Institute for Nuclear Research and Nuclear Energy, Sofia, Bulgaria
³¹ Sofia University, Sofia, Bulgaria
³² Korea University, Seoul, Korea
³³ Seoul National University, Seoul, Korea
³⁴ University of Seoul, Seoul, Korea
³⁵ Institut Pluridisciplinaire - Hubert Curien (IPHC), Strasbourg, France

^a Corresponding author; email address: Luigi.Benussi@lnf.infn.it

Published online: 21 February 2018

Abstract

We present a novel application of Fiber Bragg Grating (FBG) sensors in the construction and characterisation of Micro Pattern Gaseous Detector (MPGD), with particular attention to the realisation of the largest triple (Gas electron Multiplier) GEM chambers so far operated, the GE1/1 chambers of the CMS experiment at LHC. The GE1/1 CMS project consists of 144 GEM chambers of about 0.5 m² active area each, employing three GEM foils per chamber, to be installed in the forward region of the CMS endcap during the long shutdown of LHC in 2108-2019. The large active area of each GE1/1 chamber consists of GEM foils that are mechanically stretched in order to secure their flatness and the consequent uniform performance of the GE1/1 chamber across its whole active surface. So far FBGs have been used in high energy physics mainly as high precision positioning and re-positioning sensors and as low cost, easy to mount, low space consuming temperature sensors. FBGs are also commonly used for very precise strain measurements in material studies. In this work we present a novel use of FBGs as flatness and mechanical tensioning sensors applied to the wide GEM foils of the GE1/1 chambers. A network of FBG sensors have been used to determine the optimal mechanical tension applied and to characterise the mechanical tension that should be applied to the foils. We discuss the results of the test done on a full-sized GE1/1 final prototype, the studies done to fully characterise the GEM material, how this information was used to define a standard assembly procedure and possible future developments.