The performance of electromagnetic calorimeter modules made of proton-irradiated PbWO4 crystals has been studied in beam tests. The modules, similar to those used in the Endcaps of the CMS electromagnetic calorimeter (ECAL), were formed from 5×5 matrices of PbWO4 crystals, which had previously been exposed to 24 GeV protons up to integrated fluences between 2.1 × 1013 and 1.3 × 1014 cm-2. These correspond to the predicted charged-hadron fluences in the ECAL Endcaps at pseudorapidity η = 2.6 after about 500 fb-1 and 3000 fb-1 respectively, corresponding to the end of the LHC and High Luminosity LHC operation periods. The irradiated crystals have a lower light transmission for wavelengths corresponding to the scintillation light, and a correspondingly reduced light output. A comparison with four crystals irradiated in situ in CMS showed no significant rate dependence of hadron-induced damage. A degradation of the energy resolution and a non-linear response to electron showers are observed in damaged crystals. Direct measurements of the light output from the crystals show the amplitude decreasing and pulse becoming faster as the fluence increases. The latter is interpreted, through comparison with simulation, as a side-effect of the degradation in light transmission. The experimental results obtained can be used to estimate the long term performance of the CMS ECAL.
Bibliographical noteFunding Information:
aUniversity of Athens, Panepistimiopolis, Ilissia, Athens, 15771 Greece bInstitute of High Energy Physics, 19B Yuquan Lu, Shijingshan District, Beijing, 100049 China cUniversity of Bristol, Senate House, Tyndall Ave, Bristol, BS8 1TH United Kingdom dBrunel University, Kingston Ln, Uxbridge, Middlesex, UB8 3PH United Kingdom eUniversité libre de Bruxelles, Franklin Rooseveltlaan 50, Bruxelles, 1050 Belgium fCalifornia Institute of Technology, 1200 E California Blvd, Pasadena, CA, 91125 U.S.A. gCarnegie Mellon University, 5000 Forbes Ave, Pittsburgh, Pennsylvania, 15213 U.S.A. hCERN, European Organization for Nuclear Research, Geneva 23, CH-1211 Switzerland jNational Central University, No. 300, Zhongda Rd, Chung-Li, 320 Taiwan kCornell University, 144 East Ave., Ithaca, New York, 14850 U.S.A. lUniversity of Delhi, Delhi, 110007 India mInstitute of Nuclear Physics ‘Demokritos’, 27 Neapoleos str., Attiki, Athens, Greece nJoint Institute for Nuclear Research, Joliot-Curie, 6, Dubna, Russia
oFermi National Accelerator Laboratory, Wilson Street & Kirk Road, Batavia, Illinois, 60510 U.S.A. pFlorida State University, 600 W College Ave, Tallahassee, Florida, 32306 U.S.A. rKansas State University, Manhattan, Kansas, 66506 U.S.A. sSaha Institute of Nuclear Physics, Block-AF, Sector-1, Bidhan nagar, Kolkata, West Bengal, 700064 India tLaboratório de Instrumentação e Física Experimental de Partículas, Av. Elias Garcia 14, Lisboa, 1000 Portugal uImperial College, University of London, London, SW7 2AZ United Kingdom vInstitut de Physique Nucléaire, IN2P3-CNRS and Université C. Bernard Lyon I, 4 Rue Enrico Fermi, Villeurbanne, 69622 France wINFN Sezione di Milano-Bicocca and Università di Milano-Bicocca, Piazza della Scienza 3, Milano, 20126 Italy xUniversity of Minnesota, 3 Morrill Hall 100 Church St. S.E., Minneapolis, Minnesota, U.S.A. yResearch Institute for Nuclear Problems, Byelorussian State University, Bobruiskaya str. 11, Minsk, 220030 Belarus zMassachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, Massachusetts, 02139 U.S.A. aaInstitute for Nuclear Research, Russian Academy of Sciences, 60th October Anniversary pr., 7a, Moscow, 117312 Russia abInstitute for Theoretical and Experimental Physics, Bolshaya Cheremushkinskaya ul., Moscow, 25c2 Russia acUniversity of Cyprus, 1 Panepistimiou Avenue, Aglantzia, Nicosia, 2109 Cyprus adNortheastern University, 360 Huntington Ave, Boston, Massachusetts, 02115 U.S.A. aeUniversity of Notre Dame, Notre Dame, Indiana, 46556 U.S.A. afINFN-Sezione di Pisa, Largo Bruno Pontecorvo, 3, Pisa, 56127 Italy agLaboratoire Leprince-Ringuet, Ecole Polytechnique, Avenue Chasles, Palaiseau, Cedex 91120 France ahPrinceton University, Princeton, New Jersey, 08544 U.S.A. aiState Research Center of Russian Federation — Institute for High Energy Physics, Protvino, Moscow, 142281 Russia ajPaul Scherrer Institut (PSI), Villigen, 5232 Switzerland akRutherford Appleton Laboratory, Science and Technology Facilities Council, Harwell Campus, Didcot, OX11 0QX United Kingdom alINFN Sezione di Roma and Sapienza Università di Roma, P.le Aldo Moro, 2, Roma, 00185 Italy
amDSM/DAPNIA, CEA/Saclay, Gif-sur-Yvette, Cedex 91191 France anUniversidade Estadual Paulista, R. Pamplona, 145, São Paulo, Brazil aoInstitute of Systems Engineering and Robotics, G. Bonchev str., Sofia, Bulgaria apUniversity of Split, Faculty of Electrical Engineering, Mechanical Engineering and Naval Architecture, R. BoökoviÊa 32, Split, 21000 Croatia aqUniversity of Split, Faculty of Science, Livanjska 5, Split, 21000 Croatia arNational Taiwan University, 4, Roosevelt Rd, Da’an District, Taipei, Taiwan asTexas A&M University, 400 Bizzell St, College Station, Texas, 77840 U.S.A. atBhabha Atomic Research Centre, Trombay, Mumbai, India auINFN Sezione di Torino, Università di Torino, Via Pietro Giuria, 1, Torino, 10125 Italy avINFN Sezione di Trieste and Università di Trieste, Padriciano, 99, Trieste, 34149 Italy awUniversity of California, Gilman Dr., San Diego, California, 9500 U.S.A. ax‘Vinca’ Institute of Nuclear Sciences and Faculty of Physics of University of Belgrade, P.O. Box 522, Belgrade, 11001 Serbia ayThe University of Virginia, Charlottesville, Virginia, 22904-4246 U.S.A. azInstitute for Particle Physics, ETH Zurich, Otto-Stern-Weg 5, Zurich, 8093 Switzerland baUniversità del Piemonte Orientale, Via Duomo, 6, Novara, 13100 Italy
© CERN 2016.
- Detector modelling and simulations I (interaction of radiation with matter, interaction of photons with matter, interaction of hadrons with matter, etc)
- Radiation-hard detectors
- Scintillation and light emission processes (solid, gas and liquid scintillators)