The Optical Instrumentation of the ATLAS Tile Calorimeter The ATLAS Tile Calorimeter Community

The Optical Instrumentation of the ATLAS Tile Calorimeter The ATLAS Tile Calorimeter Community J Abdallah25, P Adragna17, C Alexa6, R Alves13, P Amaral11,12, A Ananiev28, K Anderson7, X Andresen11,12, A Antonaki3, V Batusov9, P Bednar5, E Bergeaas22, C Biscarat8, O Blanch4, G Blanchot4, C Bohm22, V Boldea6, F Bosi17, M Bosman4, C Bromberg10, J Budagov9, D Calvet8, C Cardeira28, T Carli11, J Carvalho13, M Cascella17, M V Castillo25, J Costelo25, M Cavalli-Sforza4, V Cavasinni17, A S Cerqueira21, C Clement22,11, M Cobal11, F Cogswell24, S Constantinescu6, D Costanzo17, P Da Silva21, M David12, T Davidek18,11, J Dawson1, K De2, T Del Prete17, E Diakov27, B Di Girolamo11, S Dita6, J Dolejsi18, Z Dolezal18, A Dotti17, R Downing24, G Drake1, I Efthymiopoulos11, D Errede24, S Errede24, A Farbin7,11, D Fassouliotis3, E Feng7, A Fenyuk20, C Ferdi8, B.C Ferreira21, A Ferrer25, V Flaminio17, J Flix4, P Francavilla17, E Fullana25, V Garde8, K Gellerstedt22, V Giakoumopoulou3, V Giangiobbe17, O Gildemeister11, V Gilewsky15, N Giokaris3, N Gollub11, A Gomes12, V Gonzalez25, J Gouveia28, P Grenier11,8, P Gris8, V Guarino1, C Guicheney8, A Gupta7, H Hakobyan26, M Haney24, S Hellman22, A Henriques11, E Higon25, N Hill1, S Holmgren22, I Hruska19, M Hurwitz7, J Huston10, I Jen-La Plante7, K Jon-And22, T Junk24, A Karyukhin20, J Khubua9,23, J Klereborn22, V Konsnantinov20, S Kopikov20, I Korolkov4, P Krivkova18, Y Kulchitsky9,15, Yu Kurochkin15, P Kuzhir16, V Lapin20*, T LeCompte1, R Lefevre8, R Leitner18, J Li2, M Liablin9, M Lokajicek19, Y Lomakin9*, P Lourtie28, L Lovas5, A Lupi17, C Maidantchik21, A Maio12, S Maliukov9, A Manousakis3, C Marques12, F Marroquim21, F Martin11,8, E Mazzoni17, F Merritt7, A Miagkov20, R Miller10, I Minashvili9, L Miralles4, G Montarou8, S Nemecek19, M Nessi11, I Nikitine20, L Nodulman1, O Norniella4, A Onofre14, M Oreglia7, B Palan19, D Pallin8, D Pantea6, A Pereira13, J Pilcher7, J Pina12, J.Pinhao13, E Pod7, F Podlyski8, X Portell4, J Poveda25, L Pribyl19, L E Price1, J Proudfoot1, M Ramalho28, M Ramstedt22, L Raposeiro28, J Reis28, R Richards10, C Roda17, V Romanov9, R Rosnet8, P Roy8, A Ruiz25, V Rumiantsau16*, N Russakovich9, J Sa da Costa28, O Salto4, B Salvachua25, E Sanchis25, H Sanders7, C Santoni8, J Santos12, J G Saraiva12, F Sarri17, L.-P Says8, G Schlager11, J Schlereth1, J M Seixas21, B Sellden22, N Shalanda20, P Shevtsov16, M Shochet7, J Silva12, V Simaitis24, M Simonyan26, A Sissakian9, J Sjoelin22, C Solans25, A Solodkov20, O Solovianov20, M Sosebee2, F Spano17,11, P Speckmeyer11, R Stanek1, E Starchenko20,P Starovoitov16, M Suk18, I Sykora5, F Tang7, P Tas18, R Teuscher7, M Tischenko27, S Tokar5, N Topilin9, J Torres25, D Underwood1, G Usai17, A Valero25, S Valkar18, J A Valls25, A Vartapetian2, F Vazielle8, C Vellidis3, F Ventura28, I Vichou24, I Vivarelli17, M Volpi4, A White2, A Zaitsev20, Yu Zaytsev27, A Zenin20, T Zenis5, Z Zenonos17, S Zenz7, B Zilka5 Argonne National Laboratory, Argonne, Illinois 60439 USA University of Texas at Arlington, Arlington, Texas 76019 USA University of Athens, Athens, Greece Institute de Fisica d'Altes Energies, Universitat Autonoma de Barcelona, Barcelona, Spain Comenius University, Bratislava, Slovakia Institute of Atomic Physics, Bucharest, Romania University of Chicago, Chicago, Illinois 60637 USA LPC Clermont-Ferrand, Universite Blaise Pascal / CNRS-IN2P3, Clermont-Ferrand, France JINR, Dubna, Russia 10 Michigan State University, East Lansing, Michigan 48824 USA 11 CERN, Geneva, Switzerland 12 LIP and FCUL Univ of Lisbon, Portugal 13 LIP and FCTUC Univ of Coimbra, Portugal 14 LIP and Univ Catolica Figueira da Foz, Portugal 15 Institute of Physics, National Academy of Sciences, Minsk, Belarus 16 National Centre of Particles and High Energy Physics, Minsk, Belarus Pisa University and INFN, Pisa, Italy 18 Charles University in Prague, Prague, Czech Republic 19 Institute of Physics, Academy of Sciences of the Czech Republic, Prague, Czech Republic 20 Institute for High Energy Physics, Protvino, Russia 21 COPPE/EE/UFRJ, Rio de Janeiro, Brazil 22 Stockholm University, Stockholm, Sweden 23 HEPI, Tbilisi State Univ., Tbilisi, Georgia 24 University of Illinois, Urbana-Champaign, Illinois 61801 USA 25 IFIC, Centro Mixto Universidad de Valencia-CSIC, E46100 Burjassot, Valencia, Spain 26 Yerevan Physics Institute, Yerevan, Armenia 27 SIA Luch, Podolsk, Russia 28 LIP and IDMEC-IST, Lisbon, Portugal * Deceased 17 Introduction The ATLAS Tile Calorimeter (TileCal), in conjunction with the Liquid Argon Calorimeters, provides essentially full absorption of the energy of jets for pseudorapidity |η| < 4.9 TileCal is divided into three cylindrical structures, extending altogether over the interval < |η| < 1.7 The design of this system is described in detail in the “ATLAS Tile Calorimeter Technical Design Report” [1] An overall view of the calorimetric system of ATLAS is given in Fig 1, which also shows the central and the two external cylinders of TileCal, which are referred to as the Barrel and Extended Barrels respectively Fig 1: The Calorimetric system of the ATLAS experiment at the CERN Large Hadron Collider Each of the three Barrels is segmented in azimuth into 64 modules, which were constructed and tested in separate production lines Module construction consisted of two main phases: the mechanical assembly of the steel absorber structure of each module, and the assembly into this structure of the active optical components – scintillators and fibers - that detect the particles produced in the hadronic showers The purpose of this report is to describe the optical assembly procedure – called here Optical Instrumentation – and the quality tests conducted on the assembled units Altogether, 65 Barrel (or LB) modules were constructed – including one spare – together with 129 Extended Barrel (EB) modules (including one spare) The LB modules were mechanically assembled at JINR (Dubna, Russia) and transported to CERN, where the optical instrumentation was performed with personnel contributed by several Institutes The modules composing one of the two Extended Barrels (known as EBA) were mechanically assembled in the USA, and instrumented in two US locations (ANL, Michigan State University), while the modules of the other Extended barrel (EBC) were assembled in Spain and instrumented at IFAE (Barcelona) A detailed description of module construction is given in Ref [2] General features of the optical instrumentation The layout of the readout cells in the Barrel and Extended Barrel calorimeters, together with the properties of the optical components used in equipping the modules, are crucial factors in determining the instrumentation procedures and the quality obtained These aspects are briefly described in this section 2.1 Cell segmentation Scintillator tiles are organized in 11 tile rows of different sizes The scintillation light generated in tiles is collected at the exposed edges of each tile by wave-length shifting (WLS) fibers, arranged in pre-shaped opaque plastic “profiles” Within each module, readout cells are defined by grouping together bundles of fibers which are then coupled to a photo multiplier (PMT) Each fiber bundle thus brings to a PMT the light from a group of tiles that spans part of the longitudinal and transverse extent of hadronic showers The light from each cell is read out by two PMTs, which detect the light from the two exposed sides of each module The segmentation of the LB and EB modules into four types of cells/sub-cells – A, BC and D, from inner to outer radius - is shown in Figures and 3, from Ref [3] In the Barrel, the B and C sub-cells are read out by the same PMT Fig Layout of cells in the Barrel (LB) modules The bottom of the picture corresponds to the inner radius For each cell, the long and short fiber lengths are given, in cm, together with the number of fibers of each type For each cell, the number of the PMT that reads it out is also given Cells of type A and B are numbered according to pseudorapidity – for instance, cell B-4 covers the interval -0.4 < η