Eur. Phys. J. C (2008) 53: 139-166
https://doi.org/10.1140/epjc/s10052-007-0459-4

Special Article - Scientific Note

Design, performance, and calibration of CMS forward calorimeter wedges

¹ Yerevan Physics Institute, Yerevan, Armenia
² NCPHEP, Minsk, Belarus
³ Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Science, Sofia, Bulgaria
⁴ Sofia University, Sofia, Bulgaria
⁵ KFKI-RMKI, Research Institute for Particle and Nuclear Physics, Budapest, Hungary
⁶ ATOMKI, Debrecen, Hungary
⁷ Panjab University, Chandigarh, 160 014, India
⁸ Tata Institute of Fundamental Research, Mumbai, India
⁹ Institute for Studies in Theoretical Physics and Mathematics, Sharif University of Technology, Tehran, Iran
¹⁰ INFN-Trieste, Trieste, Italy
¹¹ JINR, Dubna, Russia
¹² ITEP, Moscow, Russia
¹³ Moscow State University, Moscow, Russia
¹⁴ IHEP, Protvino, Russia
¹⁵ CERN, Geneva, Switzerland
¹⁶ Cukurova University, Adana, Turkey
¹⁷ Middle East Technical University, Ankara, Turkey
¹⁸ Bogazici University, Istanbul, Turkey
¹⁹ KIPT, Kharkov, Ukraine
²⁰ Single Crystal Institute, Kharkov, Ukraine
²¹ Iowa State University, Ames, IA, USA
²² Fermi National Accelerator Laboratory, Batavia, IL, USA
²³ Boston University, Boston, MA, USA
²⁴ University of Illinois at Chicago, Chicago, IL, USA
²⁵ University of Maryland, College Park, MD, USA
²⁶ Fairfield University, Fairfield, CT, USA
²⁷ University of Iowa, Iowa City, IA, USA
²⁸ Department of Physics, Texas Tech University, Lubbock, 79409, TX, USA
²⁹ Florida Institute of Technology, Melbourne, FL, USA
³⁰ Florida International University, Miami, FL, USA
³¹ University of Minnesota, Minneapolis, MN, USA
³² University of Mississippi, Oxford, MS, USA
³³ University of Notre Dame, Notre Dame, IN, USA
³⁴ Princeton University, Princeton, NJ, USA
³⁵ University of Rochester, Rochester, NY, USA
³⁶ Florida State University, Tallahassee, FL, USA
³⁷ Purdue University, West Lafayette, IN, USA
³⁸ Mugla University, Mugla, Turkey
³⁹ Marmara University, Istanbul, Turkey
⁴⁰ Kafkas University, Kars, Turkey
⁴¹ Suleyman Demirel University, Isparta, Turkey

^* e-mail: Nural.Akchurin@ttu.edu

Received: 13 June 2007
Revised: 10 September 2007
Published online: 15 November 2007

Abstract

We report on the test beam results and calibration methods using high energy electrons, pions and muons with the CMS forward calorimeter (HF). The HF calorimeter covers a large pseudorapidity region (), and is essential for a large number of physics channels with missing transverse energy. It is also expected to play a prominent role in the measurement of forward tagging jets in weak boson fusion channels in Higgs production. The HF calorimeter is based on steel absorber with embedded fused-silica-core optical fibers where Cherenkov radiation forms the basis of signal generation. Thus, the detector is essentially sensitive only to the electromagnetic shower core and is highly non-compensating (e/h≈5). This feature is also manifest in narrow and relatively short showers compared to similar calorimeters based on ionization. The choice of fused-silica optical fibers as active material is dictated by its exceptional radiation hardness. The electromagnetic energy resolution is dominated by photoelectron statistics and can be expressed in the customary form as . The stochastic term a is 198% and the constant term b is 9%. The hadronic energy resolution is largely determined by the fluctuations in the neutral pion production in showers, and when it is expressed as in the electromagnetic case, a = 280% and b = 11%.