Year-end Sale % OFF 
Abstract
The Preshower detector, part of the CMS Endcap Electromagnetic Calorimeter, is designed to have good spatial resolution to distinguish between photons and neutral pions. The Preshower is a sampling detector with two layers of lead absorber, each followed by 1.9 mm pitch silicon strip sensors. Each of the 4288 DC-coupled sensors has an active area of 61×61 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> , making a total surface area of around 16 m <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . The Preshower was installed and commissioned in CMS in 2009 and has been used in data taking ever since. The design, construction, commissioning and operational experience will be described, including the observation and mitigation of radiation-induced bulk and surface effects. The calibration strategy will also be discussed.
Highlights
The Preshower detector, part of the CMS Endcap Electromagnetic Calorimeter, is designed to have good spatial resolution to distinguish between photons and neutral pions
The Preshower is a sampling detector with two layers of lead absorber, each followed by 1.9 mm pitch silicon strip sensors
Each of the 4288 DC-coupled sensors has an active area of 61x61 mm2, making a total surface area of around 16 m2
Summary
THE Preshower (ES) is installed at each end of CMS, at about ±310 cm from the CMS interaction point, and placed in front of the electromagnetic calorimeter endcap (EE) [1]. The ES has two layers: lead radiators (2X0 and 1X0, respectively) initiate electromagnetic showers from incoming electrons/photons whilst silicon strip sensors placed after each radiator measure the energy deposited and the transverse shower profiles. The silicon sensors are made on 4” float zone, n-type material, with total volume of 63×63×0.32 mm. The silicon sensors are made on 4” float zone, n-type material, with total volume of 63×63×0.32 mm3 They have 32 p+ implanted strips, 1.8 mm wide and at a pitch of 1.9 mm. The ES front-end electronics can operate in two modes: High Gain (HG) is used for precise calibration purposes; Low Gain (LG) has a higher dynamic range more suitable for physics data taking
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
