Title: The High Granularity Calorimeter upgrade project for CMS

Speaker: David Barney (CERN)
Modertator: Prof. Zhang Huaqiao
Time: 14:00, May 13
Place: Room C305, IHEP Main Building

Abstract:

Calorimetry in high-energy physics is rapidly evolving, with new specifications (e.g. higher energies, enormous particle densities) and a wide variety of technologies being employed, both for signal creation and detection. Advances in large-area highly-segmented detectors based on, for example, silicon and scintillators, are providing possibilities for high-granularity calorimetry, providing unprecedented levels of information from particle showers. This talk focuses on one example of high-granularity calorimetry: The CMS HGCAL, being designed to replace the existing endcap calorimeters for the HL-LHC era. It is a sampling calorimeter, featuring unprecedented transverse and longitudinal readout segmentation for both electromagnetic (CE-E) and hadronic (CE-H) compartments. This will facilitate particle-flow calorimetry, where the fine structure of showers can be measured and used to enhance pileup rejection and particle identification, whilst still achieving good energy resolution. The CE-E and a large fraction of CE-H will use silicon as active detector material: the sensors will be of hexagonal shape, maximizing the available 8-inch circular wafer area. The lower-radiation environment will be instrumented with scintillator tiles with on-tile SiPM readout. This concept borrows heavily from designs produced by the CALICE collaboration - calorimetry for CLIC and ILC etc. - but the challenges of such a detector at a hadron collider are considerably larger than at the ILC. In addition to the hardware aspects, the reconstruction of signals - both online for triggering and offline - is a quantum leap from existing detectors. We present the reasoning and ideas behind the HGCAL, its current status including design and expected performance, and the challenges ahead. 

About the speaker:

David Barney (CERN)

CERN Applied Physicist since 1994 for CMS Collaboration

August 1996 – present: CERN Staff member

CERN EP-CMX Group Leader (October 2017 – present)

>40 staff, plus fellows, students, trainees, external members >100 people

CMS HGCAL detector (2015 – present)

Member of Steering Group & Institution Board

Developed draft HGCAL “Constitution”, drawing on experience in ECAL

Formalized HGCAL Editorial Board and Conference Committee, and nominated as Chairperson for both bodies

Responsible for Beam Tests and System Tests,

CMS ECAL detector (2010 – 2015)

ECAL System Manager for Jan. 2013 – Aug. 2015

CMS ECAL Joint Deputy System Manager: 2010 – 2012

member of CMS Management Board (2010 – 2015)

CMS calorimetry Preshower detector (1996 – present)

January 1994 – July 1996: Applied Fellow at CERN

1987 – 1993: Imperial College, London, UK

PhD and Diploma of Imperial College: “Observation of beauty particles in pion-nucleon collisions at 26 GeV centre-of-mass energy”

BSc in Physics with 1st-class honours, and Associateship of the Royal College of Science