Experimental Physics Division (EPD) seminar 
Title: Radiation damage studies in LHCb vertex detector 
Speaker: Dr.Shanzhen Chen (INFN-Cagliari) 
Time: 14:00,Tuesday 8th January 2019 
Location: C305 main building 
Indico: https://indico.ihep.ac.cn/event/9231/ 

Abstract: 
LHCb is a dedicated experiment to study New Physics in the decays of heavy hadrons at the Large Hadron Collider (LHC) at CERN. The LHCb detector includes a high precision tracking system consisting of a silicon-strip vertex detector (VELO) surrounding the pp interaction region, a large-area silicon-strip detector located upstream of a dipole magnet and three stations of silicon-strip detectors and straw drift tubes placed downstream of the magnet. Calorimeters, RICH and Muon detectors for particle identification complement the detector. 
The LHC has just finished its run-2 operation in December 2018, and the end of run-2 has seen the VELO detector soak up an incredible 10 fb-1 of luminosity during the past 10 years while continuing to operate at full efficiency. The extreme proximity (~8 mm) of the VELO sensors to the LHC beam renders the VELO an ideal laboratory to study the effects of radiation damage on silicon detectors. To ensure efficient operation, the radiation damage effects were studied closely with several methods. In this presentation, the studies of radiation damage effects, as well as the operational experience of VELO from LHC run-2, and the operational challenges for the silicon detectors in LHC run-2 will be discussed. 

About the speaker: 
Dr. Shanzhen Chen is a post-doctoral researcher from INFN, He obtained his PhD at the University of Manchester. His work includes CP violation searches in multi-body charm decays, production measurements in heavy ion collisions at LHCb, and LHCb vertex locator (VELO) radiation damage and data quality studies. He is the person responsible for VELO charge collection efficiency (CCE) scan and the related analyses, and he determined the run-2 operational voltages for each VELO sensor.