Cosmic Test Of STGC Detector And Study Of NSW Muon Reconstruction

The discovery in July 2012 by the A Toroidal Large Hadron Collider Apparatus(ATLAS)[2]and Compact Muon Solenoid(CMS)experi-ments[3]at the Large Hadron Collider(LHC)[1]of a new particle with mass of 125 GeV and properties compatible with the Higges boson[5][6]predicted by the Standard Model(SM)[4]is a major milestone in Particle Physics.After The discovery of Higges boson,upgrades are needed for both the LHC and ATLAS,CMS experiment to study the property of higgs and search for new physics.The upgrade of LHC is mainly to increase hit rate,which lead to high background radiation.The upgrade lead to higher requirements on the performance of the detector,and some detectors need to be replaced because they cannot meet the requirements.The upgrade of ATLAS experiment separate into 2 part,called Phase-? and Phase-?.To meet the challenge of increasing hit rate and high luminosity,Phase-? upgrade mainly dealing with the fake trigger in the ATLAS end cap,Phase-? upgrade will replace most silicon detec-tors,colorimeter and muon systems,as well as the related electronics.Muon spectrometer at the ATLAS end cap,consists of a disc of three layers muon detectors(a small wheel and two big wheels)and the cor-responding magnet system.SW consist of MDT,TGC and CSC.BW consist of MDT detector.The muon trigger system consists of three layers of TGC,TGC provide triggers by rough muon deflection.The muon system upgrade in phase-I uses NSW(new SW)consisting of MM and sTGC detectors to replace the original SW detector.NSW as the main part of the ATLAS Phase-I upgrade requires to be able reduce the fake trigger by reconstruct the track direction and able reconstruct the precision muon tracking under high radiation background.This talk will cover the sTGC detector cosmic test and the anal-ysis of NSW simulation.This talk shows the performance of sTGC detector by cosmic test,and the performance of NSW simulation by adding the factors in real detector to simulation data.And this talk also shows the muon track reconstruction ability of NSW system,which is of prospective significance for understanding the performance and later calibration of NSW system.This paper introduces the structure of sTGC detector,the cosmic test system,the DAQ and data analysis.The position resolution,de-tection efficiency and alignment correction of the tested sTGC are in-troduced in detail.As a result,all the tests were summarized for the sTGC detector.The paper also introduces the muon simulation of the NSW system,the performance of the ideal NSW,and the effect on the NSW performance after introducing the actual detector factors.