پديد آورنده :
زينلي، مريم
عنوان :
اندازه گيري تصحيحات وارد بر انرژي جتها در آزمايش CMS با استفاده از اولين برخوردهاي پروتوني در LHC
گرايش تحصيلي :
ذرات بنيادي﴿آزمايشگاهي﴾
محل تحصيل :
اصفهان: دانشگاه صنعتي اصفهان، دانشكده فيزيك
يادداشت :
ص.ع.به فارسي و انگليسي
استاد راهنما :
يورگن دانت، منصور حقيقت
توصيفگر ها :
مدل استاندارد , كوارك تاپ , الكترون , برازشي كينماتيكي , پردازش چند متغيره سرن
تاريخ نمايه سازي :
27/1/91
استاد داور :
فرايابلكمن،الكساندرنيكتينكو، احمد شيرزاد
كد ايرانداك :
ID418 دكتري
چكيده فارسي :
به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي
چكيده انگليسي :
Abstract Calibration of jets are important in the studies of new physics since when jets arebetter calibrated the new physics events can be better reconstructed and di eren tiated from the background In tt W W b e e q q b events the reconstructed b bjets originate from the decay of the W boson and the top quark Since the hadronicpart of tt e jets events hence th W h bh q q bh can be fully reconstructed however the leptonic part being tl W l bl e e bl can not be fully reconstructeddue to the presence of a neutrino in the nal state As the masses of both the Wboson and the top quark have been already measured at LEP and Tevatron withgreat precision therefore the mass values can be used to constrain the system Massconstraints are imposed in an event by event least square technique by means of La grange Multipliers which is referred to as a kinematic t The kinematic t return aprobability which re ects how likely the hypothesis of originating three reconstructedjets from the decay of the top quark is correct The jet energy scale calibration factorsare then adopted so that the probability returned by the kinematic t is maximized The results are obtained based on a simulated data sample corresponding to an in tegrated luminosity of about 100 pb 1 It is shown that the estimated results arecomparable with the expected values among the statistical as well as systematicaluncertainties Since March 2010 the LHC machine has been running at a center of mass energy of7 TeV and the CMS experiment has been collecting the proton collision data Theamount of data collected in 2010 has reached to about 36 1 pb 1 The method is alsoapplied on the 2010 collision data recorded by the CMS experiment and the resultshave been reported Good agreement between simulation and collision data is found The results are statistically limited which can be xed when running the method onlarger amount of statistics collected in the 2011 runs Keywords Standard Model top quark Jets Electron MVA Kinematic Fit CMS LHC CERN
استاد راهنما :
يورگن دانت، منصور حقيقت
استاد داور :
فرايابلكمن،الكساندرنيكتينكو، احمد شيرزاد
