# Top quark mass measurement in the tt̅ all hadronic channel using a matrix element technique in pp̅ collisions at √s=1.96  TeV

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http://hdl.handle.net/10138/24451

#### Citation

Aaltonen , T , Mehtala , P , Orava , R , Maki , T , Saarikko , H & CDF Collaboration 2009 , ' Top quark mass measurement in the tt̅ all hadronic channel using a matrix element technique in pp̅ collisions at √s=1.96  TeV ' , Physical Review D : Particles, Fields, Gravitation and Cosmology , vol. 79 , no. 7 , pp. 072010 . https://doi.org/10.1103/PhysRevD.79.072010

 Title: Top quark mass measurement in the tt̅ all hadronic channel using a matrix element technique in pp̅ collisions at √s=1.96  TeV Alternative title: Top Quark Mass Measurement in the tt-bar All Hadronic Channel using a Matrix Element Technique in ppbar Collisions at sqrt s = 1.96 TeV Author: Aaltonen, T; Mehtala, P; Orava, R; Maki, T; Saarikko, H; CDF Collaboration Contributor organization: Department of PhysicsHelsinki Institute of Physics Date: 2009 Language: eng Number of pages: 28 Belongs to series: Physical Review D : Particles, Fields, Gravitation and Cosmology ISSN: 1550-7998 DOI: https://doi.org/10.1103/PhysRevD.79.072010 URI: http://hdl.handle.net/10138/24451 Abstract: We present a measurement of the top quark mass in the all-hadronic channel (\tt $\to$ \bb$q_{1}\bar{q_{2}}q_{3}\bar{q_{4}}$) using 943 pb$^{-1}$ of \ppbar collisions at $\sqrt {s} = 1.96$ TeV collected at the CDF II detector at Fermilab (CDF). We apply the standard model production and decay matrix-element (ME) to $\ttbar$ candidate events. We calculate per-event probability densities according to the ME calculation and construct template models of signal and background. The scale of the jet energy is calibrated using additional templates formed with the invariant mass of pairs of jets. These templates form an overall likelihood function that depends on the top quark mass and on the jet energy scale (JES). We estimate both by maximizing this function. Given 72 observed events, we measure a top quark mass of 171.1 $\pm$ 3.7 (stat.+JES) $\pm$ 2.1 (syst.) GeV/$c^{2}$. The combined uncertainty on the top quark mass is 4.3 GeV/$c^{2}$.We present a measurement of the top quark mass in the all hadronic channel (tt̅ →bb̅ q1q̅ 2q3q̅ 4) using 943  pb-1 of pp̅ collisions at √s=1.96  TeV collected at the CDF II detector at Fermilab (CDF). We apply the standard model production and decay matrix element (ME) to tt̅ candidate events. We calculate per-event probability densities according to the ME calculation and construct template models of signal and background. The scale of the jet energy is calibrated using additional templates formed with the invariant mass of pairs of jets. These templates form an overall likelihood function that depends on the top quark mass and on the jet energy scale (JES). We estimate both by maximizing this function. Given 72 observed events, we measure a top quark mass of 171.1±3.7(stat+JES)±2.1(syst)  GeV/c2. The combined uncertainty on the top quark mass is 4.3  GeV/c2. Description: submitted to Phys. Rev. D Subject: 114 Physical sciences hep-ex Peer reviewed: Yes Usage restriction: restrictedAccess
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