CMS: Measurement of the jet mass in highly boosted tt events from pp collisions at √s = 8TeV

Authors

S. Chatrchyan
Ekaterina Avdeeva, University of Nebraska-LincolnFollow
Kenneth Bloom, University of Nebraska-LincolnFollow
S. Bose, University of Nebraska - LincolnFollow
Jamila Butt, University of Nebraska - Lincoln
Daniel R. Claes, University of Nebraska-LincolnFollow
Aaron Dominguez, University of Nebraska-LincolnFollow
M. Eads, University of Nebraska-Lincoln, Lincoln,Follow
R. Gonzalez Suarez, University of Nebraska - Lincoln
P. Jindal, University of Nebraska - Lincoln
J. Keller, University of Nebraska - LincolnFollow
D. Knowlton, University of Nebraska-LincolnFollow
Ilya Kravchenko, University of Nebraska-LincolnFollow
Jose Lazo-Flores, University of Nebraska-LincolnFollow
Helena Malbouisson, University of Nebraska - Lincoln
Sudhir Malik, University of Nebraska - LincolnFollow
F. Meier, University of Nebraska-Lincoln, Lincoln,Follow
Gregory Snow, University of Nebraska - LincolnFollow

Date of this Version

2017

Citation

Eur. Phys. J. C (2017) 77:467

Comments

© CERN for the benefit of the CMS collaboration 2017.

Open access

DOI 10.1140/epjc/s10052-017-5030-3

Abstract

The first measurement of the jet mass m_jet of √top quark jets produced in tt events from pp collisions at √s = 8 TeV is reported for the jet with the largest transverse momentum p_T in highly boosted hadronic top quark decays. The data sample, collected with the CMS detector, corresponds to an integrated luminosity of 19.7 fb⁻¹. The measurement is performed in the lepton+jets channel in which the products of the semileptonic decay t → bW with W → lν where l is an electron or muon, are used to select tt events with large Lorentz boosts. The products of the fully hadronic decay t → bW with W → qq are reconstructed using a single Cambridge–Aachen jet with distance parameter R = 1.2, and p_T > 400 GeV. The tt cross section as a function of m_jet is unfolded at the particle level and is used to test the modelling of highly boosted top quark production. The peak position of the m_jet distribution is sensitive to the top quark mass m_t, and the data are used to extract a value of mt to assess this sensitivity.