Improved b-jet Energy Correction for H→bb¯ Searches at CDF

Timo Antero Aaltonen, A. Buzatu, B. Kilminster, Y. Nagai, W. Yao, CDF Collaboration, D0 Collaboration

Research output: Book/ReportCommissioned reportProfessional

Abstract

We present a method for improving the $b$-jet energy resolution in order to improve the signal sensitivity in searches for particles decaying to a $b$ quark and anti-$b$ quark. A correction function is computed for individual jets, which combines information from the secondary vertex tagger, the offline tracking and standard calorimeter-based jet-energy reconstruction algorithm in order to provide a more accurate measurement of the true $b$-quark energy. We apply the correction to Monte-Carlo-simulated jets in the process $WH \rightarrow \ell \nu b\bar b$ and find an improvement in both the mean and the resolution of the $b$-jet energy with respect to the $b$-quark energy. The correction improves the measured Higgs dijet invariant mass resolution from $\sim$ 15%(standard jet corrections) to $\sim$ 11%(improved jet corrections) in the Higgs mass range from 100 GeV/$c^2$ - 150 GeV/$c^2$. Using the corrected $b$-jet energies instead of the standard calorimeter-based $b$-jet energies results in a $\sim$ 9% improvement in the expected sensitivity for Higgs boson production cross section in the most sensitive search region of the $WH \rightarrow \ell \nu b\bar b$ analysis, which is two tagged jets and one charged central lepton.
Original language English
Publication status Published - Jul 2011 D4 Published development or research report or study

Publication series

Name Fermilab Technical Publications FERMILAB-TM-2513-PPD

Fields of Science

• 114 Physical sciences