Inclusive production of X$\rightarrow b\bar{b}$ plus a recoil for the LHC Run-II

TL;DR

This study evaluates strategies for detecting high-momentum Higgs bosons decaying to b-quark pairs at the LHC, proposing trigger improvements and analyzing sensitivity to Higgs production amid multijet backgrounds.

Contribution

It introduces a trigger strategy for inclusive X→bar{b} production, assessing its effectiveness and robustness for future high-luminosity LHC runs.

Findings

Trigger strategy improves signal efficiency below 200 GeV

Sensitivity to Higgs cross section around 1.8 pb at 100 fb$^{-1}$

Robustness against systematic uncertainties is demonstrated

Abstract

This letter presents a study of the inclusive production of X$\rightarrow b\bar{b}$ plus a recoil, using simulated samples of $pp$ collisions at $\sqrt{s}=14$ TeV for an integrated luminosity in the range between 30 fb$^{-1}$ to 3 ab$^{-1}$. The case for experiments to include un-prescaled $b$-tag multijet triggers for this topology is made and the ideal jet thresholds are discussed. The sensitivity to Standard Model Higgs with a transverse momentum of at least 200 GeV is evaluated with respect to a continuous background, dominated by multijet processes. The mass of $b$-jet-pairs is analysed, quoting sensitivity to cross-sections in the range of 1 to 2 pb, for 100 fb$^{-1}$, covering the Higgs production cross section of 1.8 pb. The trigger strategy presented in this letter is compared to triggers already in use, showing an increase on the signal efficiency for masses below 200 GeV and a performance comparable to a logic OR of all the currently available akin triggers for higher masses. The robustness of the expected sensitivity against systematic uncertainties is estimated by considering various typical sources, such as those on the fitting parameters of the continuous background, shape uncertainties affecting the signal acceptance and the background modelling. The accuracy of a Higgs production cross section measurements is also discussed, quoting sensitivity to deviations of 50% for 100 fb$^{-1}$ and 10% for 3 ab$^{-1}$.