Searching for anomalous top quark interactions with proton tagging and timing detectors at the LHC

Abstract

We study the LHC sensitivity to new broad neutral resonances produced in two-photon fusion and decaying to a top quark pair, $\gamma \gamma \to t\bar{t}$. This is probed in central exclusive $t\bar{t}$ production in proton-proton collisions, $pp\to pt\bar{t}p$. We use the tagging of the intact protons by PPS (CMS) and AFP (ATLAS) and consider the semi-leptonic $t\bar{t}$ channel. The sensitivity is also mapped onto a set of dimension-8 $\gamma \gamma t\bar{t}$ operators in the large mass limit. Using the kinematical correlations between the intact protons and the reconstructed $t\bar{t}$ system, we obtain a sensitivity to the couplings of the dimension-8 operators of $1.4\cdot 10^{-11}{\mathrm{GeV}}^{-4}$ at 95% CL. The sensitivity to the anomalous couplings is significantly improved down to about $7\cdot 10^{-12}{\mathrm{GeV}}^{-4}$ if the proton time-of-flight is known with a precision of 20 ps in future measurements. The 95% CL sensitivity to broad neutral resonances reaches masses of order $1500\mathrm{GeV}$ when using timing information.

23 pages, 10 figures

References in corpus (16)

• The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
• Description and performance of track and primary-vertex reconstruction with the CMS tracker
• Performance of electron reconstruction and selection with the CMS detector in proton-proton collisions at sqrt(s) = 8 TeV
• Light scalar at LHC: the Higgs or the dilaton?
• $W^{+}{W}^{-}$ production at hadron colliders in NNLO QCD
• Looking for magnetic monopoles at LHC with diphoton events
• The Excitation of the Global Symmetry-Breaking Vacuum in Composite Higgs Models
• Dark Matter Searches in Jet plus Missing Energy in $\gamma \mathrm{p}$ collision at CERN LHC
• Dimension-six anomalous $tq\gamma$ couplings in $\gamma \gamma$ collision at the LHC
• Analysis of anomalous quartic $WWZ\gamma$ couplings in $\gamma p$ collision at the LHC
• Large Extra Dimension effects through Light-by-Light Scattering at the CERN LHC
• Challenging exclusive top quark pair production at low and high luminosity LHC
• Graviton production through photon-quark scattering at the LHC
• Performance studies of Time-of-Flight detectors at LHC
• The Global Higgs as a Signal for Compositeness at the LHC
• Search for Kaluza-Klein gravitons in extra dimension models via forward detectors at the LHC