Direct photons as probes of low mass strings at the LHC

Abstract

The LHC program will include the identification of events with single prompt high-k_\perp photons as probes of new physics. We show that this channel is uniquely suited to search for experimental evidence of TeV-scale open string theory. At the parton level, we analyze single photon production in gluon fusion, gg \to γg, with open string states propagating in intermediate channels. If the photon mixes with the gauge boson of the baryon number, which is a common feature of D-brane quivers, the amplitude appears already at the string disk level. It is completely determined by the mixing parameter (which is actually determined in the minimal theory) -- and it is otherwise model-(compactification-) independent. We discuss the string signal cross sections as well as the QCD background. The present analysis takes into account the recently obtained decay widths of first Regge recurrences, which are necessary for more precise determination of these cross sections in the resonant region. A vital part of the background discussion concerns the minimization of misidentified π^0's emerging from high-p_\perp jets. We show that even for relatively small mixing, 100 fb^-1 of LHC data could probe deviations from standard model physics associated with TeV-scale strings at a 5σsignificance, for M_{\rm string} as large as 2.3 TeV. It is also likely that resonant bumps could be observed with approximately the same signal-to-noise ratio.

arXiv commentUpdated to match the published version

References in corpus (23)

• New Generation of Parton Distributions with Uncertainties from Global QCD Analysis
• New Dimensions at a Millimeter to a Fermi and Superstrings at a TeV
• Black Holes at the LHC
• Four-dimensional String Compactifications with D-Branes, Orientifolds and Fluxes
• Multi-Parton Amplitudes in Gauge Theories
• Weak Scale Superstrings
• Group theory factors for Feynman diagrams
• A D-brane alternative to unification
• The Standard Model from Stable Intersecting Brane World Orbifolds
• Black Holes from Cosmic Rays: Probes of Extra Dimensions and New Limits on TeV-Scale Gravity
• TeV Strings and Collider Probes of Large Extra Dimensions
• Black Holes and Quantum Gravity at the LHC
• Multi-Gluon Scattering in Open Superstring Theory
• Strongly Interacting Neutrinos and the Highest Energy Cosmic Rays
• Black Hole Production at LHC: String Balls and Black Holes from pp and Lead-lead Collisions
• Amplitude for N-Gluon Superstring Scattering
• Jet signals for low mass strings at the LHC
• TeV-Scale String Resonances at Hadron Colliders
• The Minimal Quiver Standard Model
• Study of Direct Photon plus Jet production in CMS Experiment at \sqrt{s}=14 TeV
• Identification of photon-tagged jets in the ALICE experiment
• ALICE potential for heavy-flavour physics
• Constraints on String Resonance Amplitudes

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