Measurement of exclusive pion pair production in proton-proton collisions at $\sqrt{s}=7$ TeV with the ATLAS detector

Abstract

The exclusive production of pion pairs in the process $pp\to pp{\pi }^{+}{\pi }^{-}$ has been measured at $\sqrt{s}$ = 7 TeV with the ATLAS detector at the LHC, using 80 $\mu$b${}^{-1}$ of low-luminosity data. The pion pairs were detected in the ATLAS central detector while outgoing protons were measured in the forward ATLAS ALFA detector system. This represents the first use of proton tagging to measure an exclusive hadronic final state at the LHC. A cross-section measurement is performed in two kinematic regions defined by the proton momenta, the pion rapidities and transverse momenta, and the pion-pion invariant mass. Cross section values of $4.8\pm 1.0\text{(stat.)}+{}_{-0.2}^{+0.3}\text{(syst.)}\mu$b and $9\pm 6\text{(stat.)}+{}_{-2}^{+2}\text{(syst.)}\mu$b are obtained in the two regions; they are compared with theoretical models and provide a demonstration of the feasibility of measurements of this type.

arXiv comment39 pages, 10 figures, 5 tables. Figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-07/. Version v2 added link to public web page of results. Version v3 and v4 include minor updates after the journal review

References in corpus (23)

• A Brief Introduction to PYTHIA 8.1
• The ATLAS Simulation Infrastructure
• Charged-particle multiplicities in pp interactions measured with the ATLAS detector at the LHC
• Measurement of the total cross section from elastic scattering in $pp$ collisions at $\sqrt{s}=7$ TeV with the ATLAS detector
• Central Exclusive Particle Production at High Energy Hadron Colliders
• Study of Monte Carlo approach to experimental uncertainty propagation with MSTW 2008 PDFs
• Exclusive physics at the LHC with SuperChic 2
• Diffraction at the LHC
• Exclusive $pp\to pp{\pi }^{+}{\pi }^{-}$ reaction: from the threshold to LHC
• Central exclusive diffractive production of ${\pi }^{+}{\pi }^{-}$ continuum, scalar and tensor resonances in $pp$ and $p\bar{p}$ scattering within tensor pomeron approach
• Global parameterization of $\pi \pi$ scattering up to 2 GeV
• Photoproduction of pi+ pi- pairs in a model with tensor-pomeron and vector-odderon exchange
• Modeling exclusive meson pair production at hadron colliders
• The ALFA Roman Pot Detectors of ATLAS
• The ${\rho }^0$ and Drell-Söding contributions to central exclusive production of ${\pi }^{+}{\pi }^{-}$ pairs in proton-proton collisions at high energies
• Multiple interactions and rapidity gap survival
• Measurement of the central exclusive production of charged particle pairs in proton-proton collisions at $\sqrt{s}=200$ GeV with the STAR detector at RHIC
• Study of central exclusive ${\pi }^{+}{\pi }^{-}$ production in proton-proton collisions at $\sqrt{s}=$ 5.02 and 13 TeV
• The ground state of the Pomeron and its decays to light mesons and photons
• GenEx: A simple generator structure for exclusive processes in high energy collisions
• Pomeron Physics and QCD
• Visualizations of the Exclusive Central Diffraction
• Central exclusive diffractive production of two-pion continuum at hadron colliders

Cited by in corpus (1)

• Physics perspectives of a CMS near-beam proton spectrometer at the HL-LHC