Exclusive pi+ pi- production at 7TeV

Abstract

We report a measurement of the exclusive production of pairs of charged pions in proton-proton collisions, dominated by the process $pp\to p^{(\ast )}{\pi }^{+}{\pi }^{-}{p}^{(\ast )}$, where ${\mathrm{p}}^{(\ast )}$ stands for a diffractively dissociated proton, the ${\pi }^{+}{\pi }^{-}$ pair is emitted at central rapidities $y$, and the incident protons stay intact or dissociate without detection ${\mathrm{p}}^{(\ast )}$. The measurement is performed with the CMS detector at the LHC, using a data sample corresponding to an integrated luminosity of 450~$\mu$b${}^{-1}$ collected at a center-of-mass energy of $\sqrt{s}$ = 7 TeV in 2010. The cross section measured in the phase space defined by pion transverse momentum $p_{\mathrm{T}}>0.2$~GeV/c and rapidity $|y|<2$ is found to be $20.5\pm 0.3(\mathrm{stat})(\pm 3.1\mathrm{syst})\pm$~0.8~(lumi)~$\mu$b. The differential cross sections for ${\pi }^{+}{\pi }^{-}$ pairs as a function of the pion pair invariant mass, $p_{\mathrm{T}}$, and $y$, as well as a single-pion differential cross section as a function of pion $p_{\mathrm{T}}$ are also measured and compared to several phenomenological predictions.

6 pages, 8 figures, DIS 2016

References in corpus (1)

• Central Exclusive Particle Production at High Energy Hadron Colliders