Exclusive pi+ pi- production at 7TeV

Apr 12, 2016, 5:10 PM
SR4b (DESY Hamburg)


DESY Hamburg

Small-x, Diffraction and Vector Mesons WG5 Small-x and Diffraction


Mohsen Khakzad (Institute for Studies in Theoretical Physics & Mathematics (IPM) in Tehran, Iran)


We report a measurement of exclusive pion pair production in proton-proton collisions, dominated by $p + p \rightarrow p^{(*)} + \pi^{+} \pi^{-} + p^{(*)}$, where the $\pi^{+} \pi^{-}$ pair is produced at central rapidities $y$ and the incident protons stay intact or dissociate without being detected. The measurement is performed with the CMS detector at the LHC, using 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 $p_{T}(\pi)>0.2$~GeV/c and $|y(\pi)|< 2$ is $20.5~\pm{0.3~(stat)}~\pm {3.1~(syst)}~\pm~{0.8~(lumi)}~\mu b$. The differential $\pi^{+}\pi^{-}$ cross sections as a function of invariant mass, $p_{T}$, and $y$, and the single $\pi$ cross section as a function of $p_{T}$, are also shown and compared to model predictions.

Primary author

Prof. Collaboration CMS (CINCO)

Presentation materials