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arXiv · 1904.05004

Evidence in favor of Single Parton Scattering mechanism in $\Upsilon$ and $D$ associated production at the LHC

Anton Karpishkov·Maxim Nefedov·Vladimir Saleev
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Abstract

Associated production of prompt $\Upsilon(1S)$ and $D^{+,0}$ mesons has been proposed as a golden channel for the search of Double Parton Scattering, because Single Parton Scattering contribution to the cross-section is believed to be negligible on a basis of leading order calculations in the Collinear Parton Model. We study this process in the leading order approximation of the Parton Reggeization Approach. Hadronization of $b\bar{b}$-pair into bottomonium states is described within framework of the NRQCD-factorization approach while production of $D$ mesons is described in the fragmentation model with scale-dependent fragmentation functions. We have found good agreement with LHCb data for various normalized differential distributions, except for the case of spectra on azimuthal angle differences at the small $\Delta\varphi$ values. Crucially, the total cross-section in our Single Parton Scattering model accounts for more than one half of observed cross-section, thus dramatically shrinking the room for Double Parton Scattering mechanism.

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Anton Karpishkov, Maxim Nefedov, Vladimir Saleev. 2019-04-10. Evidence in favor of Single Parton Scattering mechanism in $\Upsilon$ and $D$ associated production at the LHC. https://doi.org/10.1103/physrevd.99.096021

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