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arXiv · 2004.04213

$Λ_c^{\pm}$ production in pp collisions with a new fragmentation function

B. A. Kniehl·G. Kramer·I. Schienbein·H. Spiesberger
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Abstract

We study inclusive $Λ_c^{\pm}$-baryon production in $pp$ collisions in the general-mass variable-flavor number scheme and compare with data from the LHCb, ALICE and CMS collaborations. We perform a new fit of the $c \to Λ_c^+$ fragmentation function combining $e^+e^-$ data from OPAL and Belle. The agreement with LHC data is slightly worse compared with a calculation using an older fragmentation function, and the tension between different determinations of $Λ_c^{\pm}$ production cross sections from the LHC experimental collaborations is not resolved. The ratio of data for $Λ_c^+$-baryon and $D^0$-meson production seems to violate the universality of $c$-charm quark to $c$-hadron fragmentation.

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B. A. Kniehl, G. Kramer, I. Schienbein, H. Spiesberger. 2020-04-08. $Λ_c^{\pm}$ production in pp collisions with a new fragmentation function. https://doi.org/10.1103/physrevd.101.114021

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