Logo
ScienceStack
Table of Contents
Fetching ...
Sign In

Doubly Charmed Baryon Production in Hadronic Experiments

A. V. Berezhnoy, V. V. Kiselev, A. K. Likhoded, A. I. Onishchenko

TL;DR

The paper computes leading-order perturbative QCD cross sections for producing doubly charmed baryons $Ξ_{cc}^{(*)}$ in hadronic collisions using a two-stage mechanism: hard $gg\to cc\bar{c}\bar{c}$ or $q\bar{q}\to cc\bar{c}\bar{c}$ production followed by nonperturbative binding of the $cc$ diquark into a $Ξ_{cc}$-type baryon. It analyzes fragmentation versus recombination contributions, includes the diquark color and spin projections via $R_{cc}(0)$, and explores uncertainties in $α_s$, $m_c$, and hadronization, proposing to normalize to $J/Ψ+D\bar{D}$ to reduce these uncertainties. The results show strong suppression of $Ξ_{cc}$ production at fixed-target energies ($σ_{(cc)}/σ_{charm} \sim 10^{-6}-10^{-5}$) but much larger yields at collider energies ($\sim 10^{-4}-10^{-3}$), with predicted event counts ranging from about $10^0$ at E781 to $\sim 10^9$ at the LHC. The study discusses collider prospects, fragmentation effects, and possible contributions from intrinsic charm, highlighting how measurements at different facilities could discriminate production mechanisms and improve understanding of heavy-quark dynamics.

Abstract

In the leading order of perturbative QCD one calculates the total and differential cross-sections for the hadronic production of doubly charmed baryons $Ξ_{cc}$ and $Ξ_{cc}^*$ in different experiments. The experimental evaluation of cross-sections for the $J/Ψ+D + \bar D$ production would allow one to decrease the uncertainty in the determination of cross-sections for the doubly charmed baryons due to the choice of $α_s$ and $m_c$. One shows that in the HERA-B and E781 experiments with fixed tagets the suppression of the $Ξ_{cc}$ and $Ξ_{cc}^*$ production to the yield of $c \bar c$-pairs is the value of the order of $10^{-6}-10^{-5}$, whereas at the TEVATRON and LHC colliders it is about $10^{-4}-10^{-3}$. In the E781 experiment the observation of $Ξ_{cc}$ and $Ξ_{cc}^*$ is practically unpossible. At the HERA-B and TEVATRON facilities one can expect $10^5$ events with the double charm, and at LHC one has about $10^9$ ones.

Doubly Charmed Baryon Production in Hadronic Experiments

TL;DR

The paper computes leading-order perturbative QCD cross sections for producing doubly charmed baryons in hadronic collisions using a two-stage mechanism: hard or production followed by nonperturbative binding of the diquark into a -type baryon. It analyzes fragmentation versus recombination contributions, includes the diquark color and spin projections via , and explores uncertainties in , , and hadronization, proposing to normalize to to reduce these uncertainties. The results show strong suppression of production at fixed-target energies () but much larger yields at collider energies (), with predicted event counts ranging from about at E781 to at the LHC. The study discusses collider prospects, fragmentation effects, and possible contributions from intrinsic charm, highlighting how measurements at different facilities could discriminate production mechanisms and improve understanding of heavy-quark dynamics.

Abstract

In the leading order of perturbative QCD one calculates the total and differential cross-sections for the hadronic production of doubly charmed baryons and in different experiments. The experimental evaluation of cross-sections for the production would allow one to decrease the uncertainty in the determination of cross-sections for the doubly charmed baryons due to the choice of and . One shows that in the HERA-B and E781 experiments with fixed tagets the suppression of the and production to the yield of -pairs is the value of the order of , whereas at the TEVATRON and LHC colliders it is about . In the E781 experiment the observation of and is practically unpossible. At the HERA-B and TEVATRON facilities one can expect events with the double charm, and at LHC one has about ones.

Paper Structure

This paper contains 5 sections, 13 equations, 12 figures, 1 table.

Table of Contents

  1. Introduction
  2. Production Mechanism
  3. Doubly Charmed Baryon Production in Fixed Target Experiments
  4. Production of (ccq)-baryon at Colliders
  5. Discussion

Figures (12)

  • Figure 1: The examples of diagrams for the gluon-gluon and quark-antiquark production of $(cc)$-diquark. The initial quarks are denoted by the thin fermion lines, the final quarks are denoted by the bold fermion lines and the gluons are denoted by the helical lines.
  • Figure 2: The total cross-section of the gluon-gluon production of $(cc)$-diquark (solid triangle) and $J/\Psi+D\bar{D}$ (empty triangle) in comparison with the approximations of (8) and (10) (solid and dashed curves, correspondingly).
  • Figure 3: The total cross-section of the quark-antiquark production of $(cc)$-diquark (solid triangle) and $J/\Psi+D\bar{D}$ (empty triangle) in comparison with the approximations of (9) and (11) (solid and dashed curves, correspondingly).
  • Figure 4: The differential cross-section for the associated production of $J/\Psi+c\bar{c}$ in the gluon-gluon subprocess at 100 GeV (solid histogram) in comparison with the prediction of fragmentation model (dashed curve), correspondingly.
  • Figure 5: The total cross-section of the pion-proton production of $(cc)$-diquark and $J/\Psi+D\bar{D}$ (solid and dashed curves, correspondingly).
  • ...and 7 more figures