arXiv 1204.02822012-04nucl-exhep-ex

$\sqrt{s}$ = 7时pp碰撞中多奇异重子的产生

Multi-strange baryon production in pp collisions at $\sqrt{s}$ = 7 TeV with ALICE

ALICE Collaboration

备注：: 15 pages, 4 captioned figures, 2 tables, authors from page 10, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/3100
发表信息：: Phys. Lett. B 712 (2012) 309
DOI：: 10.1016/j.physletb.2012.05.011

摘要：

本文报道了在欧洲核子研究中心（CERN）大型强子对撞机（LHC）上，利用ALICE实验测量了质心能量为7 TeV的质子-质子非弹性碰撞中的多奇异$Ξ^-$和$Ω^-$重子及其反粒子.研究了中快度（|y| < 0.5）下，$Ξ^-$和$Ξ^+$重子在0.6 < $p_{\rm T}$ < 8.5 GeV/ $c$范围内，以及$Ω^-$和$Ω^+$在0.8 < $p_{\rm T}$ < 5 GeV/$c$范围内的横向动量（$p_{\rm T}$）分布.重子和反重子作为单独的粒子进行测量，我们发现，重子反重子的比例的两种粒子是一致的，在整个测量范围内的统一。目前大型强子对撞机数据的统计精度使我们能够测量$Ξ^-$（$Ξ^+$）和$Ω^-$（$Ω^+$）的平均值$p_{\rm T}$之间的差异。粒子产额、平均$p_{\rm T}$和中间$p_{\rm T}$范围内的光谱并没有被PYTHIA Perugia 2011调谐蒙特卡罗事件发生器很好地描述，该事件发生器已经被调谐以再现早期的LHC数据。$Ω^-$（$Ω^+$）的差异最大。这个PYTHIA调接近于$p_{\rm T}$ < 0.85 GeV/ $c$的$Ξ^-$和$Ξ^+$重子的$p_{\rm T}$谱，并描述了$p_{\rm T}$ > 6.0 GeV/ $c$的$Ξ^-$和$Ξ^+$谱。我们还通过比较相应的（$Ω^{-}+Ω^+)/(Ξ^-+Ξ^+)$）比值随横向质量的变化来说明实验数据和模型之间的差异。

英文摘要：

A measurement of the multi-strange $Ξ^-$ and $Ω^-$ baryons and their antiparticles by the ALICE experiment at the CERN Large Hadron Collider (LHC) is presented for inelastic proton-proton collisions at centre of mass energy of 7 TeV. The transverse momentum ($p_{\rm T}$) distributions were studied at mid-rapidity (|y| < 0.5) in the range of 0.6 < $p_{\rm T}$ < 8.5 GeV/$c$ for $Ξ^-$ and $Ξ^+$ baryons, and in the range of 0.8 < $p_{\rm T}$ < 5 GeV/$c$ for $Ω^-$ and $Ω^+$. Baryons and antibaryons were measured as separate particles and we find that the baryon to antibaryon ratio of both particle species is consistent with unity over the entire range of the measurement. The statistical precision of the current LHC data has allowed us to measure a difference between the mean $p_{\rm T}$ of $Ξ^-$ ($Ξ^+$) and $Ω^-$ ($Ω^+$). Particle yields, mean $p_{\rm T}$, and the spectra in the intermediate $p_{\rm T}$ range are not well described by the PYTHIA Perugia 2011 tune Monte Carlo event generator, which has been tuned to reproduce the early LHC data. The discrepancy is largest for $Ω^-$ ($Ω^+$). This PYTHIA tune approaches the $p_{\rm T}$ spectra of $Ξ^-$ and $Ξ^+$ baryons below $p_{\rm T}$ < 0.85 GeV/$c$ and describes the $Ξ^-$ and $Ξ^+$ spectra above $p_{\rm T}$ > 6.0 GeV/$c$. We also illustrate the difference between the experimental data and model by comparing the corresponding ratios of ($Ω^{-}+Ω^+)/(Ξ^-+Ξ^+)$ as a function of transverse mass.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

摘要：

英文摘要：

相关论文