论文标题
使用有关包容性锥子和KAON生产的数据在不固定的$ pp $碰撞中的数据和KAON生产的数据测试片段化函数的参数化。
Tests of the parametrizations of Fragmentation Functions using data on inclusive pion and kaon production in unpolarized $pp$ collisions from the STAR collaboration and at the NICA project
论文作者
论文摘要
The goal of this study is to check which, if any, of the published versions of the pion and kaon fragmentation functions is compatible with the STAR data on semi-inclusive pion and kaon production in proton-proton collisions, and on the basis of this analysis to make reliable predictions for the $p_T$ spectra of the pions and kaons in inclusive pion and kaon production at the future NICA proton-proton collider.使用经过良好测试的CTEQ6 PARTON分布以扰动量子染色体动力学（PQCD）的近代领先顺序（NLO）进行计算。我们考虑以下PION和KAON碎片函数（FFS）-DSEHS-14，DSEHS-17，LSS-15，HKNS-07和AKK-08。我们的分析表明，在实验错误中，所有测试的碎片函数集为C.M.能量$ \ sqrt {s} = 200 \，{\ rm gev} $，最好的是pions的lss-15和dsehs-14，而kaons则是dsehs-17。从LO和NLO结果的比较可以很明显，后者拟合的数据要好得多，特别是在小$ P_T $的区域。 NLO横截面的比例也小-Q^2 $依赖性，其中$ p_t/2 \ leqslant q \ leqslant 2p_t $，而不是lo。为了对NICA能量进行预测，我们将NLO PQCD的结果与现有的实验性BES Star数据进行比较，在最外围的AU+AU碰撞中，在可以忽略核效应的最外围Au+Au碰撞中，将NLO PQCD的结果与现有的实验性BES Star数据进行了比较。像在NICA一样，较低能量尺度的比较表明，纯PQCD方法是不足的，这表明还需要考虑到初始状态软云辐射的高阶效应。尽管如此，这些有关$π^+$，$ k^+$的$ p_t $ speptra上的数据以及比率$π^ - /π^+$和$ k^ - /k^ - /k^ - /k^+$似乎是喜欢LSS-15和DSEHS-14 ffs pions for Pions for Pions for Pions for Kaons for Kaons for Kaons for Kaons for Kaons for Kaons for Kaons for Kaons for Kaons for Kaons in Energy Stape $ \ \ sq sq sq sq sq rt = sq sq sq sq rt GEV} $。
The goal of this study is to check which, if any, of the published versions of the pion and kaon fragmentation functions is compatible with the STAR data on semi-inclusive pion and kaon production in proton-proton collisions, and on the basis of this analysis to make reliable predictions for the $p_T$ spectra of the pions and kaons in inclusive pion and kaon production at the future NICA proton-proton collider. The calculations are carried out in next-to-leading order (NLO) of perturbative quantum chromodynamics (pQCD), using the well tested CTEQ6 parton distributions. We consider the following pion and kaon fragmentation functions (FFs) -- DSEHS-14, DSEHS-17, LSS-15, HKNS-07 and AKK-08. Our analysis shows that within the experimental errors all tested sets of fragmentation functions provide a good fit to STAR data at the c.m. energy $ \sqrt{S} = 200\, {\rm GeV} $, and the best ones are both LSS-15 and DSEHS-14 for pions and DSEHS-17 for kaons. From comparison of the LO and NLO results it is clear that the latter fit data much better, specially in the region of small $p_T$. The NLO cross sections are also less scale-$Q^2$ dependent, where $p_T/2\leqslant Q \leqslant 2p_T$, than the LO ones. In order to make predictions for NICA energies, we compare the NLO pQCD results with the existing experimental BES STAR data on semi-inclusive hadron production in the most peripheral Au+Au collisions where the nuclear effects can be neglected. The comparison for lower energy scales, like at NICA, shows that a purely pQCD approach is inadequate and suggests the necessity to take into account also higher-order effects of initial-state soft-gluon radiation. Nevertheless, these data on the $p_T$ spectra of $π^+$, $K^+$ and also the ratios $π^-/π^+$ and $K^-/K^+$ seem favour LSS-15 and DSEHS-14 FFs for pions and DSEHS-17 for kaons, similarly as at the energy scale $ \sqrt{S} = 200\, {\rm GeV} $.
