论文标题
$ f_ {0}（980）$ MESON在LHC上的生产：颜色蒸发与颜色 - 单词Gluon-Gluon Fusion
Production of $f_{0}(980)$ meson at the LHC: Color evaporation versus color-singlet gluon-gluon fusion
论文作者
论文摘要
$ f_ {0}（980）在高能的生产尚不清楚。我们研究了$ k_t $ factorization方法中包容性标量介子产生的两种不同潜在机制：色彩单词Gluon-Gluon融合和颜色蒸发模型。 $γ^*γ^* \ to f_0（980）$ form source可以从$ f_0（980）$辐射衰减宽度限制。 $ g^* g^* \ to f_0（980）$形式是通过更换$α_ {\ rm {em}} $电磁耦合常数而获得$α_ {\ rm {s}} $强的搭配常数和适当的色素因素来获得的。两个耦合的形态因素是通过标量Quarkonia的最新结果激励的函数进行了参数化的。差分横截面以现代未集成的Gluon分布的$ k_t $ factorization方法计算。与Quarkonia不同，似乎很难描述由颜色Singlet Gluon-Gluon融合机制专门描述$ f_0（980）$的初步爱丽丝数据。在这种情况下，考虑了$ f_0（980）$的风味结构的两种不同方案。我们还考虑了有时用于Quarkonium生产的现象学色彩蒸发模型（CEM）中与软gluon发射相关的夸克式瓦克式融合机制。在这里，我们使用CEM的$ k_t $ -Factorization版本来包括高阶贡献。此外，为了进行比较，我们还考虑使用$ q \ bar {q} q $和$ q \ bar {q} g $ color octet partit partononic最终状态。两种方法都会带来类似的结果。但是，需要很大的概率来描述初步的爱丽丝数据。还讨论了Pomeron-Pomeron融合机制，并量化了结果。
The production of the $f_{0}(980)$ meson at high energies is not well understood. We investigate two different potential mechanisms for inclusive scalar meson production in the $k_t$-factorization approach: color-singlet gluon-gluon fusion and color evaporation model. The $γ^* γ^* \to f_0(980)$ form factor(s) can be constraint from the $f_0(980)$ radiative decay width. The $g^* g^* \to f_0(980)$ form factors are obtained by a replacement of $α_{\rm{em}}$ electromagnetic coupling constant by $α_{\rm{s}}$ strong coupling constant and appropriate color factors. The form factors for the two couplings are parametrized with a function motivated by recent results for scalar quarkonia. The differential cross sections are calculated in the $k_t$-factorization approach with modern unintegrated gluon distributions. Unlike for quarkonia it seems rather difficult to describe a preliminary ALICE data for inclusive production of $f_0(980)$ exclusively by the color singlet gluon-gluon fusion mechanism. Two different scenarios for flavor structure of $f_0(980)$ are considered in this context. We consider also mechanism of fusion of quark-antiquark associated with soft gluon emission in a phenomenological color evaporation model (CEM) used sometimes for quarkonium production. Here we use $k_t$-factorization version of CEM to include higher-order contributions. In addition, for comparison we consider also NLO collinear approach with $q \bar{q} q$ and $q \bar{q} g$ color octet partonic final states. Both approaches lead to a similar result. However, very large probabilities are required to describe the preliminary ALICE data. The pomeron-pomeron fusion mechanism is also discussed and results are quantified.
