A systematic study on the impact of widely-used nuclear-modified parton distribution function(nPDF)parameterizations on the production of direct photons and charged hadrons is performed by employing a next-toleading o...
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A systematic study on the impact of widely-used nuclear-modified parton distribution function(nPDF)parameterizations on the production of direct photons and charged hadrons is performed by employing a next-toleading order Monte Carlo event generator JETPHOX in hadronic collisions at LHC *** nuclear modification factors of photon and charged hadron productions are studied in three types of collision systems,i.e.,small(p+p and p+Pb),medium(O+O),and large(Pb+Pb),in a wide rapidity *** results illustrate that the direct photon production process is a sensitive probe to decipher the difference of the nPDF parameterization implementations,which provides new insights for the experimental measurements to refine the nuclear modifications of the parton *** provide a benchmark for searching for quark gluon plasma in the upcoming small system measurements at LHC energies,we carry out detailed studies on the cold nuclear matter effect in(O+O)*** outcomes show that the cold nuclear matter effects are negligible for the charged hadron production in(O+O)collisions,which can be used as a baseline to subtract the initial state contribution.
We use the refined hot spot model to study the valence quark shape of the proton with the deeply virtual Compton scattering at high energies in the color glass condensate *** investigate the individual valence quark s...
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We use the refined hot spot model to study the valence quark shape of the proton with the deeply virtual Compton scattering at high energies in the color glass condensate *** investigate the individual valence quark shape,a novel treatment of the valence quark width is *** calculate the cross-sections for coherent and incoherent deeply virtual Compton scattering using,for the first time,different widths(Bu and Bd)for the profile density distributions of the up and down quarks instead of using the same width as in the *** find that the cross-sections calculated with Bu≥Bd at each collision energy are consistent with each other,which is in agreement with theoretical expectations,whereas those computed with Bu
在色玻璃凝聚框架下,将Sudakov效应运用到矢量介子产生中,计算了衍射遍举和衍射离解两种过程中轻(φ)和重(J/ψ)介子产生的微分截面和总截面。首先,利用数值方法求解微分积分形式的领头阶偶极子演化方程和Sudakov抑制的次领头阶偶极子演化方程,得到相应的偶极子散射振幅,研究发现Sudakov抑制的次领头阶偶极子散射振幅小于同一快度下领头阶的偶极子散射振幅,随着快度增加两者之间的差距越来越大,由此表明Sudakov效应压低了偶极子散射振幅的演化速度。其次,将这些偶极子散射振幅应用到衍射矢量介子产生模型中,描述HERA(hadron electron ring accelerator)能区φ和J/ψ介子产生相关实验数据,得到Sudakov抑制时的χ^(2)/N_(p)=1.26远小于领头阶时的χ^(2)/N_(p)=1.87,由此Sudakov效应提高了模型的精度,使得修正后的偶极子散射振幅能较好地描述相关数据,表明了Sudakov效应在矢量介子产生中起着重要的作用。
To obtain a reasonable description of the hadron production at the LHC energies,the impact parameter dependent saturation model is modified by inclusion of an anomalous dimensionγ,which controls the slope of the scat...
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To obtain a reasonable description of the hadron production at the LHC energies,the impact parameter dependent saturation model is modified by inclusion of an anomalous dimensionγ,which controls the slope of the scattering amplitude in the transition from the dilute region to the saturation *** calculate the transverse momentum distribution and nuclear modification factor of theπ^(0)and charged hadrons with the improved model,and the results are consistent with measurements performed at the ***,we use the original impact parameter dependent model to study the aforementioned measurements performed at the LHC by adjusting its *** find that the improved model is more consistent with the experimental data than the original one,as the anomalous dimension plays a significant role in the suppression of the evolution of the scattering amplitude.
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