论文标题
$γ^*γ$和$γ^* p $ scatting in ihqcd
$γ^* γ$ and $γ^* p$ scattering in IHQCD
论文作者
论文摘要
我们使用质子结构函数的测量$ f_2（x，q^2）$和$ f_l（x，q^2）$进行关节拟合，该功能的光子结构函数$ f_2^γ（x，q^2）$以及总交叉点的$ f _2^γ\ feft（γp\ rightarrow x \ rightarrow x \ right）$和$ nir $ n $ $ niws $ n $ nirriand（unirlaw）$ f。数据是从包括HERA和LEP在内的多个来源收集的。所考虑的运动范围宽，带有光子虚拟$ q^2 \ leq400 \，{\ rm gev}^2 $，bjorken varible $ x <0.01 $和$ \ sqrt {s}> 4 \，{\ rm gev} $。这是通过考虑一个$ u \左（1 \右）$ vector量规场最小化的左耦合到Reved Holographic QCD中的Graviton Regge轨迹。我们找到了与$ f_2^γ$和$σ\ left（γγ\ rightarrow x \ right）$的联合拟合数据的良好共识，其中$χ_{d.o.f。}^2 = 1.07 $。对于$ f_2 $，$ f_l $和$σ\ left（γp\ rightarrow x \ right）$的联合拟合，我们找到$χ_{d.o.f。}^2 = 1.40 $。所有可观察到两个过程的联合拟合$γ^*γ$和$γ^* p $都给出了$χ_{d.o.f。}^2 = 1.38 $。 $ u \ lest（1 \右）$矢量量规场的重力耦合和带有重力型轨迹的质子的质子作为拟合程序的输出给出。在NLO QCD上有效的结构函数之间的近似关系用于估计质子内Gluon的Parton分布函数。
We perform joint fits using measurements of the proton structure functions $F_2(x,Q^2)$ and $F_L(x,Q^2)$, of the photon structure function $F_2^γ(x,Q^2)$ and of the total cross-sections $σ\left( γp \rightarrow X\right)$ and $σ\left( γγ\rightarrow X\right)$. The data is gathered from several sources including HERA and LEP. The kinematical range considered is wide with a photon virtuality $Q^2 \leq400 \, {\rm GeV}^2$, Bjorken variable $x<0.01$ and $\sqrt{s} > 4 \, {\rm GeV}$. This is done by considering a $U\left(1\right)$ vector gauge field minimally coupled to the graviton Regge trajectory in improved holographic QCD. We find good agreement with the data for a joint fit of $F_2^γ$ and $σ\left(γγ\rightarrow X\right)$ with a $χ_{d.o.f.}^2 = 1.07$. For a joint fit of $F_2$, $F_L$ and $σ\left( γp \rightarrow X\right)$ we find $χ_{d.o.f.}^2 = 1.40$. A joint fit of all observables for both processes $γ^* γ$ and $γ^* p$ gives a $χ_{d.o.f.}^2 = 1.38$. The gravitational couplings of the $U\left(1\right)$ vector gauge field and of the proton with the Reggeons of the graviton Regge trajectory are given as an output of the fitting procedure. An approximate relation between the structure functions, valid at NLO QCD, is used to estimate the parton distribution function of the gluon inside the proton.
