Nuclear dependence of structure functions in coordinate space

Using the high-energy Operator Product Expansion of the T-product of two electromagnetic currents, we calculate the Photon Impact Factor for Deep Inelastic Scattering at small value of the Bjorken variable x B at the next-to-leading order (NLO) accuracy in αs. We provide for the first time an analytic expression in coordinate space and in Mellin space of the NLO impact factor for the forward unpolarized structure functions.

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FLUID HELIUM-4 IN THERMAL EQUILIBRIUM

International Journal of Modern Physics B ◽

10.1142/s0217979209063286 ◽

2009 ◽

Vol 23 (20n21) ◽

pp. 4096-4108 ◽

Cited By ~ 4

Author(s):

K. A. GERNOTH ◽

M. L. RISTIG

Keyword(s):

Correlation Functions ◽

Formal Analysis ◽

Quantum Correlations ◽

Structure Functions ◽

Coordinate Space ◽

Spatial Correlations ◽

Energy Distributions ◽

Helium 4 ◽

Particle Exchange ◽

Interparticle Repulsion

The microscopic quantum structure of fluid 4 He may be clearly revealed by a proper decomposition of its spatial correlations into quantum statistical components and direct quantum correlations. This decomposition permits to elucidate the competition between the short-ranged statistical (or particle exchange) correlations and the quantum correlations brought about by the existing strong interparticle repulsion at short relative particle-particle distances. The appropriate method of choice is provided by correlated density-matrix (CDM) theory. It does not only permit a detailed formal analysis of this competition but also allows for a quantitative numerical computation of correlation functions, structure functions, and momentum and energy distributions. The theoretical CDM results for 4 He are, so far as possible, compared with results from path-integral Monte Carlo (PIMC) calculations and with available experimental results. Reported are CDM results on relevant structure functions, correlation functions in coordinate space, kinetic energy distributions, and gross quantitities such as the exchange energy for fluid 4 He . The calculations are performed for normal helium at various temperatures in the range T BE = 2.17 K ≤ T < 14 K .

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THE ROLE OF FERMI MOTION ON THE STRUCTURE FUNCTIONS OF 3He AND 3H NUCLEI IN THE QUARK EXCHANGE FRAMEWORK

International Journal of Modern Physics E ◽

10.1142/s0218301313500377 ◽

2013 ◽

Vol 22 (06) ◽

pp. 1350037 ◽

Cited By ~ 5

Author(s):

M. MODARRES ◽

M. RASTI

Keyword(s):

Experimental Data ◽

Wave Function ◽

Three Dimensional ◽

Structure Functions ◽

Exchange Model ◽

Coordinate Space ◽

Nuclear Wave Function ◽

Fermi Motion ◽

Nucleon Wave Function

The quark exchange model and the full three-nucleon wave function in the configuration space are used to evaluate the role of Fermi motion on the structure functions (SFs) of helium-3 and tritium nuclei. The three-nucleon wave function is obtained from the solution of the Faddeev equations with the Malfliet–Tjon-type potential, by using the three-dimensional approach as a function of the magnitudes of the Jacobi momenta vectors and the angle between them. In this calculation, the initial valence quarks inputs are taken from the GRV's (Glück, Reya and Vogt) fitting procedure and the next-to-leading order (NLO) QCD calculation on [Formula: see text], which give a very good fit to the available experimental data in the (x, Q2)-plane. The role of Fermi motion on the EMC ratio of the SFs of 3 He and 3 H nuclei are analyzed through the NLO expansion of the nuclear wave function in the coordinate space. A good agreement between the calculated EMC ratios, the corresponding experimental data and the theoretical results is found. Finally, the ratios of the SFs of the neutron to the proton (with the isospin symmetry assumption) with and without the Fermi motion effect, are also calculated, and they are compared with the available experimental data. Our results show that the roles of the Fermi motion in the framework of the quark exchange model for the calculations of the nuclear SFs are important.

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