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Transverse momentum dependent (TMD) parton distributions, also referred to as unintegrated parton distribution functions (UPDFs), are produced via the Kimber-Martin-Ryskin (KMR) prescription. The GJR08 set of parton distribution functions (PDFs) which are based on the valence-like distributions is used, at the leading order (LO) and the next-to-leading order (NLO) approximations, as inputs of the KMR formalism. The general and the relative behaviors of the generated TMD PDFs at LO and NLO and their ratios in a wide range of the transverse momentum values, i.e. , , and are investigated. It is shown that the properties of the parent valence-like PDFs are imprinted on the daughter TMD PDFs. Imposing the angular ordering constraint (AOC) leads to the dynamical variable limits on the integrals which in turn increase the contributions from the lower scales at lower . The results are compared with our previous studies based on the MSTW2008 input PDFs and it is shown that the present calculation gives flatter TMD PDFs. Finally, a comparison of longitudinal structure function is made by using the produced TMD PDFs and those that were generated through the MSTW2008-LO PDF from our previous work and the corresponding data from H1 and ZEUS collaborations and a reasonable agreement is found. [ABSTRACT FROM AUTHOR]

The quark exchange formalism is formulated to calculate the quark momentum distribution in the iso-scalar Lithium nucleus. Then by boosting the nucleus to an infinite momentum frame, the Lithium structure function is evaluated at different nucleon "sizes", i.e., b = 0.7, 0.8, 0.9 and 1 fm and the Bjorken scale (x) values. It is shown that the Lithium structure function becomes narrower, and it is pushed to the smaller x values, as the nucleon size is increased. Similar to our previous works for three nucleon systems, the Lithium nucleus European muon collaboration (EMC) ratio decreases, as we increase the x and b values and it shows larger effect, with respect to the free nucleon and three nucleons iso-scalar nucleus. On the other hand, present calculation of the EMC ratio for Lithium nucleus shows a good agreement with the corresponding NMC data, which is available for 1.4 × 10-4 ≤ x ≤ 0.65. Since the atomic number is still small (A = 6), in this work as usual, we ignore the possibility of simultaneous exchange of quarks between more than two nucleons, which can be important as one moves to the heavy nuclei. Although, according to Hen et al., in the neutron rich nuclei the protons have a greater probability than neutrons to have momentum greater than the Fermi momentum, the three-body contribution may be suppressed. [ABSTRACT FROM AUTHOR]

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 Fp2(x,Q2), 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 3He and 3H 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. [ABSTRACT FROM AUTHOR]

In this work, the response functions (RFs) of the 4He, 16O and 40Ca nuclei are calculated in the harmonic oscillator shell model (HOSM) and the impulse approximation (IA). First, the one-body momentum distribution and the one-body spectral functions for these nuclei are written in the HOSM configuration. Then, their RFs are calculated, in the two frameworks, namely the spectral and the momentum distribution functions, within the IA. Unlike our previous work, no further assumption is made to reduce the analytical complications. For each nucleus, it is shown that the (RF) evaluated using the corresponding spectral function has a sizable shift, with respect to the one calculated in terms of the momentum distribution function. It is concluded that for the heavier nuclei, this shift increases and reaches nearly to a constant value (approximately 62 MeV), i.e., similar to that of nuclear matter. It is discussed that in the nuclei with the few nucleons, the above shift can approximately be ignored. This result reduces the theoretical complication for the explanation of the ongoing deep inelastic scattering (DIS) experiments of ³H or ³H nucleus target in the Jefferson Laboratory. On the other hand, it is observed that in the heavier nuclei, the RF heights (width) decrease (increase), i.e., the comparison between the theoretical and the experimental electron nucleus scattering cross-section is more sensible for heavy nuclei rather than the light ones. [ABSTRACT FROM AUTHOR]

The ambiguities proposed by Benhar et al., about the the different implementation of the impulse approximation for calculating the response function of many-fermion systems, are investigated theoretically in the frame work of simple harmonic oscillator shell model for the double closed shell nuclei, e.g. 4He, 16O and 40Ca nuclei. For each nucleus as a finite system, we evaluate the response function by using its definition in terms of the one-body spectral function and the one-body momentum distribution. It is demonstrated analytically, that there exists a sizable shift between the two schemes for each nucleus, which increases as we switch to the heavier nuclei. So one can conclude that for the nuclei with atomic number less than 4, such as 2H, 3H or 3He, it is good approximation to ignore this discrepancy. This conclusion is important for theoretical explanation of the ongoing deep inelastic scattering (DIS) experiments of 3H or 3H in the Jefferson Laboratory. However present calculation confirms the work of Modarres and Younesizadeh (2010), in which they have shown that, the above shift can be removed by imposing the impulse approximation in the same footing in the many-fermion wave-function. [ABSTRACT FROM AUTHOR]

The ground state properties of light closed shell nuclei, i.e. 4He, 12C, 16O, 28Si, 32S, 40Ca and 56Ni are studied by using the channel-dependent effective two-body interactions (CDEI's). The CDEI's are generated through the lowest-order constrained variational (LOCV) calculation for asymmetric nuclear matter with the charge-dependent Av18 bare nucleon-nucleon potential. The work is performed on the harmonic oscillator basis, and the local density approximation is applied to create the relative and the center of mass dependent effective two-body potential. Unlike nuclear matter, and similar to our previous calculations with the Reid68 interaction, while the Av18 potential under binds above nuclei up Jmax = 2 channel, it gives ground state binding energies closer to the experimental data with respect to the Δ- Reid68 and the Reid68 potentials. There are not much difference between the results of Av18 interaction with Jmax = 5, and those of Reid68Day potential which has been define up to Jmax = 5. The different CDEI's up to Jmax = 5 are discussed and the results of our calculations are compared with the other theoretical approaches and experimental data. Finally, it is shown that the contributions of higher partial waves (J>2) are not very important and the two-body kinetic energy in J = 1 channel is roughly twice as that of J = 0 which is not the case for the two-body potential energy. [ABSTRACT FROM AUTHOR]

We calculate the thermodynamic properties of strange quark matter by using the density and temperature dependent particle mass model of Wen et al. For the interaction Hamiltonian we use the one gluon exchange interaction obtained from the Fermi liquid picture. We let the QCD coupling (αc) be constant or vary with density and temperature. A new set of mass scalings for quarks is evaluated from the present interaction, which can be used with thermodynamic formulas derived by Wen et al. Similar to β-stable matter, no stability is found in strange quark matter. Finally, it is shown that the present equation of state of strange quark matter becomes harder with respect to that obtained using the string model, specially with non-constant QCD coupling. [ABSTRACT FROM AUTHOR]

We investigate the possible angular momentum, l, dependence of the ground state energy of normal liquid 3He. The method of lowest order constrained variational (LOCV) which includes the three-body cluster energy and normalization constraint (LOCVE) is used with angular momentum dependent two-body correlation functions. A functional minimization is performed with respect to each l-channel correlation function. It is shown that this dependence increases the binding energy of liquid 3He by 8% with respect to calculations without angular momentum dependent correlation functions. The l=0 state has completely different behavior with respect to other l-channels. It is also found that the main contribution from potential energy comes from the l=1 state (p-waves) and the effect of l≥11 is less than about 0.1%. The effective interactions and two-body correlations in different channels are being discussed. Finally we conclude that this l-dependence can be verified experimentally by looking into the magnetization properties of liquid helium 3 and interatomic potentials. [ABSTRACT FROM AUTHOR]

The Coulomb sum rule (CSR) and structure factor are calculated for inelastic electron scattering from nuclear matter at zero and finite temperature in the nonrelativistic limit. The effect of short-range correlation (SRC) is presented by using lowest order constrained variational (LOCV) method and the Argonne Av18 and Δ-Reid soft-core potentials. The effects of different potentials as well as temperature are investigated. It is found that the nonrelativistic version of Bjorken scaling approximately sets in at the momentum transfer of about 1.1 to 1.2 GeV/c and the increase of temperature makes it to decrease. While different potentials do not significantly change CSR, the SRC improves the Coulomb sum rule and we get reasonably close results to both experimental data and others theoretical predictions. [ABSTRACT FROM AUTHOR]