The Role of Higher Twist in Determining Polarized Parton Densities from DIS data

Different methods to extract the polarized parton densities from the world polarized DIS data are considered. The higher twist corrections $h^N(x)/Q^2$ to the spin dependent proton and neutron $g_1$ structure functions are found to be non-negligible and important in the QCD analysis of the present experimental data. Their role in determining the polarized parton densities in the framework of the different approaches is discussed.Comment: To appear in the Proceedings of the Spin2004 Symposium, Trieste, 11-16 Oct 200

Target Mass Effects in Polarized Deep Inelastic Scattering

The target mass effects in polarized DIS have been studied. It was demonstrated that taking into account the first order target mass corrections to g1 a very good approximation of the exact formula is achieved. It was also shown that their magnitude in the preasymptotic DIS region is small except for x > 0.65, where their large effect is partially suppressed by the large values of $Q^2$ due to the cut $W^2 > 4 GeV^2$. The difference between the size of the target mass and higher twist corrections is illustrated.Comment: 8 pages, LaTeX, 5 figures, typo in Eq. 3 corrected, comment added, to appear in Mod. Phys. Lett.

Some Remarks on Methods of QCD Analysis of Polarized DIS Data

The results on polarized parton densities (PDFs) obtained using different methods of QCD analysis of the present polarized DIS data are discussed. Their dependence on the method used in the analysis, accounting or not for the kinematic and dynamic 1/Q^2 corrections to spin structure function g_1, is demonstrated. It is pointed out that the precise data in the preasymptotic region require a more careful matching of the QCD predictions to the data in this region in order to determine the polarized PDFs correctly.Comment: 14 pages, 8 figure

Two-particle multiplets splitting as a guideline in nucleon pairing estimations

The ground state multiplet structure for nuclei over the wide range of mass number $A$ was calculated in $\delta$-approximation and different mass relations for pairing energy was analysed in this work. Correlation between the calculated multiplet structure and experimental data offer a guideline in deciding between mass relations for nucleon pairing.Comment: 6 pages, 2 fig., Proceedings of Intern. Session-Conference of the Section of Nuclear Physics of PSD RAS (April 12 - 15, 2016, JINR Dubna), to be published in Journal Physics of Elementary Particles and Atomic Nuclei (PEPAN

Semiclassical correlators of three states with large S^5 charges in string theory in AdS_5 x S^5

We consider semiclassical computation of 3-point correlation functions of (BPS or non-BPS) string states represented by vertex operators carrying large charges in S5. We argue that the AdS5 part of the construction of relevant semiclassical solution involves the two basic ingredients: (i) configuration of three glued geodesics in AdS2 suggested by Klose and McLoughlin in arXiv:1106.0495 and (ii) a particular Schwarz-Christoffel map of the 3-geodesic solution in cylindrical (tau, sigma) domain into the complex plane with three marked points. This map is constructed using the expression for the AdS2 string stress tensor which is uniquely determined by the 3 scaling dimensions as noted by Janik and Wereszczynski in arXiv:1109.6262 (our solution, however, is different from theirs). We also find the S5 part of the solution and thus the full expression for the semiclassical part of the 3-point correlator for several examples: extremal and non-extremal correlators of BPS states and a particular correlator of "small" circular spinning strings in S3 part of S5. We demonstrate that for the BPS correlators the results agree with the large charge limit of the corresponding supergravity and free gauge theory expressions.Comment: 43 pages, 4 figures; v2: minor corrections; v3: comments added at the end of section 3 and in section 5; v4: minor corrections; v5: discussion in subsection 3.3 correcte