119208348
ISGUR–WISE FUNCTION IN A QCD POTENTIAL MODEL WITH COULOMBIC POTENTIAL AS PERTURBATION
We study heavy light mesons in a QCD inspired quark model with the Cornell potential $-\frac{4\alpha_{S}}{3r}+br+c$. Here we consider the linear term br as the parent and $-\frac{4\alpha_{S}}{3r}+c$, i.e. the Coloumbic part as the perturbation. The linear parent leads to Airy function as the unperturbed wave function. We then use the Dalgarno method of perturbation theory to obtain the total wave function corrected up to first order with Coulombic piece as the perturbation. With these wave functions, we study the Isgur–Wise function and calculate its slope and curvature.
120396984
Free-field theory, fixed-point theory, and electron-positron annihilation into hadrons
The R problem of electron-positron physics is analyzed within the frameworks of a free-field theory (parton models) and a field theory with an infrared-stable fixed point. Present data do not rule out either of these models and hence they both can survive as alternatives to standard QCD in the R problem.
118509628
AN ANALYSIS OF THE ISGUR–WISE FUNCTION AND ITS DERIVATIVES WITHIN A HEAVY–LIGHT QCD QUARK MODEL
In determining the mesonic wave function from QCD inspired potential model, if the linear confinement term is taken as parent (with Coulombic term as perturbation), Airy's function appears in the resultant wave function — which is an infinite series. In the study of Isgur–Wise function (IWF) and its derivatives with such a wave function, the infinite upper limit of integration gives rise to divergence. In this paper, we have proposed some reasonable cutoff values for the upper limit of such integrations and studied the subsequent effect on the results. We have also studied the sensitivity of the order of polynomial approximation of the infinite Airy series in calculating the derivatives of IWF.
122709605
THE ISGUR–WISE FUNCTION IN AN IMPROVED QCD INSPIRED QUARK MODEL
We calculate the Isgur–Wise function of heavy light mesons and its derivatives — its slope and its curvature, in an improved version of our earlier QCD Inspired Quark Model with two-loop static potential.
120091736
An analysis of a quantum chromodynamic structure function
We obtain an approximate solution of Altarelli-Parisi equations yielding a sample of quantum chromodynamic structure function. The SLAC-MIT data are analysed with it. Possible effects of intrinsic charm and higher twist are also included. Agreement is found to be good forx⩾0.25.
119568734
Masses in structure functions
We derive an approximate formula for the quark mass in ξ-formalism. Using the QCD-based form of structure function, we analyse the SLAC-MIT data to estimate the experimentally allowed ranges of quark mass. The possible variation of our results with QCD cut-off parameter, gluon distribution, hard intrinsic charm component of the proton wavefunction and the higher twist effects are also discussed.
119329980
Compton Scattering on He-3
We present first calculations for Compton scattering on $^3$He. The objective of the calculation is an extraction of the neutron polarizabilities.
9428112
Investigating neutron polarizabilities through Compton scattering on 3He.
We examine manifestations of neutron electromagnetic polarizabilities in coherent Compton scattering from the helium-3 nucleus. We calculate gamma3He elastic scattering observables using chiral perturbation theory to next-to-leading order [O(e2Q)]. We find that the unpolarized differential cross section can be used to measure neutron electric and magnetic polarizabilities, while two double-polarization observables are sensitive to different linear combinations of the four neutron spin polarizabilities.
119348603
Predictions for polarized-beam and/or vector-polarized-target observables in elastic Compton scattering on the deuteron
Motivated by ongoing developments at High-Intensity Gamma Source (HI\ensuremath{\gamma}S) at Triangle Universities Nuclear Laboratory (TUNL) that include increased photon flux and the ability to circularly polarize photons, we calculate several beam-polarization and/or target-spin-dependent observables for elastic Compton scattering on the deuteron. This is done at energies of the order of the pion mass within the framework of heavy-baryon chiral perturbation theory. Our calculation is complete to $\mathcal{O}({Q}^{3})$ and at this order there are no free parameters. Consequently, the results reported here are predictions of the theory. We discuss paths that may lead to the extraction of neutron polarizabilities. We find that the photon/beam polarization asymmetry is not a good observable for the purpose of extracting ${\ensuremath{\alpha}}_{n}$ and ${\ensuremath{\beta}}_{n}$. However, one of the double polarization asymmetries, ${\ensuremath{\Sigma}}_{x}$, shows appreciable sensitivity to ${\ensuremath{\gamma}}_{1n}$ and could be instrumental in pinning down the neutron spin polarizabilities.