84 research outputs found
Polarized Deep Inelastic Diffractive Scattering near the Light Cone
Polarized inclusive deep-inelastic scattering is formulated in the light cone
expansion. The QCD evolution of the leading twist distribution functions is
derived. It is shown that the twist--2 contribution to the structure functions
g_2^{D(3)} is obtained via g_1^{D(3)} by a Wandzura--Wilczek relation.Comment: 4 pages LATEX, 2 subsidiary files, contribution to QCD-N'02, Ferrara
and DIS 2002, Craco
Thermodynamics of the Casimir effect
A complete thermodynamic treatment of the Casimir effect is presented.
Explicit expressions for the free and the internal energy, the entropy and the
pressure are discussed. As an example we consider the Casimir effect with
different temperatures between the plates () resp. outside of them ().
For the pressure of heat radiation can eventually compensate the Casimir
force and the total pressure can vanish. We consider both an isothermal and an
adiabatic treatment of the interior region. The equilibrium point (vanishing
pressure) turns out instable in the isothermal case. In the adiabatic situation
we have both an instable and a stable equilibrium point, if is
sufficiently small. Quantitative aspects are briefly discussed.Comment: 12 pages, 3 EPS-figure
On the Scaling Violations of Diffractive Structure Functions: Operator Approach
A quantum field theoretic treatment of inclusive deep-inelastic diffractive
scattering is given. The process can be described in the general framework of
non-forward scattering processes using the light-cone expansion in the
generalized Bjorken region. Evolution equations of the diffractive hadronic
matrix elements are derived at the level of the twist-2 contributions and are
compared to those of inclusive deep-inelastic forward scattering (DIS). The
diffractive parton densities are obtained as projections of two-variable parton
distributions. We also comment on the higher twist contributions in the
light-cone expansion.Comment: 12 pages LATEX, 2 style file
Leading Twist Amplitudes for Exclusive Neutrino Interactions in the Deeply Virtual Limit
Neutrino scattering on nucleons in the regime of deeply virtual kinematics is
studied both in the charged and the neutral electroweak sectors using a
formalism developed by Blumlein, Robaschik, Geyer and Collaborators for the
analysis of the Virtual Compton amplitude in the generalized Bjorken region. We
discuss the structure of the leading twist amplitudes of the process.Comment: 14 pages, 1 fig revised final version to appear in Phys. Rev.
Construction of nonlocal light-cone operators with definite twist
A systematic procedure is introduced to uniquely decompose nonlocal
LC-operators into harmonic operators of well defined geometric twist. The
method will be demonstrated for (pseudo)scalar, (axial) vector and skew tensor
bilocal quark light-ray operatorsComment: 4 pages, AMSTeX, Contribution to 7th Int. Workshop on Deep Inelastic
Scatterin and QCD, Zeuthen, April 1999 change of formulas 25 and 2
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