13,103 research outputs found
On Hermitian separability of the next-to-leading order BFKL kernel for the adjoint representation of the gauge group in the planar N = 4 SYM
We analyze a modification of the BFKL kernel for the adjoint representation
of the colour group in the maximally supersymmetric (N=4) Yang-Mills theory in
the limit of a large number of colours, related to the modification of the
eigenvalues of the kernel suggested by S. Bondarenko and A. Prygarin in order
to reach the Hermitian separability of the eigenvalues. We restore the modified
kernel in the momentum space. It turns out that the modification is related
only to the real part of the kernel and that the correction to the kernel can
not be presented by a single analytic function in the entire momentum region,
which contradicts the known properties of the kernel
UHE neutrinos: higher twists, scales, saturation
It is shown that in the ultra-high energy neutrino interactions the higher
twist corrections brought about by the non-conservation of the top-bottom
current dramatically change the longitudinal structure function, . To the
Double Leading Log Approximation simple and numerically accurate formulas for
and are derived.Comment: 5 pages, 1 figure, Talk given at Diffraction 2010, Otranto (Lecce),
Italy, September 10-15, 201
Discontinuites of BFKL amplitudes and the BDS ansatz
We perform an examination of discontinuities of multiple production
amplitudes, which are required for further development of the BFKL approach. It
turns out that the discontinuities of 2 2 + n amplitudes obtained in the
BFKL approach contradict to the BDS ansatz for amplitudes with maximal helicity
violation in N = 4 supersymmetric Yang-Mills theory with large number of
colours starting with n = 2. Explicit expressions for the discontinuities of
the 2 3 and 2 4 amplitudes in the invariant mass of pairs of
produced gluons are obtained in the planar N=4 SYM in the next-to-leading
logarithmic approximation. These expressions can be used for checking the
conjectured duality between the light-like Wilson loops and the MHV amplitudes.Comment: 26 page
Non-forward BFKL Pomeron at next-to-leading order
The kernel of the BFKL equation for non-zero momentum transfer is found at
next-to-leading order. It is presented in various forms depending on the
regularization of the infrared singularities in "virtual" and "real" parts of
the kernel. The infrared safety of the total kernel is demonstrated and a form
free from the singularities is suggested.Comment: 8 page
Current non-conservation effects in DIS diffraction
In the neutrino DIS diffraction the charged current non-conservation gives
rise to sizable corrections to the longitudinal structure function, .
These corrections is a higher twist effect enhanced at small- by the rapidly
growing gluon density. The phenomenon manifests itself in abundant production
of charm and strangeness by longitudinally polarized W bosons of moderate
virtualities Q^2\lsim m_c^2.Comment: Prepared for the Int. Workshop on Diffraction in High-Energy Physics,
Diffraction 2008, La Londe-les-Maures, France, Sept. 9-14, 200
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