113 citations · 559 across the 30 of their papers we have counts for
20 papers · 1 filter
Spontaneously Broken Chiral Symmetry and Hard QCD Phenomena
M. J. Amarian, V. M. Braun, S. J. Brodsky +28
These are the mini-proceedings of the workshop ``Spontaneously Broken Chiral Symmetry and Hard QCD Phenomena" held at the Physikzentrum Bad Honnef from July 15 to 19, 2002. Every a…
Twist-4 photon helicity-flip amplitude in DVCS on a nucleon in the Wandzura-Wilczek approximation
N. Kivel, L. Mankiewicz
We computed twist-4 part of the photon spin-flip amplitude in deeply virtual Compton scattering on a nucleon in the Wandzura-Wilczek approximation. We found a factorizable contribu…
Twist-3 contribution to the amplitude in the Wandzura-Wilczek approximation
N. Kivel, L. Mankiewicz
We have calculated the Wandzura-Wilczek contribution to the twist-3 part of amplitude. It describes interaction of the longitudinally polarized virtual photon with the…
Power corrections to the process in the Light-Cone Sum Rules approach
N. Kivel, L. Mankiewicz
We applied QCD Light Cone Sum Rules to estimate power corrections to the helicity-conserving amplitude in the process . We found that above GeV power c…
Exclusive meson production at COMPASS
Josef Pochodzalla, Lech Mankiewicz, Murray Moinester +3
We explore the feasibility to study exclusive meson production (EMP) in hard muon-proton scattering at the COMPASS experiment. These measurements constrain the off-forward parton d…
NLO corrections and contribution of a tensor gluon operator to the process
N. Kivel, L. Mankiewicz, M. V. Polyakov
We have calculated the NLO corrections for the leading twist amplitude of the reaction at large virtuality of the photon and at . With a simple model for th…
Conformal string operators and evolution of skewed parton distributions
N. Kivel, L. Mankiewicz
We have investigated skewed parton distributions in coordinate space. We found that their evolution can be described in a simple manner in terms of non-local, conformal operators i…
Higher-twist contributions in exclusive processes
M. Vänttinen, L. Mankiewicz, E. Stein
Using the renormalon technique, we estimate higher-twist contributions in deeply virtual Compton scattering and in hard exclusive leptoproduction.
Nuclear Quark and Gluon Distributions in Coordinate Space
M. Vänttinen, G. Piller, L. Mankiewicz +2
In coordinate space, quark and gluon distributions of the nucleon are defined as correlation functions involving two field operators separated by a light-cone distance .…
Hard exclusive leptoproduction on polarized targets
M. Vänttinen, L. Mankiewicz
We consider the exclusive production of mesons in polarized virtual-photon--proton collisions. We derive helicity amplitudes for the dominant subprocess and…
Hard Exclusive Meson Production and Nonforward Parton Distributions
L. Mankiewicz, G. Piller, T. Weigl
We present an analysis of twist-2, leading order QCD amplitudes for hard exclusive leptoproduction of mesons in terms of double/nonforward parton distribution functions. After revi…
Analytic Approximation to the GLAP evolution of in the small- region
L. Mankiewicz, A. Saalfeld, T. Weigl
We propose a systematic approximation scheme for solving GLAP evolution equations at small Bjorken-. The approximate solutions interpolate smoothly between hard (singular as $x^…
Sphinx v1.1 - Monte Carlo Program for Polarized Nucleon-Nucleon Collisions (update)
Stefan Güllenstern, Oliver Martin, Pawel Gornicki +2
We present the updated long write-up for version 1.1 of the SPHINX Monte Carlo. The program can be used to simulate polarized nucleon - nucleon collisions at high energies. Spins o…
Phenomenology of IR-renormalons in inclusive processes
M. Maul, E. Stein, A. Schäfer +1
We have compared the existing experimental data on the leading power corrections to the structure functions , and with the IR-renormalon model…
Combining Lattice QCD Results with Regge Phenomenology in a Description of Quark Distribution Functions
L. Mankiewicz, T. Weigl
The most striking feature of quark distribution functions transformed to the longitudinal distance representation is the recognizable separation of small and large longitudinal dis…
Small behaviour of the chirally-odd parton distribution
R. Kirschner, L. Mankiewicz, A. Schäfer +1
The small behaviour of the structure function is studied within the leading logarithmic approximation of perturbative QCD. There are two contributions relevant at…
Physically Motivated Approximation to a Parton Distribution Function in QCD
L. Mankiewicz, T. Weigl
It has been suggested that parton distributions in coordinate space, so called Ioffe-time distributions, provide a more natural object for non-perturbative methods compared to the…
Dependence of the Bjorken Sum Rule
Lech Mankiewicz, Eckart Stein, Andreas Schäfer
We discuss various estimates of the magnitude of higher-twist corrections to the Bjorken sum rule in polarized deep inelastic scattering.
QCD Sum Rule Calculation of Twist-4 Corrections to Bjorken and Ellis-Jaffe Sum Rules
E. Stein, P. Gornicki, L. Mankiewicz +1
We calculate the twist-4 corrections to the integral of in the framework of QCD sum rules using an interpolating nucleon field which contains explicitly a gluonic degr…
QCD Sum Rule Calculation of Twist-3 Contributions to Polarized Nucleon Structure Functions
E. Stein, P. Gornicki, L. Mankiewicz +2
Using the framework of QCD sum rules we predict the twist-3 contribution to the second moment of the polarized nucleon structure function . As the relevant local operator d…