5,021 research outputs found
Precision calculation for nucleon capture by deuteron with Effective Field Theory
We calculate the cross section for radiative capture of neutron by deuteron
using Effective Field Theory(EFT). The calculation includes
N2LO order and we compare our results with available calculated data below
E=0.2 Mev.Comment: 4 pages, 1 eps figures, oral contribution, 19th European Few-Body
Conference (fb19), Groningen, Netherlands, August 23 - August 27, 2004. To be
published in the proceeding
Jet Quenching Parameter with Hyperscaling Violation
In this paper we study the behavior of jet quenching parameter in the
background metric with hyperscaling violation at finite temperature.The
background metric is covariant under a generalized Lifshitz scaling symmetry
with the dynamical exponent z and hyperscaling exponent . We evaluate
the jet quenching parameter for certain range of these parameters consistent
with the Gubser bound conditions in terms of T, z and . We compare our
results with those from conformal case and experimental data. Then we add a
constant electric field to this background and find its effect on the jet
quenching parameter.Comment: 22 pages, 9 figure
Neutron-Deuteron System and Photon Polarization Parameter at Thermal Neutron Energies
Effective Field Theory(EFT) is, the unique, model independent and systematic
low-energy version of QCD for processes involving momenta below the pion mass.
A low-energy photo-nuclear observable in three-body systems, photon
polarization parameter at thermal neutron energies is calculated by using
pionless EFT up to next-to-next to leading order(NLO). In order to make a
comparative study of this model, we compared our results for photon
polarization parameter with the realistic Argonne two-nucleon and
Urbana IX or Tucson-Melbourne three-nucleon interactions. Three-body currents
give small but significant contributions to some of the observables in the
neutron-deuteron radiative capture cross section at thermal neutron energies.
In this formalism the three-nucleon forces are needed up to NLO for cut-off
independent results. Our result converges order by order in low energy
expansion and also cut-off independent at this order.Comment: 10 pages, 3 figures, 2 table
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