Samara State University, Samara, Russia XXXIII INTERNATIONAL CONFERENCE ON HIGH ENERGY PHYSICS ICHEP'06 Moscow, 26 July – 2 August 2006 A.F. Krutov Samara State University, Samara, Russia V.E. Troitsky D.V. Skobeltsyn Institutе of Nuclear Physics Moscow State University, Moscow, Russia Relativistic calculation of the neutron charge form factor from the JLab deuteron data

Electromagnetic structure of the nucleons Motivation: Electromagnetic structure of the nucleons , , the momentum transfer. is still known rather poorly. Difficulties: - The lack of a free-neutron target and extraction of the neutron charge form factor from data for composite nuclei Необходимость рел... - Results depend crucially on the model for NN-interaction - Relativistic effects Meson exchange currents - etс.

The present report: The neutron charge form factor is extracted from the experimental data on the deuteron charge form factor obtained through polarization experiment in the JLab.

Modern relativistic calculations of the deuteron structure in the nucleon model are based on the two main classes of approaches: The field-theoretical approaches - Bethe-Salpeter equation - quasipotential approaches Relativistic Hamiltonian dynamics (RHD) - instant form - light-front form - point form Our approach: Instant form of the relativistic Hamiltonian dynamics (RHD) A.F. Krutov, V.E. Troitsky, Phys.Rev.C 65 (2002) 045501 A.F. Krutov, V.E. Troitsky, Phys.Rev.C 68 (2003) 018501 A.F. Krutov, V.E. Troitsky, Theor.Math.Phys. 143 (2005) 704

The main features of our approach: the method of construction of the matrix elements of the electroweak current operator the electroweak current matrix satisfies the relativistic covariance conditions the electromagnetic current satisfies the conservation law The relativistic impulse approximation in our approach: the Lorentz covariance of the currrent is ensured the electromagnetic current consrvation law is ensured

The deuteron charge form factor in our approach in the relativistic impulse approximation:

The charge form factor of the neutron:

Deuteron wave functions in sense of RHD are solution of eigenvalue problem for complete set of commuting operators: Eigenvalue problem for It is Schrödinger equation within a second order on deuteron binding energy: Normalization:

The problem of choosing the model deuteron wave functions Paris potential model Nijmegen I Nijmegen II Nijmegen 93 charge-dependent Bonn model Muzafarov-Troitsky (MT)-wave function from the potentialless approach to the inverse scattering problem

for polarized ed-scattering depends weakly on the nucleon form factors

Relativistic corrections to the

as the test for deuteron wave functions

Function for the elastic ed-scattering

The important features of the MT-wave functions: no form of NN-interaction Hamiltonian is used they are given by dispersion-type integral in terms of experimental phase shifts and mixing parameter the phase shifts at large energy are described by Regge analysis they were obtained from quite general assumptions about analytical properties of quantum amplitudes (Mandelstam representation for the deuteron electrodesintegration amplitude) they have not fitting parameters

The problem of the meson exchange currents (MEC) Siegert theorem [A.J.F.Siegert, Phys.Rev. 52, 787 (1937)] if the electromagnetic current satisfies the consrvation law if the dynamics of the two-particle systems is nonrelativistic (the Schrodinger equation, potential) then the charge density of the exchange current is zero (the contribution of MEC to the charge and quadrupole deuteron form factors is zero)

The experimental values and the result of fitting for the neutron charge form factor

The result of fitting for the neutron charge form factor

The present fitting of the neutron charge form factor will be used in the neutrino scattering experiments in Fermilab [ D.Drakoulakos et al., Proposal to Perform a High-Statistic Neutrino Scattering Experiment Using a Fine-grained Detector in the NuMI Beam, hep-ex/0405002]

Conclusions: the new procedure was suggested for extraction of the neutron charge form factor from charge form factor of deuteron 12 new points for charge neutron form factor were obtained the fitting was performed for 36 values of neutron charge form factor including our points