Quasi-free limit in the deuteron-deuteron three-body break-up process

Detailed measurements of vector and tensor analyzing powers of the ^{2}{\rm H}(\vec d,dp){n} break-up process are presented. The data were obtained using a polarized deuteron-beam with an energy of 65 MeV/nucleon impinging on a liquid-deuterium target. The experiment was conducted at the AGOR facility at KVI using the BINA 4\piπ-detection system. The focus of this contribution is to analyze data of the dddd scattering process in the regime at which the neutron acts as a spectator, which we refer to as the quasi-free (QF) limit. To achieve this, events for which the final-state deuteron and proton are coplanar have been analyzed and the data have been sorted for various reconstructed momenta of the missing neutron. In the limit of vanishing neutron momentum and at small deuteron-proton momentum transfer, the data match very well with measured and predicted spin observables of the elastic deuteron-proton scattering process. The agreement deteriorates rapidly with increasing neutron momentum and deuteron-proton momentum transfer. The results of coplanar configurations in four-body phase space are compared with the results of recent available theoretical calculations based on the Single-Scattering Approximation.

NUCLEAR MOMENTUM DISTRIBUTION WITH FRACTIONAL OCCUPATION PROBABILITIES OF THE SURFACE ORBITS

Simplified expressions for calculating nucléon momentum distributions are derived in the context of the harmonic oscillator shell model and in its modification in which fractional occupation probabilities of the surface orbits are used. The method is applied to study the proton momentum distribution of the spherical nucleus 40Ca. The values of the partial occupation probabilities used had been previously determined by fitting to the experimental elastic form factor data.

An analytical formula for proton momentum distribution in nuclei with A>4

A successful analytical formula for the proton momentum distribution in all nuclei with A>4 accounting for nucleon-nucleon correlation effects, is presented. In this formula the Isomorphic Shell Model wave functions are employed, which are readily available for all nuclei all the way up to 2 0 8Pb. However, other wave functions (e.g., shell model or Hartree-Fock) could be used with almost equivalent results. Available experimental data for 4He, 1 2C and 5 6Fe and predictions of other theories, e.g., for 4 0Ca, are used for comparison of the predictions of the present formula. A reservation is kept concerning the validity of this formula for the momentum distribution of exotic nuclei.

Proton Momentum Distributions in Strong Hydrogen Bonds in the Solid State

Neutron Compton scattering (NCS) is a unique experimental technique made possible by the [...]

Proton momentum distributions and elastic electron scattering form factors for some Ge isotopes

The proton momentum distributions (PMD) and the elasticelectron scattering form factors F(q) of the ground state for someeven mass nuclei in the 2p-1f shell for 70Ge, 72Ge, 74Ge and 76Ge arecalculated by using the Coherent Density Fluctuation Model (CDFM)and expressed in terms of the fluctuation function (weight function)|F(x)|2. The fluctuation function has been related to the chargedensity distribution (CDD) of the nuclei and determined from thetheory and experiment. The property of the long-tail behavior at highmomentum region of the proton momentum distribution has beenobtained by both the theoretical and experimental fluctuationfunctions. The calculated form factors F (q) of all nuclei under studyare in good agreement with those of experimental data throughout allvalues of momentum transfer q.

Collimated proton beams from magnetized near-critical plasmas

Generation of collimated proton beams by linearly and circularly polarized (CP) lasers from magnetized near-critical plasmas has been investigated with the help of three-dimensional (3D) particle-in-cell (PIC) simulations. Due to cyclotron effects, the transverse proton momentum gets significantly reduced in the presence of an axial magnetic field which leads to an enhancement in collimation. Collimation is observed to be highest in case of a linearly polarized (LP) laser in the presence of magnetic field. However, protons accelerated by a right CP laser in the presence of magnetic field are not only highly collimated but are also more energetic than those accelerated by the LP laser. Although, the presence of an axial magnetic field enhances the collimation by reducing the transverse proton momentum, the maximum proton energy gets reduced since the transverse proton momentum has a significant contribution towards proton energy.