Determination of theQ-value dependence of charged particle emission in the40Ca+40Ca reaction at 10 MeV/nucleon

An iterative method for the determination of the charged particle loss as a function of the reactionQ-value is developped. The analysis is based on experimental data resulting from 400 MeV⁴⁰Ca+⁴⁰Ca collisions.Z distributions are obtained at different calculatedQ-values corrected for evaporation and show rather good agreement — in the strongly damped case — with the ones derived from the OVERLAID ALICE code. Mean numbers of evaporated particles exhibit a linear increase as a function of these correctedQ-values; this corresponds to the evolution from quasi-direct to fully relaxed reactions.     

Algorithms for flows over time with scheduling costs

Mathematical Programming - Flows over time have received substantial attention from both an optimization and (more recently) a game-theoretic perspective. In this model, each arc has an associated...     

Contribution of decay products of transfer reactions to heavy-ion inelastic and transfer spectra

A study of decay product contributions to inclusive ejectile kinetic energy spectra is presented. Analytical formulae for the positions and widths of these contributions are derived from kinematical considerations. A formal integral expression for the double-differential cross section $\text{d}{}^2\text{σ/}\text{d}\text{Ω}\text{d}\text{E}$ is given in the case of one-particle emission from an excited state of the ejectile. The effects of anisotropic angular distributions are studied. The differential cross sections are then computed by a Monte Carlo method and compared to experimental spectra over a large range of measured systems. The transfer-evaporation mechanism is shown to contribute strongly to the background of the spectra but not to be responsible for the narrow structure observed in some reactions.     

Proton-nucleus elastic scattering at 156 MeV

Cross sections for the elastic scattering of 156 MeV protons on eleven targets ranging from ¹²C to ²⁰⁹Bi were measured and an optical model analysis has been performed. The effect of different optical potentials in DWIA inelastic scattering calculations is shown by some examples.     

Transfer and fragmentation reactions of14N at 60 MeV/u

Inclusive energy spectra and cross sections of reaction products close to the¹⁴N projectile (¹¹C,¹²C,¹³C,¹⁵N and¹⁵O) have been measured in the angular rangeθ _L =1.2°–4.2° at an incident energy of 60 MeV/u for five different target nuclei (¹²C,²⁷Al,⁵⁸Ni,⁹⁰Zr and²⁰⁸Pb). Two components are found to be systematically present in the energy spectra of the carbon isotopes, the first similar to that observed at relativistic energies and the second shifted down in energy characteristic for a very dissipative process. The dependence of the differential and integrated cross sections on the target mass indicates that the two-body final channels (¹⁴N,¹³C), (¹⁴N,¹⁵N) and (¹⁴N,¹⁵O) are strongly correlated to the fragmentation channels.     

Search for a Δ++ presence in the 3He nucleus by means of the 3He (p,t) Δ++ reaction

The reaction ³He (p, t) Δ⁺⁺ has been studied to look for evidence of (Δ⁺⁺, 2n) components of the ³He wave function. The experimental conditions, proton energy and triton angles, have been chosen to emphasize such components.     

Measurement of strange-quark contributions to the nucleon's form factors at Q(2) = 0.230 (GeV/c)(2)

We report on a measurement of the parity-violating asymmetry in the scattering of longitudinally polarized electrons on unpolarized protons at a Q2 of 0.230 (GeV/c)(2) and a scattering angle of theta (e) = 30 degrees - 40 degrees. Using a large acceptance fast PbF2 calorimeter with a solid angle of delta omega = 0.62 sr, the A4 experiment is the first parity violation experiment to count individual scattering events. The measured asymmetry is A(phys)=(-5.44+/-0.54(stat)+/-0.26(sys))x10(-6). The standard model expectation assuming no strangeness contributions to the vector form factors is A(0) = (-6.30+/-0.43) x 10(-6). The difference is a direct measurement of the strangeness contribution to the vector form factors of the proton. The extracted value is G(s)(E) + 0.225G(s)(M) = 0.039+/-0.034 or F(s)(1) + 0.130F(s)(2) = 0.032+/-0.028.