Related papers: o-Positronium scattering off H and He
We describe a new method to treat low-energy scattering problems in few-nucleon systems, and we apply it to the five-body case of neutron-alpha scattering. The method allows precise calculations of low-lying resonances and their widths. We…
European perspectives are discussed on fixed-target electron or positron scattering experiments using polarized and unpolarized beams and targets in various combinations. The goal envisioned is a deep and complete understanding of the…
An improved model of the multiple Dirac eikonal scattering of proton on nucleons of the target nucleus is considered. In this model, the amplitudes of elastic $p-A$ scattering are found on the basis of the Watson series of multiple…
A method to treat a N-component percolation model as effective one component model is presented by introducing a scaled control variable $p_{+}$. In Monte Carlo simulations on $16^{3}$, $32^{3}$, $64^{3}$ and $128^{3}$ simple cubic lattices…
We consider elastic reflection and transmission of electrons by a disordered system characterized by a $2N\!\times\!2N$ scattering matrix $S$. Expressing $S$ in terms of the $N$ radial parameters and of the four $N\!\times\!N$ unitary…
Direct sampling of multi-dimensional systems with quantum Monte Carlo methods allows exact account of many-body effects or particle correlations. The most straightforward approach to solve the Schr\"odinger equation, Diffusion Monte Carlo,…
We describe a Monte Carlo procedure which allows sampling of the disjoint configuration spaces associated with crystalline and fluid phases, within a single simulation. The method utilises biased sampling techniques to enhance the…
An accurate method to compute the annihilation rate in positronic systems by means of quantum Monte Carlo simulations is tested and compared with previously proposed methods using simple model systems. This method can be applied within all…
The differential cross sections for low-energy muonic hydrogen atom scattering in solid molecular H$_2$, D$_2$ and T$_2$ targets under low pressure have been calculated for various temperatures. The polycrystalline fcc and hcp structure of…
The elastic scattering cross sections for a slow electron by C2 and H2 molecules have been calculated within the framework of the non-overlapping atomic potential model. For the amplitudes of the multiple electron scattering by a target the…
The study of polarized radiation transfer in the highly-magnetized surface locales of neutron stars is of great interest to the understanding of accreting X-ray pulsars, rotation-powered pulsars and magnetars. This paper explores scattering…
Hyperfine splitting of positronium is an important parameter for particle physics. This paper gives experimental techniques and results of R&D studies of our experiment to observe direct hyperfine transition of ortho-positronium to…
The J-matrix method of scattering is used to obtain analytic expressions for the phase shift of two classes of relativistic exponential-type separable potentials whose radial component is either of the general form r^(n-1)exp(-r) or…
A review of measurements of the total cross section in ppbar collisions at the TEVATRON and an outlook on the expected performance for similar determinations at the LHC is given. The experimental method is based on the optical theorem to…
Differential cross sections are computed for the title polar molecule using static interaction, exchange forces and correlation-polarisation effects as described in detail in the main text. The dipole effect is also reported via the dipole…
We present an experimental study on the rotational inelastic scattering of OH ($X^2\Pi_{3/2}, J=3/2, f$) radicals with He and D$_2$ at collision energies between 100 and 500 cm$^{-1}$ in a crossed beam experiment. The OH radicals are state…
The optical theorem allowing the determination of the total cross section for a hadron-hadron scattering from the imaginary part of the forward elastic scattering amplitude is believed to be an unavoidable consequence of the conservation of…
We apply the Linked Dipole Chain model to hadronic collisions using a modified version of the LDCMC Monte Carlo program. In particular we investigate the effects of multiple scatterings, which in this framework are reformulated in terms of…
We report on the first quantum Monte Carlo calculations of helium isotopes with fully propagated theoretical uncertainties from the interaction to the many-body observables. To achieve this, we build emulators for solutions to the Faddeev…
We calculate the $T$-matrices of elastic pion-nucleon ($\pi N$) scattering up to fourth order in SU(3) heavy baryon chiral perturbation theory. The pertinent low-energy constants are determined by fitting to $\pi N$ phase shifts below 200…