Zobrazeno 1 - 10
of 240
pro vyhledávání: '"Gribakin, G F"'
An implementation of the Hartree-Fock (HF) method capable of robust convergence for well-behaved arbitrary central potentials is presented. The Hartree-Fock equations are converted to a generalized eigenvalue problem by employing a B-spline basis in
Externí odkaz:
http://arxiv.org/abs/2108.05850
The effect of confinement on the self-annihilation rate of positronium is studied in three levels of approximation. Artificial restriction of the electron-positron separation leads to an increase in the annihilation rate over its vacuum value; this i
Externí odkaz:
http://arxiv.org/abs/2108.01966
Publikováno v:
Phys. Rev. A 107, 042802 (2023)
The many-body-theory approach to positronium-atom interactions developed in [Phys. Rev. Lett. \textbf{120}, 183402 (2018)] is applied to the sequence of noble-gas atoms He-Xe. The Dyson equation is solved separately for an electron and positron movin
Externí odkaz:
http://arxiv.org/abs/2105.06749
Publikováno v:
Phys. Rev. A 104, 012813 (2021)
Measured and calculated positron binding energies are presented for a range of hydrocarbons with up to six carbon atoms (viz., methane, acetylene, ethylene, ethane, propane, butane, and hexane) and their chlorinated counterparts. Both experiment and
Externí odkaz:
http://arxiv.org/abs/2104.05338
Autor:
Swann, A. R., Gribakin, G. F.
Publikováno v:
J. Chem. Phys. 153, 184311 (2020)
The model-potential approach previously developed by the authors to study positron interactions with molecules is used to calculate the positron binding energy for $n$-alkanes (C$_n$H$_{2n+2}$) and the corresponding cycloalkanes (C$_n$H$_{2n}$). For
Externí odkaz:
http://arxiv.org/abs/2009.00998
Autor:
Swann, A. R., Gribakin, G. F.
Publikováno v:
Phys. Rev. A 101, 022702 (2020)
A model-potential method is employed to calculate binding, elastic scattering, and annihilation of positrons for a number of atoms and small nonpolar molecules, namely, Be, Mg, He, Ar, H$_2$, N$_2$, Cl$_2$, and CH$_4$. The model potential contains on
Externí odkaz:
http://arxiv.org/abs/1912.03051
Autor:
Swann, A. R., Gribakin, G. F.
Publikováno v:
Phys. Rev. Lett. 123, 113402 (2019)
A model-potential approach has been developed to study positron interactions with molecules. Binding energies and annihilation rates are calculated for positron bound states with a range of alkane molecules, including rings and isomers. The calculate
Externí odkaz:
http://arxiv.org/abs/1904.12491
Autor:
Swann, A. R., Gribakin, G. F.
Publikováno v:
J. Chem. Phys. 149, 224305 (2018)
A model-potential approach to calculating positron-molecule binding energies and annihilation rates is developed. Unlike existing ab initio calculations, which have mostly been applied to strongly polar molecules, the present methodology can be appli
Externí odkaz:
http://arxiv.org/abs/1809.03250
Autor:
Law, S. M. K., Gribakin, G. F.
We investigate orbital alignment dynamics within the valence shell of atoms in coherently excited $j=3/2,1/2$ fine-structure manifolds generated by short-pulse photodetachment of F$^-$, Cl$^-$ and Br$^-$ anions. Using Keldysh-type theory, we calculat
Externí odkaz:
http://arxiv.org/abs/1808.05512
Autor:
Swann, A. R., Gribakin, G. F.
Publikováno v:
Phys. Rev. A 97, 012706 (2018)
Positronium (Ps) scattering by noble-gas atoms (He, Ne, Ar, Kr, and Xe) is studied in the frozen-target approximation and with inclusion of the van der Waals interaction. Single-particle electron and positron states in the field of the target atom ar
Externí odkaz:
http://arxiv.org/abs/1712.05127