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C-. Y. Hu

Publications and source records attributed to C-. Y. Hu.

8 recordsLinked to original sources
arXiv2005

Positron annihilation in $e^+ -$H collision above the Positronium formation threshold

A long-standing problem to account for the electron-positron annihilation in positron Hydrogen scattering above the Positronium formation threshold has been resolved by the use of the three-body Faddeev formalism. The multichannel three-body theory for scattering states in presence of a complex absorbing potential is developed in order to compute the direct $e^+ e^-$ annihilation amplitude, the amplitude of Positronium formation and respective cross sections. A number of $e^+ e^-$ direct annihilation cross sections and Positronium formation cross sections in the energy gap between Ps$(1s)$ and H$(n=2)$ thresholds are reported for both the positron-Hydrogen incoming channel as well as the proton-Positronium incoming channel.

physics.atom-ph↗
arXiv2004

$e^+ + H$ direct annihilation above the positronium formation threshold

A long-standing problem with the solution of the Schrödinger equation has been its inability to account for the electron-positron annihilation in positron hydrogen scattering above the positronium formation threshold. This letter shows that this problem has been resolved by the use of the modified Faddeev equations. A number of $e^- e^+$ annihilation cross sections in the energy gap between $Ps(1s)$ and $H(n=2)$ thresholds are reported for both the positron plus hydrogen incoming channel as well as the proton plus positronium incoming channel. However the indirect annihilation cross sections after formation of the positronium themselves are well known, they will not be included in this report.

physics.atm-clus↗
arXiv2004

Accumulation of three-body resonances above two-body thresholds

We calculate resonances in three-body systems with attractive Coulomb potentials by solving the homogeneous Faddeev-Merkuriev integral equations for complex energies. The equations are solved by using the Coulomb-Sturmian separable expansion approach. This approach provides an exact treatment of the threshold behavior of the three-body Coulombic systems. We considered the negative positronium ion and, besides locating all the previously know $S$-wave resonances, we found a whole bunch of new resonances accumulated just slightly above the two-body thresholds. The way they accumulate indicates that probably there are infinitely many resonances just above the two-body thresholds, and this might be a general property of three-body systems with attractive Coulomb potentials.

physics.atom-ph↗
arXiv2001

Multichannel $e^{\pm}$ scattering on excited Ps states

Scattering and reaction cross sections of $e^{\pm}-Ps$ system are calculated for total angular momentum L=0, 1 and 2 and energies between the Ps(n=2)-Ps(n=3) threshold. We solved a set of Faddeev-Merkuriev and Lippmann-Schwinger integral equations by applying the Coulomb-Sturmian separable expansion technique. We found that the excited positronium states play dominating roles in scattering processes.

physics.atom-ph↗
arXiv2001

Three-potential formalism for the three-body scattering problem with attractive Coulomb interactions

A three-body scattering process in the presence of Coulomb interaction can be decomposed formally into a two-body single channel, a two-body multichannel and a genuine three-body scattering. The corresponding integral equations are coupled Lippmann-Schwinger and Faddeev-Merkuriev integral equations. We solve them by applying the Coulomb-Sturmian separable expansion method. We present elastic scattering and reaction cross sections of the $e^++H$ system both below and above the $H(n=2)$ threshold. We found excellent agreements with previous calculations in most cases.

physics.atom-ph↗