arXiv subjects

S. Elhandi

Publications and source records attributed to S. Elhandi.

3 recordsLinked to original sources

arXiv2010

Electron's anomalous magnetic moment effects on electron-hydrogen elastic collisions in the presence of a circularly polarized laser field

The effect of the electron's anomalous magnetic moment on the relativistic electronic dressing for the process of electron-hydrogen atom elastic collisions is investigated. We consider a laser field with circular polarization and various electric field strengths. The Dirac-Volkov states taking into account this anomaly are used to describe the process in the first order of perturbation theory. The correlation between the terms coming from this anomaly and the electric field strength gives rise to new results, namely the strong dependence of the spinor part of the differential cross section (DCS) with respect to these terms. A detailed study has been devoted to the non relativistic regime as well as the moderate relativistic regime. Some aspects of this dependence as well as the dynamical behavior of the DCS in the relativistic regime have been addressed.

physics.atom-ph↗

arXiv2009

Mott scattering in strong laser field revisited

In this work, we review and correct the first Born differential cross section for the process of Mott scattering of a Dirac-Volkov electron, namely, the expression (26) derived by Szymanowski et al [Physical Review A {\bf 56}, 3846 (1997)]. In particular, we disagree with the expression of $(\frac{dσ}{dΩ})$ they obtained and we give the exact coefficients multiplying the various Bessel functions appearing in the scattering differential cross section. Comparison of our numerical calculations with those of Szymanowski et al. shows qualitative and quantitative differences when the incoming total electron energy and the electric field strength are increased particularly in the direction of the laser propagation. Such corrections are very important since the relativistic electronic dressing of any Dirac-Volkov charged particle gives rise to these coefficients that multiply the various Bessel functions and the relativistic study of other processes (such as excitation, ionisation, etc....) depends strongly of the correctness and reliability of the calculations for this process of Mott Scattering in presence of a laser field. Our work has been accepted [Y. Attaourti, B. Manaut, Physical Review A {\bf 68}, 067401 (2003)] but only as a comment. In this paper, we give the full details of the calculations as well as the clear explanation of the large discrepancies that their results could cause when working in the ultra relativistic regime and using a very strong laser field corresponding to an electric field $\varepsilon=5.89$ in atomic units.

physics.atom-ph↗

arXiv2008

Mott Scattering of polarized electrons in a circularly polarized laser field

We present a study of Mott scattering of polarized electrons in the presence of a laser field with circular polarization using the helicity formalism and the introduction of the well known concept of non flip differential cross section as well as that of flip differential cross section. The results we have obtained in the presence of a laser field are coherent with those obtained in the absence of a laser field. We have studied the relativistic regime as well as the non relativistic regime that are precisely defined in the text. Two important consistency checks have been carried out successfully. The first one is that the sum of both differential cross sections (one with spin up, the other with spin down) always gives the unpolarized differential cross section. The second one is that the relativistic unpolarized differential cross section converges to the non relativistic differential cross section in the limit of small velocities. Moreover, the results obtained using the sofware Reduce \cite{8} gave rise to non contracted coefficients that have been dealt with using the geometry chosen.

physics.atom-ph↗