Esam Ali

Electron Impact Ionization Dynamics of para -benzoquinone

Triple differential cross sections (TDCSs) for the electron impact ionization of the unresolved combination of the 4 highest occupied molecular orbitals (4b3g, 5b2u, 1b1g, and 2b3u) of para-benzoquinone are reported. These were obtained in an asymmetric coplanar geometry with the scattered electron being observed at the angles -7.5°, -10.0°, -12.5° and -15.0°. The experimental cross sections are compared to theoretical calculations performed at the molecular 3-body distorted wave level, with a marginal level of agreement between them being found. The character of the ionized orbitals, through calculated momentum profiles, provides some qualitative interpretation for the measured angular distributions of the TDCS.

Experimental and theoretical study of electron-impact ionization plus excitation of aligned H2

We report quadruple differential cross sections for electron-impact ionization of with simultaneous excitation of the ion which will immediately dissociate. The alignment of the molecule is determined by detecting the emitted proton. The first measurements of this type were recently reported (2013 Phys. Rev. A 88 062705). Here we report measurements with much better angular resolution using the COLTRIMS method. Experimental results are compared with molecular 4-body distorted wave calculations and reasonably good agreement between experiment and theory is found.

Theoretical and experimental study of (e,2e) ionization of the CO2 (1πg) molecule at 250 eV

Triple differential cross sections (TDCSs) of the electron-impact ionization of carbon dioxide are measured in the coplanar asymmetric geometry, with incident electron energy value of 250eV, and ejected electron of 37eV. We will report the experimental results in comparison with the theoretical calculations of the M3DW and TCC (type 5) calculations.