ECAMP 15

Collisions between charged and neutral particles play a central role in atomic and molecular physics. A significant area of investigation lies in the study of electron and positron impact single ionization of atomic and molecular targets, known as (e,2e) processes, which shed light on the behavior of electrons and positrons during their interaction with the target in the entry channel, as well as their interactions with all resulting particles in the exit channel. This phenomenon provides valuable insights into fundamental atomic and molecular processes. The ionization of the nitrogen molecule (N₂) is particularly important to study, as nitrogen is a key component of biological materials, including proteins and DNA. Understanding its ionization process offers critical insights into both fundamental physics and its applications in biological and medical research.
In this study, we present theoretical triple differential cross sections (TDCS) for the ionization of nitrogen molecule (N2) induced by both electron and positron impact, in the intermediate energy regime. Calculations are performed using three coulomb waves with variable charge model which was successfully applied for atoms [1] and H2O molecule [2] and extended here for N2 molecule. The model, called M3CWZ, also incorporates the post-collisional interaction (PCI). The TDCS results are obtained in asymmetric coplanar geometry for the outermost molecular orbital 3σg and compared with the previous theoretical result of DWBA model [3] as well as the experimental data taken from [4] De Lucio et al 2016 Physical Review. A. The comparison indicates an overall good agreement between our results and the experimental observations.

References:
[1] Bechane K., Houamer S., Khatir T., Tamin A., & Cappello, C. D. (2024). Electron-impact ionization of argon 3p in asymmetric kinematics. Physical Review. A/Physical Review, A, 109(1).
[2] Tamin, A., Houamer, S., Khatir, T., Ancarani, L. U., & Dal Cappello, C. (2024). Electron-impact ionization of water molecules at low impact energies. The Journal of Chemical Physics, 161(16), 164305.
[3] Purohit, G., & Kato, D. (2018). Projectile charge effects on the differential cross sections for the ionization of molecular nitrogen by positrons and electrons. Journal of Physics B: Atomic, Molecular and Optical Physics, 51(13), 135202.
[4] De Lucio, O. G., & DuBois, R. D. (2016). Differential studies and projectile charge effects in ionization of molecular nitrogen by positron and electron impact. Physical Review. A/Physical Review, A, 93(3).