Ionization study of cyanopolyynes HCnN (n = 1-17) by electron and positron impact

Abstract In this work, we investigate how electrons and positrons interact with
 important space molecules, specifically cyanopolyynes HCnN(n= 1-17). These are
 linear molecules detected in the interstellar medium (ISM) and observed in regions
 like Sgr B2, Taurus Molecular Cloud-1 (TMC-1), the circumstellar envelope of the
 carbon star IRC +10216, and cold molecular clouds. We apply the binary-encounter
 Bethe (BEB) model to determine the ionization cross sections for both electron
 and positron impacts on these molecules, covering an energy range from ionization
 threshold to 5 keV. These molecules play a crucial role in astrophysics, astrochemistry,
 and atmospheric studies. However, their data are limited, particularly concerning
 positron impact ionization, which is being calculated for the first time in this study.
 Due to the complexity of these molecules, experimental data are lacking and only
 a small amount of theoretical information is currently available. Additionally, we
 have calculated properties like polarizability, dipole moment and highest occupied
 molecular orbital (HOMO) energy for these molecules using the Hartree-Fock (HF)
 approximation. We have also studied the correlation of the maximum ionization cross
 section with the polarizability and ionization energy of the targets. These data are
 important for understanding cyanopolyynes and will help scientists model chemical
 processes in space.