Total Cross Section Measurements and Velocity Distributions of Hyperthermal Charge Transfer in Xe$^{\mathrm{2+}}+$ N$_{\mathrm{2}}$

Guided-ion beam measurements of the charge exchange (CEX) cross section for Xe$^{\mathrm{2+}}+$ N$_{\mathrm{2}}$ are reported for collision energies ranging from 0.3 to 100 eV in the center-of-mass frame. Measured total XS decrease from 69.5$\pm $0.3 Angstroms$^{\mathrm{2\thinspace }}$(Angs.) at the lowest collision energies to 40 Angs.$^{\mathrm{2}} $at 100 eV. The product N$_{\mathrm{2}}^{\mathrm{+}}$ CEX cross section is similar to the total CEX cross section while those of the dissociative product, N$^{\mathrm{+}}$, are less than 1Angs.$^{\mathrm{2}}$ for collision energies above 9 eV. The product N$_{\mathrm{2}}^{\mathrm{+}}$CEX cross section measured here are much larger than the total optical emission-excitation cross sections for the N$_{\mathrm{2}}^{\mathrm{+}}$ ($A)$ and ($B)$ state products determined previously in the chemiluminescence study of Prince and Chiu suggesting that most of the N$_{\mathrm{2}}^{\mathrm{+}}$ products are in the $X$ state. Time-of-flight (TOF) spectra of both the Xe$^{\mathrm{+}}$ and N$_{\mathrm{2}}^{\mathrm{+}}$ products suggest two different CEX product channels. The first leaves highly-vibrationally excited N$_{\mathrm{2}}^{\mathrm{+}}$ products with forward scattered Xe$^{\mathrm{+}}$ (LAB frame) and releases between 0.35 to 0.6 eV translational energy for collisions below 17.6 eV. The second component decreases with collisional energy and leaves backscattered Xe$^{\mathrm{+}}$ and low-vibrational states of N$_{\mathrm{2}}^{\mathrm{+}}$. At collision energies above 17.6 eV, only charge exchange involving minimal momentum exchange remains in the TOF spectra.