Energy-dependent relative charge transfer cross sections of Cs+ + Rb(5s, 5p)

Magneto optical trap recoil ion momentum spectroscopy is used to measure energy-dependent charge exchange cross sections in the Cs+ + Rb(5s, 5p) system over a range of projectile energies from 3.2 to 6.4 keV. The measurements are kinematically complete and yield cross sections that are differential in collision energy, scattering angle, and initial and final states

Ultrafast dynamics of correlation bands following XUV molecular photoionization

Interstellar matter and star formatio

Multi electron capture processes in slow collisions between X

Electron capture processes in collision between slow X7+ (X = N, O and Ne) ions and C60 fullerene have been investigated using coincident measurements of the number n of ejected electrons, the mass and charge of the multicharged C60r+ recoil ions and their fragments Cmi+ and the final charge state of the outgoing projectiles X(q-s)+ ($1 \leqslant s \leqslant q-1$). The collision velocity is about 0.4 a.u. The partial cross-sections σrs , corresponding to r electrons transferred to the projectile with only s electrons stabilized, have been measured. Cross-sections for collisions “inside” and those “outside” the C60 cage have been separated by analyzing the kinetic energy of the outgoing projectile. The mean final charge state for frontal collisions has been measured to 3.1, 2.6 and 2.5 for N7+, O7+ and Ne7+ respectively. These results show the importance of the core effect on the stabilisation processes of captured electrons

MOTRIMS as a generalized probe of AMO processes

Magneto-optical trap recoil ion momentum spectroscopy (MOTRIMS) is one of the newest offshoots of the generalized TRIMS approach to ion–atom collisions. By using lasers instead of the more usual supersonic expansion to cool the target, MOTRIMS has demonstrated two distinct advantages over conventional TRIMS. The first is better resolution, now limited by detectors instead of target temperature. The second is its suitability for use in the study of laser-excited targets. In this presentation we will present a third advantage: The use of MOTRIMS as a general-purpose probe of AMO processes in cold atomic clouds of atoms and molecules. Specifically, the projectile ion beam can be used as a probe of processes as diverse as target dressing by femtosecond optical pulses, photo-association (laser-assisted cold collisions) photo-ionization, and electromagnetically-induced transparency. We will present data for the processes we have investigated, and speculations on what we expect to see for the processes we plan to investigate in the future

Branching ratios of successive emission (up to three) of C

Highly charged C60 molecules are produced in collisions between neutral C60 and multiply charged ions within a large range of temperatures. Successive emission of one, two or three light monocharged fragments referred as one-, two- and three-step processes have been observed. The experimental mass branching ratios for the emission of one C$_{2n}^{+}$ fragment from C$_{60}^{6+}$, C$_{60}^{5+}$ and C$_{60}^{4+}$ ions are compared with the theoretical values using a statistical model. From hotter C$_{60}^{6+}$ ions, branching ratios for three-step processes have been measured and the data are in good agreement with an estimation using the branching ratios in one-step process

Ejection of a doubly charged light fragment in asymmetric fission of multiply charged fullerenes

In \chem{Ar^{8+}}-\chem{C_{60}} collisions, quintuply charged fullerene \chem{{C_{60}}^{5+}} is produced via multiple electron capture by slow highly charged ions from neutral fullerenes. Quasi-symmetric charge division (3, 2) is observed in asymmetric mass division fission processes, i.e. \chem{{C_{60}}^{5+}\rightarrow} \chem{C} ${_{60-m}}^{3+} +$ \chem{C} ${_m}^{++}$ ($m\ll60$). In such fission channels, the charge density of the doubly charged light fragment is much higher than that of the triply charged heavy one. The measured population distribution as a function of the mass of the doubly charged fragment m is interpreted tentatively by fission barrier analyses

Fragmentation of doubly charged HDO, H2O, and D2O molecules induced by proton and monocharged fluorine beam impact at 3 keV

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