Clara Illescas

Classical calculation of ionization and electron-capture total cross sections in H{sup +}+H{sub 2}O collisions

We report total cross sections for single ionization and electron capture in H{sup +} collisions with water molecules at impact energies 25 keV<E<5 MeV. Calculations have been carried out by applying the independent-particle model and the eikonal-classical trajectory Monte Carlo (CTMC) method. We have also estimated fragmentation cross sections by multiplying the partial cross sections by the branching ratios measured in the photoionization experiments of Tan et al. [Chem. Phys. Lett. 29, 299 (1978)].

Classical treatment of collisions

Using a classical treatment in the frame of an independent particle model with an effective Hamiltonian, we calculate capture and ionization cross sections for collisions in the impact energy range , and compare our data with those of three sets of experiments and with those for collisions.

Classical and semi-classical treatments of Li3+, Ne10++H(1s) collisions

We perform molecular close-coupling and impact-parameter classical trajectory Monte Carlo calculations of total and partial cross sections for capture and ionization in collisions of highly charged ions on H(1s). We first consider Li3++H(1s) as a benchmark to ascertain the complementarity of the methods, and then Ne10++H(1s), which has been scarcely studied up to now, and has recently become of interest for fusion plasma research.

Ionization dynamics in interactions of atoms with ultra-short and intense laser pulses

Atom ionization by intense laser pulses, whose electric field performs less than two oscillations during the pulse, is investigated theoretically using both quantum and classical approaches. We show that, under these conditions, the ionization process exhibits a classical aspect. Further, up to laser field amplitudes comparable to the Coulomb field of the nucleus, which is experienced by the active electron on its initial target orbital, the nuclear field is shown to play a significant role in the dynamics of ionization. For higher laser fields, a simple approach based on Coulomb-Volkov states appears much more convenient than full numerical treatments.

Calculation of total cross sections and effective emission coefficients for B5 + collisions with ground-state and excited hydrogen

Classical and semiclassical calculations of nl-resolved charge exchange cross sections in B5 + collisions with H(ni) are performed to compute effective emission coefficients for the n = 7 → n = 6 transition in B4 + for plasma conditions typical of the ASDEX-U tokamak. For ni = 1, the value of the emission coefficient is larger than that obtained from ADAS database by a factor of 2 at energies of 10 , but no differences are found at energies above 50 . For ni = 2, our calculation yields emission coefficients close to those derived from ADAS data from low to high impact energies. The emission coefficients corresponding to B5 + + H(ni = 3) collisions are of the same order of magnitude as those for ni = 2.

Ionization and electron capture in ion-molecule collisions: classical (CTMC) and semiclassical calculations.

Total cross-sections for electron capture and electron production in proton collisions with N2, CO and H2O, are evaluated using a classical trajectory Monte Carlo treatment for collision energies between 30 and 3000 keV. A semiclassical close-coupling treatment has been also employed for proton collisions with H2O, to discuss the accuracy of the CTMC treatment. Singly differential cross-sections for electron production have been also evaluated. Total and differential cross are compared with experimental data.

Collisions of highly charged ions with hydrogen relevant to plasma diagnostics

We present total cross sections for ionization, and total and nl-partial cross sections for electron capture in collisions of Kr36+ and W60+ with H(1s). Calculations have been carried out using the classical trajectory Monte Carlo method. We have found that scaling laws as functions of the ion charge are valid for total electron capture cross sections, but they are less accurate for n-partial cross sections. The nl-partial cross sections show l distributions similar to those found for collisions with Ar18+ by Errea et al (2006 J. Phys. B: At. Mol. Opt. Phys. 39 L91).

Electron capture and nuclear exchange in H+ + H2 collisions at low impact energies

Electron capture, vibrational excitation, dissociation and nuclear exchange in collisions of H+ with H2 are studied at impact energies between 5 eV and 1 keV. Calculations are performed by employing classical trajectories for the nuclear evolution and a three-state expansion of the electronic wavefunction that uses the diatomics in molecules approach. Our results confirm previous vibronic results and show a striking discrepancy in single capture cross sections with experimental data for energies E≤ 200 eV.

Charge transfer and ionization involving Argon ions and neutral Hydrogen

A device is disclosed for reconstitution and delivery of an injectable pharmaceutical. A pharmaceutical composition such as a lyophilized drug is provided in a pressurizable fluid reservoir with a pierceable seal. A diluent may be separately provided in a syringe with a needle. When the needle is driven through the seal and the plunger is actuated, fluid from the barrel of the syringe flows into the pressurizable fluid reservoir to simultaneously pressurize the reservoir and mix the diluent with the drug. Pressurized in this manner, the reservoir can then automatically and without further user intervention push the mixture back through the needle and into the barrel of the syringe, further mixing the composition and displacing the plunger to fill the barrel with the reconstituted drug. The needle and syringe can then be detached from the reservoir with the reconstituted drug contained in the barrel and ready for injection.

Calculation of total cross sections for electron capture in collisions of Carbon ions with H(D,T)(1s)

The calculations of total cross sections of electron capture in collisions of Cq+ with H(1s) are reviewed. At low collision energies, new calculations have been performed, using molecular expansions, to analyze isotope effects. The Classical Trajectory Monte Carlo method have been also applied to discuss the accuracy of previous calculations and to extend the energy range of the available cross sections.