The Embattled General: Sir Richard Turner and the First World War (Book Review) by William F. Stewart

Review of The Embattled General: Sir Richard Turner and the First World War by William F. Stewar

Continuum states of CO+

Continuum states of the CO+ cation are studied as a function of internuclear distances in the range 1.7-3.0 a(0). R-matrix wavefunctions are constructed for 1Sigma(+), (2)Pi, (2)Delta and 4Pi total symmetries by study of collisions of electrons with a CO2+ target. Complex quantum defects are obtained from above threshold energy scattering calculations, yielding resonance energy curves and corresponding electronic couplings to the CO+ continuum. Results are presented and discussed for the high-n Feshbach resonances of the CO+ spectrum converging to excited states of CO2+. These curves are responsible for the recently observed dissociative recombination of Co2+

Resonances in electron-impact electron detachment of C-2(-)

Molecular R-matrix with pseudostate calculations are reported for the electron-impact ionization cross section of the carbon dimer anion. A (1)Sigma(+)(g) g resonance is found near the detachment threshold and two further resonances, of (3)Pi(g) and (1)Pi(g) symmetry, are found near 10 eV close to the structures observed experimentally. These unusual shape resonances are a result of the competition between the repulsive Coulomb interaction and the large, attractive polarizability of C-2(-). Use of the Born approximation to allow for higher partial waves gives a total cross section close to that observed experimentally

Electron-impact rotational excitation of symetric-top molecular ions

We present electron-impact rotational excitation calculations for polyatomic molecular ions. The theory developed in this paper is an extension of the work of Rabadán et al (Rabadán I, Sarpal B K and Tennyson J 1998 J. Phys. B: At. Mol. Opt. Phys. 31 2077) on linear molecular ions to the case of symmetric-top species. The H3+ and H3O+ ions, as well as their deuterated forms D3+ and D3O+, are used as test cases and cross sections are obtained at various levels of approximation for impact energies up to 5 eV. As in the linear case, the widely used Coulomb–Born (CB) approximation is found to be unreliable in two major aspects: transitions with ΔJ > 1 are entirely dominated by short-range interactions and threshold effects are important at very low energies. Electron collisional selection rules are found to be consistent with the CB theory. In particular, dominant transitions are those for which ΔJ ≤ 2 and ΔK = 0

The Status of Spectroscopic Data for the Exoplanet Characterisation Missions

The status of laboratory spectroscopic data for exoplanet characterisation missions such as EChO is reviewed. For many molecules (eg H2O, CO, CO2, H3+, O2, O3) the data are already available. For the other species work is actively in progress constructing this data. Much of the is work is being undertaken by ExoMol project (www.exomol.com). This information will be used to construct and EChO-specific spectroscopic database.Comment: Experimental Astronomy, accepte