All Tables

Table 1: Statistical properties of the ortho and para forms of D₂ (Herzberg 1950). The ortho nuclear spin states are associated with even values of the rotational quantum number, J, and the para states with odd J. Only the lowest rotational level of each modification was included in the model. For D₂⁺ and D₂H⁺, the statistical properties of the lowest ortho and para levels are the same as in the case of D₂; but the lowest para level lies 42.0 K and 50.2 K, respectively, above the lowest ortho level, which is the ground level (Polyansky & Tennyson 1999; Ramanlal & Tennyson 2004).
Table 2: Statistical properties of the energy levels of D₃⁺ with J = 0 and J = 1. J is the rotational quantum number and K its projection on the molecular symmetry axis; g_I is the nuclear spin statistical weight. Only the two lowest energy levels, of A1 and E symmetry, were included in the model. The energies were computed by Polyansky & Tennyson (1999). Note that 1 cm $^{-1} \equiv 1.4388$ K.
Table 3: Requisite column densities for unit optical depth in the absorption line centre for the deuterated forms of H₃⁺. Spectroscopic data from Ramanlal & Tennyson (2004).
Table A.1: Rate coefficients adopted in our chemical model for the reactions relating to the meta, ortho and para forms of multiply-deuterated species. The parameters $\alpha$ , $\beta$ , and $\gamma$ define the rate coefficients k (cm³ s^-1) at temperature T through the relation k = J $(a_{\rm g}, T)\gamma (T/300)^{\alpha } {\rm exp}(-\beta /T)$ ; J allows for Coulomb focusing in reactions of positive ions and negatively charged grains (Draine & Sutin 1987, Eq. (3.4)); $a_{\rm g}$ = 0.1 $\mu$ m is adopted in the table. The rates (s^-1) of reactions induced directly by cosmic rays (crp) are given by $\gamma \zeta$ , where $\zeta$ is the rate of cosmic ray ionization of H₂. "g'' denotes "grain'', "m'', "o'' and "p'' denote "meta'', "ortho'' and "para'', respectively. Key reactions are in bold face. Numbers in parentheses are powers of 10. (The present table is complementary to that in Appendix A of Walmsley et al. 2004.)