Quadrupole association and dissociation of hydrogen in the early Universe

Abstract

Radiative association and photodissociation rates are calculated for quadrupole transitions of H2. A complete set of bound and unbound states are included in a self-consistent master equation to obtain steady-state concentrations for a dilute system of hydrogen atoms and molecules. Phenomenological rate constants computed from the steady-state concentrations satisfy detailed balance for any combination of matter and radiation temperature. Simple formulas are derived for expressing the steady-state distributions in terms of equilibrium distributions. The rate constant for radiative association is found to be generally small for all temperature combinations. The photodissociation rate constant for quadrupole transitions is found to dominate the rate constants for other H2 photodestruction mechanisms for radiation temperatures less than or equal to 3000 K. Implications for the formation and destruction of H2 in the early universe are discussed.

References in corpus (4)

• The critical radiation intensity for direct collapse black hole formation: dependence on the radiation spectral shape
• Vibrational level population of H${}_2$ and H${}_2^{+}$ in the early Universe
• Role of the H${}_2^{+}$ channel in the primordial star formation under strong radiation field and the critical intensity for the supermassive star formation
• Formation of silicon monoxide by radiative association: the impact of resonances

Cited by in corpus (3)

• Precision measurement of quasi-bound resonances in H${}_2$ and the H + H scattering length
• Shape resonances in H${}_2$ as photolysis reaction intermediates
• The quasi bound spectrum of H2