Role of the $\mathrm{H}_2^+$ channel in the primordial star formation under strong radiation field and the critical intensity for the supermassive star formation

摘要: We investigate the role of H_2^+ channel on H_2 molecule formation during collapse primordial gas clouds immersed in strong radiation fields which are assumed to have shape a diluted black-body spectra with temperature T_rad. Since photodissociation rate depends its level population, we take full account vibrationally-resolved kinetics. find that under soft but intense spectral T_rad 7000 K, H^- takes over production molecular hydrogen. calculate critical intensity needed for supermassive star by direct and examine dependence population. Under assumption local thermodynamic equilibrium (LTE) is underestimated factor few < K. For harder spectra, value not affected population H_2^+. This result justifies previous estimates assuming LTE populations since sources like young and/or metal-poor galaxies predicted rather hard spectra.