Radiation Fields

Radiation fields.
Inset figure solid line: The ISRF (Draine 1978 and extension) radiation field.
Inset figure dashed line: The Mathis 1983 (DG = 10 kpc) radiation field.
Inset figure dotted line: The Habing 1968 radiation field.
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Details of the radiation fields used in the calculation of rates in this website are given in the overview papers. The figure above shows the photon intensity assuming different interstellar radiation fields. The "standard ISRF" adopted in this website is taken from Draine 1978 between 91.2 and 200 nm, and with the extension of van Dishoeck & Black 1982 at longer wavelengths.

The wavelength dependence of the Solar ultraviolet flux was compiled from the quiet-Sun measurements of Curdt et al. 2001 and Woods et al. 1996.

The TW-Hydra radiation field simulates the wavelength dependence of UV emission from this classical T-Tauri star and based on the work of France et al. 2014 and Nomura & Milar 2005.

The various blackbody-emission radiation fields are defined by a single temperature, and we have chosen to suppress all flux at wavelengths shorter than 91.2 nm to account for interstellar extinction by atomic hydrogen.

All radiation fields have been scaled to agree with the integrated energy-intensity of the Draine 1978 radiation field between 91.2 and 200 nm, apart from the Mathis 1983 and Habing 1968 radiation fields which are used with their original overall scaling.

For a description of cosmic-ray generated flux please consult Heays et al. 2017, and Gredel et al. 1987 and 1989.

Download radiation fields in numerical format