Absorption and photoionization cross sections of CO₂, CO, Ar, and He at intense solar emission lines

Abstract

Photoionization and total absorption cross sections have been measured for CO2, CO, Ar, and He at the wavelengths in the region 1040 A to 300 A which correspond to intense solar emission lines. The wavelength resolution, determined from the measured width of each of the spectral lines generated within the light sources, was in the range 0.04 to 0.1 A.

Flare X‐ray photochemistry of the E region ionosphere of Mars

“…In equation the incident X‐ray photon flux is taken from Figure between wavelength range of 1–8 Å at 5 min time resolution and energy bins of 0.2 Å. The photoabsorption and photoionization cross sections of CO 2 , N 2 , O 2 , O, and CO are taken from Pandya and Haider [], who compiled it in Tables A1 and A2, respectively, from different investigators [ Torr and Torr , ; Cairns and Samson , ; Cook et al , ; Lee et al , ; McCulloh , ; Iida et al , ; Watanabe et al , ]. The photoionization rate Q ( h , χ , t ) is obtained from primary photoelectron spectrum Q ( h , χ , E , t ) by integrating it over energy E .…”

“…In equation (7) the incident X-ray photon flux is taken from Figure 1 between wavelength range of 1-8 Å at 5 min time resolution and energy bins of 0.2 Å. The photoabsorption and photoionization cross sections of CO 2 , N 2 , O 2 , O, and CO are taken from Pandya and Haider [2014], who compiled it in Tables A1 and A2, respectively, from different investigators [Torr and Torr, 1979;Cairns and Samson, 1965;Cook et al, 1966;Lee et al, 1973;McCulloh, 1973;Iida et al, 1986;Watanabe et al, 1967]. The photoionization rate Q(h, χ, t) is obtained from primary photoelectron spectrum Q(h, χ, E, t) by integrating it over energy E. The time-dependent photoionization and photoelectron impact ionization rates are calculated for six flare days on 28 March and 6 April 2001, 17 and18 March and21 April 2003, and19 February 2005 at solar zenith angles 72°, 72°, 71°, 71°, 73°, and 73°respectively.…”

“…We have taken photoabsorption and photoionization cross sections from different laboratory measurements with uncertainties of 7-12% [cf. Cairns and Samson, 1965;Cook et al, 1966;Lee et al, 1973;McCulloh, 1973;Iida et al, 1986;Watanabe et al, 1967]. The theoretical cross sections for elastic and inelastic collisions are taken from Porter and Jump [1978] and Jackman et al [1977], respectively.…”

Numerical simulation of the effects of meteoroid ablation and solar EUV/X‐ray radiation in the dayside ionosphere of Mars: MGS/MEX observations

“…The photoabsorption and photoionization cross sections of N 2 , O 2 , and O are taken from Torr and Torr [1979]. The photoabsorption cross section of CO 2 for λ > 90 nm and in the range 48-60 nm are taken from Cairns and Samson [1965] and in the range 60-80 nm from Cook et al [1966]. In the wavelength range 18-48 nm, we have adopted the cross section measured by Lee et al [1973].…”

“…The photoionization cross section of CO 2 is taken from McCulloh [1973]. The photoabsorption and photoionization cross sections of CO have been taken from Cairns and Samson [1965]. The photoabsorption cross section of NO is adopted from Lida et al [1986].…”