Schumann region

Schumanngebiet, n. Schumann region, schimd, pret. (of schinden) skinned. 

Leifson, S.W., Absorption spectra of some gases and vapors in the Schumann region. Astrophys J 63, 73, 1926. 

F is not yet as high as for atoms such as Cl, whose resonance transitions lie in the Schumann region of the vacuum ultraviolet. 

The vacuum ultraviolet is often known as the Schumann region in honor of the pioneer worker who first discovered a prism material and photographic plates which permitted work below 200 m/x to be done. 

Cheung A S C, Yoshino K, Freeman D E, Friedman R S, Dalgarno A and Parkinson W H 1989 The Schumann-Runge absorption-bands of 0 0 in the wavelength region 175-205 nm and spectroscopic constants of isotopic oxygen molecules J. Mol. Speotroso. 134 362-89... 

The X3 -—> B3X- transition is allowed and as seen in Figs. 4.2 and 4.3 results in an absorption in the 130-to 200-nrn region known as the Schumann-Runge system. The banded structure from about 175 to 200 nm corresponds to transitions from v" = 0 as well as v" = 1 (i.e., hot bands) of the ground X3S state to different vibrational levels of the upper state. 

Yoshino, K., J. R. Esmond, A. S.-C. Cheung, D. E. Freeman, and W. H. Parkinson, High Resolution Absorption Cross Sections in the Transmission Window Region of the Schumann-Runge Bands and Herzberg Continuum of 02, Planet. Space Sci.., 40, 185-192... 

Fig. V-12. Absorption coefficients of O, in the region 1100 to 2000 A. k is in units of atm em 0°C, base e. 1300 to 1700 A, Schumann-Runge continuum. 1750 to 1950 A, Schumann-Runge bands. From Watanabe c al. (1014), reprinted by permission. Copyright 1953 by the American Institute of Physics.

Fig. V-13. The absorption cross sections of the 02 continuum in the 1814 to 2350 A region, a is in units of 10"22 cm2 molec base e, at room temperature. The absorption cross sections are measured at minima between the well-separated rotational lines of the Schumann-Runge bands for X < 2025 A. a increases with pressure probably as a result of the formation of 04. The data are values at the low pressure limit. From Ogawa (755), reprinted by permission. Copyright 1971 by the American Institude of Physics.

The most recent studies have been carried out below the convergence limit of the Schumann-Runge band system at 1720 A. (76) and above the convergence limit at 1849 A. (95). Earlier studies in both regions (75) have been critically evaluated, (76) and it was concluded that the analytical procedures used were incorrect. The results obtained by Vol-man above the convergence limit are not substantially different from those reported by Smith and Napravnik below the convergence limit. 

Very weak absorption bands in the region 2500 to 3000 A correspond to the forbidden transition /1,ZU+-X 3Z9" (see selection rules 1-10.2). The band system is called the Herzberg 1 band. Second absorption bands in the region 1750 to 2000 A correspond to the B3Z -X3 transition and are called the Schumann-Rungc system. The region 1300 to 1750 A is continuous and is called the Schumann-Runge continuum. Below 1300 A numerous Rydberg transitions have been observed [Yoshino and Tanaka (1066)]. 

Popov " studied the oxidation of CO by atomic oxygen, which was produced by the photodissociation of O2 in the Schumann-Runge region (X < 1750 A). The rate of formation of CO2 varied linearly with [O2] in the pressure range of 0.02-0.12 torr. The rate increased with [CO] at low CO pressures (< 0.02 torr)... 

A number of authors, however, have represented forest or urban canopy layers by porous regions of distributed force (or drag) [206, 213, 217, 318, 320, 576, 662], The advantage of such an approach is that it permits inclusion of a canopy sublayer without the use of excessive and costly grid resolution. Yamada [662] and Shaw and Schumann [576] introduced the approach in order to add vegetation to meso-scale models of complex terrain. Jeram et al. [320] used the concept in 2d calculations for inviscid flow and constant eddy diffusivity flow estimates of the up and downwind penetration of flow within simple urban areas. 

At present, data on neuroanatomical alterations in ASD are still too scanty and not sufficiently robust to be convincingly linked to specific neurofunctional features in ASD. Brain regions showing more robust neuroanatomical alterations, in vivo or post-mortem, include the temporal cortex, the hippocampus, the amygdala and the cerebellum (reviewed in Courchesne et al., 2005 Keller and Persico, 2003 Palmen et al, 2004 Schumann and Amaral, 2006). 

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