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Sodium And Potassiumvapor Faraday Filters Re-Visited: Theory And Applications, S. D. Harrell, C. Y. She, Tao Yuan, D. A. Krueger, H. Chen, S. Chen, Z. L. Hu

All Physics Faculty Publications

A complete theory describing the transmission of atomic vapor Faraday filters is developed. The dependence of the filter transmission on atomic density and external magnetic field strength, as well as the frequency dependence of transmission, are explained in physical terms. As examples, applications of the computed results to ongoing research to suppress sky background, thus allowing Na lidar operation under sunlit conditions, and to enable measurement of the density of mesospheric oxygen atoms are briefly discussed.

Prediction Of Saturation Effects On Potassium Lidar Returns, Joel R. Drake, Vincent B. Wickwar

Posters

The Atmospheric Lidar Observatory, on the Utah State University campus, will add a potassium lidar to its existing Rayleigh scatter system in the near future. The current system accurately measures temperatures from 40 km to 85 km in altitude.

Beginning at 80 km, a potassium layer forms due to the disintegration of meteors as they enter earth’s atmosphere. ALO plans to probe this layer using an alexandrite laser scanning a wavelength region near 770 nm, where potassium absorbs light. When the light is re-emitted, it can be measured in the same manner as scattered light in a Rayleigh lidar.

Usually, …

Evidence For Crystal-Field Splitting In Surface-Atom Photoemission From Potassium, G. K. Wertheim, D. Mark Riffe

All Physics Faculty Publications

Photoemission spectra from the shallow 3p_3/2 core levels of the surface atoms of metallic potassium exhibit the effects of a small but measurable crystal-field splitting of ∼38 meV. It manifests itself mainly as an apparent angle-dependent modulation of the spin-orbit splitting. This phenomenon may, in general, interfere with accurate determinations of surface-atom core-level shifts.

Coverage Dependence Of K Adsorption On Si(100)—2× 1 By Core-Level Photoemission, D. Mark Riffe, G. K. Wertheim, P. H. Citrin, J. E. Rowe

All Physics Faculty Publications

Using core-level photoemission, a coverage-dependent transition in the adsorption of K on Si(100)2×1 is observed. Below ∼0.25 monolayers, a single adsorption is occupied, the asymmetry of the Si-dimer reconstruction is enhanced, and no more than ∼0.05e is transferred from K to Si. Above this coverage, multiple sites are occupied, the dimer configuration becomes more symmetric, and the K overlayer becomes increasingly metallic. These findings resolve a number of conflicting studies of this system.

Decomposition Rates Of Aspen Bole And Branch Litter, W.E. Miller

Aspen Bibliography

No abstract provided.

Biomass And Nutrient Distribution In Aspen, Pine, And Spruce Stands On The Same Soil Type In Minnesota, David H. Alban, Donald A. Perala, Bryce E. Schlaegel

Aspen Bibliography

Vegetation and soils were sampled in adjacent 40-year-old stands of red pine (Pinus resinosa Ait.), jack pine (Pinus banksiana Lamb.), white spruce (Picea glauca (Moench.) Voss), and aspen (Populus tremuloides Michx., P. grandidentata Michx.) on a very fine sandy loam soil in north-central Minnesota. Total tree biomass was greatest for red pine followed by by aspen, spruce, and jack pine. Nutrient weights (N, P, K, Ca, Mg) in the trees were greatest in aspen followed generally by spruce, red pine, and jack pine. Particularly large proportions of biomass and nutrients were found in aspen bark and …

Potassium And Calcium Cycling By Eupterotegaeus Rostratus (Acari: Cryptostigmata), A. Carter, J.B. Cragg

Aspen Bibliography

Recent studies in an aspen woodland ecosystem in the Canadian Rockies have elucidated the biology of particular soil organisms and their roles in energy flow and, to a lesser extent, in chemical cycling.

Litter Fall And Chemical Cycling In An Aspen (Populus Tremuloides) Woodland Ecosystem In The Canadian Rockies, J.B. Cragg, A. Carter, C. Leischner, E.B. Peterson, G.N. Sykes

Aspen Bibliography

No abstract provided.

Effects Of Clear-Cutting On Nutrient Losses In Aspen Forests On Three Soil Types In Michigan, Curtis J. Richardson, Jeffrey A. Lund

Aspen Bibliography

No abstract provided.

Influence Of Growth Media, Temperatures, And Light Intensities On Aspen Root And Top Growth, Gerald F. Gifford

Aspen Bibliography

No abstract provided.