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Full-Text Articles in Physical Sciences and Mathematics
Temperature Tides Across The Mid-Latitude Summer Turbopause Measured By A Sodium Lidar And Mighti/Icon, Tao Yuan, M. H. Stevens, C. R. Englert, T. J. Immel
Temperature Tides Across The Mid-Latitude Summer Turbopause Measured By A Sodium Lidar And Mighti/Icon, Tao Yuan, M. H. Stevens, C. R. Englert, T. J. Immel
All Physics Faculty Publications
Local full diurnal coverage of temperature variations across the turbopause (∼90–115 km altitude) is achieved by combining the nocturnal observations of a Sodium (Na) Doppler lidar on the Utah State University (USU) campus (41.7°N, 248.2°E) and NASA Michelson interferometer for global high-resolution thermospheric imaging (MIGHTI)/Ionospheric connection explorer (ICON) daytime observations made in the same vicinity. In this study, utilizing this hybrid data set during summer 2020 between June 12th and July 15th, we retrieve the temperature signatures of diurnal and semidiurnal tides in this region. The tidal amplitudes of both components have similar vertical variation with increasing altitude: less than …
A Global Climatology Of The Mesospheric Sodium Layerfrom Gomos Data During The 2002-2008 Period, D. F. Fussen, F. Vanhellemont, C. T'Etart, N. Mateshvili, E. Dekemper, N. Loodts, C. Bingen, E. Kyrola, J. Tamminen, V. Sofieva, A. Hauchecorne, F. Dalaudier, J. L. Bertaux, G. Barrot, L. Blanot, O. Fanton D'Andon, T. Fehr, L. Saavedra, Tao Yuan, C. Y. She
A Global Climatology Of The Mesospheric Sodium Layerfrom Gomos Data During The 2002-2008 Period, D. F. Fussen, F. Vanhellemont, C. T'Etart, N. Mateshvili, E. Dekemper, N. Loodts, C. Bingen, E. Kyrola, J. Tamminen, V. Sofieva, A. Hauchecorne, F. Dalaudier, J. L. Bertaux, G. Barrot, L. Blanot, O. Fanton D'Andon, T. Fehr, L. Saavedra, Tao Yuan, C. Y. She
All Physics Faculty Publications
This paper presents a climatology of the mesospheric sodium layer built from the processing of 7 years of GOMOS data. With respect to preliminary results already published for the year 2003, a more careful analysis was applied to the averaging of occultations inside the climatological bins (10° in latitude-1 month). Also, the slant path absorption lines of the Na doublet around 589 nm shows evidence of partial saturation that was responsible for an underestimation of the Na concentration in our previous results. The sodium climatology has been validated with respect to the Fort Collins lidar measurements and, to a lesser …
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
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
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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.
Concurrent Ohimager And Sodium Temperature/Wind Lidar Observation Of Localized Ripples Over Northern Colorado, L. Tao, C. Y. She, B. P. Williams, Tao Yuan, R. L. Collins, L. Kieffabar, A. Peterson
Concurrent Ohimager And Sodium Temperature/Wind Lidar Observation Of Localized Ripples Over Northern Colorado, L. Tao, C. Y. She, B. P. Williams, Tao Yuan, R. L. Collins, L. Kieffabar, A. Peterson
All Physics Faculty Publications
On 3 and 5 September 2002 the OH all-sky imager at Platteville, Colorado (40.2°N, 104.7°W), observed small-scale, wavelike patterns (known as ripples), with horizontal wavelengths of ∼9 km and ∼7 km and lifetimes of ∼9 min and ∼15 min, respectively. The Colorado State University sodium lidar at nearby Fort Collins, Colorado (40.6°N, 105°W), also made concurrent observations of temperature and zonal and meridional winds, which allowed us to determine the nature of the ripples observed. Our observations suggest that the 3 September ripple was induced by a convective instability located at 87.5 km and the 5 September ripple was induced …
Concurrent Oh Imager And Sodiumtemperature/Wind Lidar Observation Of A Mesopause Region Undular Bore Event Over Fort Collins/Platteville, Co, C. Y. She, T. Li, B. P. Williams, Tao Yuan, R. H. Picard
Concurrent Oh Imager And Sodiumtemperature/Wind Lidar Observation Of A Mesopause Region Undular Bore Event Over Fort Collins/Platteville, Co, C. Y. She, T. Li, B. P. Williams, Tao Yuan, R. H. Picard
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We reported the observation of a mesospheric front with the properties of an undular bore by an OH imager, over the Fort Collins/Platteville area on 6/7 October 2002. Unlike the earlier bore observations, a Na lidar capable of measuring mesopause region temperature, zonal, and meridional winds was in operation concurrently. The lidar data confirm, for the first time, the existence of a collocated temperature inversion layer to serve as the ducting region for bore propagation, as required by the simple theory proposed by Dewan and Picard 6 years ago. In addition, the lidar data in principle provide sufficient information for …
Enhanced Vibrational Broadening Of Core-Level Photoemission From The Surface Of Na(110), D. Mark Riffe, G. K. Wertheim, P. H. Citrin
Enhanced Vibrational Broadening Of Core-Level Photoemission From The Surface Of Na(110), D. Mark Riffe, G. K. Wertheim, P. H. Citrin
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High-resolution temperature-dependent photoemission data from Na 2p core levels reveal substantially larger phonon broadening in the first atomic layer of Na(110) than in the bulk. We show that the enhanced width is due primarily to the excitation of relatively soft phonon modes perpendicular to the surface. Soft surface-phonon modes also account for previously reported but uninterpreted broadening of transition-metal surface-atom core levels.