A Yb fiber amplifier based Doppler He lidar for upper atmospheric research
Abstract
Upper thermospheric and exospheric temperatures (Te) have uniquely related the density at altitude to the solar cycle (F10.7). Discoveries cited in recent analysis suggest that O loss in the mesosphere where chemical loss occurs, related to transport velocities (kzz), affect O densities, as well as the total amount of O in the upper mesosphere and lower thermosphere (MLT) system vs. solar cycle. Measurements of the actual ionosphere-thermosphere (IT) temperatures vs solar cycle will contribute to understanding the more complex relationships. A Doppler wind-temperature resonance fluorescence lidar would allow a direct measurement of neutral winds and temperatures in the thermosphere from 300-1000 km similar to metal resonance lidars that have been used to probe the mesosphere and lower thermosphere (80-100km) region [1,2]. Metastable helium (He) produced in the thermosphere and exosphere is a candidate for a resonance fluorescence lidar as described by Gerrard et al. [3]. Development of a He lidar is becoming a reality with recent developments in semiconductor lasers, high power rare-earth-doped fiber amplifiers, and compound semiconductor photon detectors. The reality of a He resonance fluorescence lidar is in reach. It is anticipated that with a sufficient signal to noise ratio (SNR), a thermosphere lidar would be capable of providing
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Mar 07, 2023
- Source ID
- FA95502110298
Entities
People
- Peter D. Dragic
Organizations
- Air Force Office of Scientific Research
- United States Air Force
- University of Illinois Urbana–Champaign