Blar i forfatter "Oppenheim, Meers"

Viser treff 1-3 av 3

    • Millstone Hill ISR Measurements of Small Aspect Angle Spectra 

      Longley, William; Erickson, Philip J.; Vierinen, Juha; Oppenheim, Meers; Lind, Frank David; Dimant, Yakov (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-05-04)
      The Millstone Hill incoherent scatter (IS) radar is used to measure spectra close to perpendicular to the Earth's magnetic field, and the data are fit to three different forward models to estimate ionospheric temperatures. IS spectra measured close to perpendicular to the magnetic field are heavily influenced by Coulomb collisions, and the temperature estimates are sensitive to the collision operator ...

    • Solar Flare Effects on 150-km Echoes Observed Over Jicamarca: WACCM-X Simulations 

      Pedatella, Nick; Chau, Jorge Luis; Vierinen, Juha; Qian, L; Reyes, Pablo; Kudeki, Erhan; Lehmacher, G; Oppenheim, Meers (Journal article; Tidsskriftartikkel, 2019-09-11)
      Jicamarca Radio Observatory observations and Whole Atmosphere Community Climate Model with thermosphere‐ionosphere eXtension (WACCM‐X) simulations are used to investigate the effects of the September 7, 2005 X‐17 solar flare on 150‐km echoes, electron densities, and vertical plasma drifts. The solar flare produces a remarkably similar response in the observed 150‐km echoes and simulated electron ...

    • Solved and unsolved riddles about low-latitude daytime valley region plasma waves and 150-km echoes 

      Chau, Jorge Luis; Longley, William; Reyes, Pablo; Pedatella, Nick; Otsuka, Yuichi; Stolle, Claudia; Liu, Huixin; Vierinen, Juha; Milla, Marco; Hysell, David L.; Oppenheim, Meers; Patra, A.; Lehmacher, G; Kudeki, Erhan (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-02-27)
      The Earth’s atmosphere near both the geographic and magnetic equators and at altitudes between 120 and 200 km is called the low-latitude valley region (LLVR) and is among the least understood regions of the ionosphere/thermosphere due to its complex interplay of neutral dynamics, electrodynamics, and photochemistry. Radar studies of the region have revealed puzzling daytime echoes scattered from ...