Scintillation

About: Scintillation is a research topic. Over the lifetime, 14022 publications have been published within this topic receiving 187694 citations.

The height of scintillation-producing ionospheric irregularities in temperate latitudes

Abstract: The heights of ionospheric irregularities responsible for radio satellite scintillation were directly measured by using spaced receivers on 130 passages of Transit 4A. Observed irregularity heights vary from 90 to 800 km. Most of the irregularities were in the F region between 300- and 400-km height. A significant amount of scintillation was caused by irregularities in the E region near 100-km height. E-region scintillation is most probable at midday, F-region scintillation at midnight. Strong positive correlation was found between both E- and F-region scintillation and sporadic-E and spread-F conditions on ionograms. F-region irregularity heights increased, on the average, toward the north. Most individual regions of irregularities were found to have little change of height with latitude. About ⅓ of the passes showed gradual or abrupt height changes, increasing to the north or south with equal probability, in some part of the pass. Height gradients were seldom uniform for distances of more than 50–100 km.

YAlO3: Ce scintillators: application for X- and soft γ-ray detection

Abstract: The possibility of applying YAlO3:Ce scintillation crystals for X-ray and low energy γ-ray detection has been investigated. Examples of scintillation spectra obtained with various irradiation sources are given. The crystal thickness has been optimized.

Equatorial spread F irregularity characteristics over São Luís, Brazil, using VHF radar and GPS scintillation techniques

Abstract: [1] Multitechnique observations may considerably improve our understanding of factors responsible for the generation, growth, and dynamics of the destabilized nighttime equatorial F region plasma irregularities. In order to investigate the dynamics of plasma density irregularities of different scale sizes, a campaign of observations was conducted during 11–20 November 2001 at the Brazilian magnetic equatorial station Sao Luis (2.57°S, 44.21°W, dip latitude 1.73°S). We carried out observations using VHF coherent backscatter radar, two spaced GPS-based scintillation monitors, and one digisonde. Range type spread F on ionograms and radar plume signatures on range-time-intensity maps of the VHF radar started at similar times. In order to compare GPS L1 (1.575 GHz) scintillations and radar plumes we used the scintillation S4 index computed for the signal transmitted by the highest elevation satellite. GPS scintillations were not observed during the initial bottom-type layer shown by the radar; however, stronger scintillations (higher S4 values) were observed concurrently to stronger radar echoes. Although the time duration of GPS scintillation is longer than the duration of the plumes observed by the radar, ionosonde spread F is still much longer than scintillation occurrence, confirming that smaller scale-size irregularities decay faster. Zonal and vertical velocities of 5-m irregularities measured by the radar were analyzed jointly with the apparent zonal velocity of ∼400-m irregularities measured by the spaced-receiver scintillation method. Larger values of the zonal velocity measured by the scintillation technique were found during the explosive growth phase of radar plumes associated with large values of vertical drifts measured by the radar.