Study of Duct Characteristics Deduced from Low Latitude Ground Observations of Day-Time Whistler at Jammu

Abstract

<p class="MsoNormal"> <span lang="EN-US" style="font-family:Verdana;">Propagation characteristics of low latitude whistler duct characteristics have been investigated based on day-time measurements at Jammu. The morphogical characteristics of low latitude whistlers are discussed and compared with characteristics of middle and high latitude whistlers. The Max</span><span lang="EN-US" style="font-family:Verdana;">. </span><span lang="EN-US"><span style="font-family:Verdana;">electron density (</span><i><span style="font-family:Verdana;">N</span>_{<span style="font-family:Verdana;">m</span>}</i><span style="font-family:Verdana;">) at the height of the ionosphere obtained from whistler dispersion comes out to be higher than that of the background which is in accordance with the characteristics of whistler duct. The equivalent width is found to be close to the satellite observations and the characteristics of whistler duct in low latitude ionosphere are similar to those in middle and high latitude ionosphere. The width of ducts estimated from the diffuseness of the whistler track observed during magnetic storm is found to lie in the range of 50 -</span></span><span lang="EN-US"> </span><span lang="EN-US" style="font-family:Verdana;">200 Km.</span> </p

A new angle for probing field‐aligned irregularities with the Murchison Widefield Array

“…Numerical studies suggest that tubular structures can also be effective waveguides [ Smith , ; Platt and Dyson , ]. The existence of tubular structures with inferred widths of 10–100 km has been established through satellite in situ measurements [ Angerami , ; Sonwalkar et al , ; Décréau et al , ], satellite remote sensing [ Fung et al , ; Darrouzet et al , ; Woodroffe et al , ], ground‐based whistler spectrograms [ Hayakawa and Tanaka , ; Singh et al , ; Altaf and Ahmad , ], and ground‐based radio interferometric arrays [ Jacobson and Erickson , ; Hoogeveen and Jacobson , ; Helmboldt and Intema , ]. Recent interferometric observations support the idea that tubular FAIs may in some instances be confined to a narrow sheet‐like layer on a single magnetic shell [ Loi et al , , ].…”