Auroral sporadic-E ionization

Plasma Lines in the Auroral E Layer

Hf-pump-induced Parametric Instabilities in the Auroral E-region

In November 1999 the EISCAT high-power, high-frequency (HF) facility located near Tromsø, Norway, was used to create artificial plasma turbulence in the ionosphere. During the experiment the EISCAT 224 MHz radar and sometimes the 931 MHz radar were used to obtain measurements of incoherent scatter ion and plasma lines, and artificially enhanced spectra of E-region plasma waves were measured for...

Sporadic hepatitis E in southern India.

The definite existence of a second enterically transmitted hepatitis virus (non-A) was recognized in 1980 and retrospectively diagnosed to have caused the 1955 Delhi epidemic (KHUROO, 1980; TICEHURST, 1995). The name hepatitis E virus (HEV) was proposed for the agent in 1988; bv the vear 1990 its identitv was firmlv established when its genomic structure was elucidated (F&YES et al.. 1990). Unt...

The lunar tide in sporadic E

It seems that the wind shear theory is accepted for the explanation of sporadic E at mid and low latitudes. Some examples from Arecibo are displayed to show this. The e€ect of lunar tides should then modify the wind-shear theory in a manner that yields the observed features of the lunar tide in the critical frequency foEs and the height h¢Es of the sporadic E. This is shown to imply that the ph...

Luminosity variations in several parallel auroral arcs before auroral breakup

Variation of the luminosity in two parallel auroral arcs before auroral breakup has been studied by using digitised TV-data with high temporal and spatial resolution. The intervals when a new arc appears near already existing one were chosen for analysis. It is shown, for all cases, that the appearance of a new arc is accompanied by fading or disappearance of another arc. We have named these ev...