A first approach to model the low-frequency wave activity in the plasmasphere

International audienceA comprehensive empirical model of waves is developed in the objective to simulate wave-particle interactions involved in the loss and acceleration of radiation belt electrons. Three years of measured magnetic wave field components from the Plasma Wave Instrument on board the DE-1 satellite are used to model the amplitude spectral density of the magnetic wave field of each type of emission observed in the equatorial regions of the plasmasphere: VLF transmitter emissions, chorus emissions, plasmaspheric hiss emissions and equatorial emissions below ~ 200 Hz. Each model is a function of the wave frequency f , the MLT, L and Mlat parameters, and the Kp values. The performances of the plasmaspheric hiss and chorus models are tested on amplitude spectra recorded on board the OGO-5 and GEOS-1 satellites

Seabed propagation of ULF/ELF electromagnetic fields from harmonic dipole sources located on the seafloor

The amplitudes of the quasi-static electromagnetic fields generated at points on the seafloor by harmonic dipole sources (vertically directed magnetic dipoles, horizontally directed magnetic dipoles, vertically directed electric dipoles, and horizontally directed electric dipoles) also located on the seafloor are computed using a numerical integration technique. The primary purpose of these computations is to obtain field amplitudes that can be used in undersea communication studies. An important secondary purpose is to examine the enhancements of the fields produced at moderate to large distances by the presence of the relatively less conducting seafloor, as compared with the fields produced at the same distances in a sea of infinite extent, for frequencies in the ULF/ELF bands (frequencies less than 3 kHz). These latter enhancements can be surprisingly large, with increases of 4 orders of magnitude or more being typical at distances of 20 seawater skin depths

Human fascioliasis

ABSTRACTFasciola hepatica, a zoonotic liver fluke, can also cause disease in humans. Common symptoms are epigastric pain, upper abdominal pain and malaise. Fever and arthralgia are common in acute fascioliasis. Eosinophilia is the predominant laboratory finding, especially in patients with the acute form of the disease. Diagnosis and treatment is not easy, as physicians rarely encounter this disease, and effective drugs are not available in many countries. Human fascioliasis may be underestimated. Patients with eosinophilia and abdominal pain should be evaluated for F. hepatica infestation by parasitological, radiological and serological tests

Probe of extra dimensions in gamma q->gamma q at the LHC

We have examined TeV scale effects of extra spatial dimensions through the processes gamma q-> gamma q where q=u,d,c,s,b, anti-u, anti-d, anti-c, anti-s, anti-b. These processes have been treated in a photon-proton collision via the main reaction pp-> p gamma p-> p gamma qX at the LHC. We have employed equivalent photon approximation for incoming photon beams and performed statistical analysis for various forward detector acceptances.Comment: 17 pages, 5 figure

Anthropogenic Space Weather

Anthropogenic effects on the space environment started in the late 19th century and reached their peak in the 1960s when high-altitude nuclear explosions were carried out by the USA and the Soviet Union. These explosions created artificial radiation belts near Earth that resulted in major damages to several satellites. Another, unexpected impact of the high-altitude nuclear tests was the electromagnetic pulse (EMP) that can have devastating effects over a large geographic area (as large as the continental United States). Other anthropogenic impacts on the space environment include chemical release ex- periments, high-frequency wave heating of the ionosphere and the interaction of VLF waves with the radiation belts. This paper reviews the fundamental physical process behind these phenomena and discusses the observations of their impacts.Comment: 71 pages, 35 figure