Magnetic field reversal

Bob takes the magnet from Mr. Plex s claws. The Sun s magnetic field extends throughout the solar system. It s quite complicated because of the Sun s rotation and the convection of electrically charged particles in the Sun s hot gases. The magnetic field reverses every 11 years, right after the time when the sunspot number peaks. ... 

Figure 9 Middle-Late Miocene timescale indicating relationships among fossil-based, radiometric and magnetic field reversal chronometries. Note that three zone successions based on developments among planktic foraminiferans are indicated. These three different zonal sequences reflect hiogeographic provincialism in these organisms. That provincialism resulted from ocean surface-water temperature differences. The calcareous nannoplankton or coccohthophore zonal scales of two different specialists are shown. These reflect different...

Employing the 1 TW GAMBLE-2 pulsed power generator at NRL to power a reflex-tetrode proton source, Kapetanakos et al. have recently reported the achievement of transient magnetic field reversal for a period 30 nsec. In this experiment an annular 60 nsec, 200 kA proton beam is bunched by a ramped voltage pulse and injected through a magnetic cusp which causes the beam to rotate. 

Levy M, Sarachik MP (1989) Measurement of the Hall coefficient using van der Pauw method without magnetic field reversal. Rev Sci Instrum 60 1342... 

Now the system is thennally insulated and the magnetic field is decreased to zero in this adiabatic, essentially reversible (isentropic) process, the temperature necessarily decreases since... 

Fig. 7. Thermomagnetic recording, (a) A focused laser beam generates a thermal profile in the magnetic layer, (b) The coercive force in the layer is reduced and its magnetisation can be reversed by a small magnetic field, here 30 kA/m. At room temperature, the coercive force is high and the written domains are...

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