Center for Astrophysics Research and Technologies Seminar Series
Giant Pulses and Heliospheric Faraday Rotation from the Crab Pulsar
Presented by Tarraneh Eftekhari, UNM
The Crab Pulsar occasionally emits single high intensity pulses. With flux densities thousands of times the average pulse flux density, these anomalous bursts are one of the brightest radio sources in the sky. While pulsar emission mechanisms remain elusive, several models have emerged in an attempt to explain the spurious giant pulse emission, including soliton collapse in strong plasma turbulence and the traversal of magnetohydrodynamic Alfven waves. These models have recently been shown to accord with observations at radio frequencies of 4 and 8 GHz. At the lower frequency regime, observations of giant pulses provide a useful probe of the interstellar medium and the turbulence of the surrounding pulsar magnetosphere. Wide-band studies of giant pulse phenomena are therefore crucial in constraining emission mechanisms. The Crab nebula is also an interesting source for heliospheric space weather studies as it both scintillates due to the solar wind and contains a polarized radio source for measuring faraday rotation. Observations of linearly polarized radio sources as viewed through the solar wind allow us to constrain the three dimensional structure of the coronal plasma and determine the magnitude of the magnetic field as a function of heliocentric distance. These studies are particularly helpful in determining the orientation of the magnetic field in a coronal mass ejection (CME) and thereby increasing the advance warning time on the geoeffectiveness of a CME.
2:00 pm, Thursday, March 19, 2015
PAIS-2540, PAIS
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