| Abstract : | Pulsars are one of the most enigmatic objects in the universe, whose physical appearance is inferred from the observed or physical characteristics of rapidly spinning neutron stars, possessing a hugely powerful magnetic field to the order of ~ 10^8 - 10^(12) Gauss. In each epoch of rotation, radio flashes from pulsars pass our line of sight and we receive a series of periodic signals similar to the lighthouse. Pulsar's paradigm is quite rich and from the last 50 years after its discovery, it attained an unprecedented level of success and its application got diversified into different streams such as gravitational wave, nuclear physics so on. However, in this thesis talk, I would try to mainly constrain some of the theoretical aspects in the framework of coherent curvature radiation to ponder some thoughts towards generating integrated pulse profile, originating from pulsar magnetosphere. Most of the literature recognizes pulsars radio emission mechanism to be a broadband process and coherent as well, as inferred from very high brightness temperature in radio band ~10^(25) K. However emission mechanism is a multi-stage process which is determined by both radio emission geometry and kinematics of electron-positron pair plasma. Several instabilities such as two-stream instability probably act in the pulsar magnetosphere to generate Langmuir waves and finally, these waves get converted to transverse escaping modes by some complicated propagation effect in the quasi tangential zone. Nevertheless, the main objective is to include the plasma bunch topology and solve the emission geometry, and then integrate the stokes parameter over the emission region with a modulation effect to get the net flux. Here I tried to show some diverse polarization profiles associated with pulsar radio emission and predicted brightness temperature for typical physical parameters of pulsars from theoretical simulation, which shows reasonably good agreement with existing data.
Reference
1. Tridib Roy Gangadhara 2019 ApJ 156 148
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