Study of pulsar emission mechanism using GMRT
Owing to its high sensitivity and extensive frequency coverage, the GMRT allows study of individual pulses of pulsars. Individual pulses show a variety of structures over a range of timescales, which reveals a wealth of information about the emission process. These pulses have been observed to consist of one or more subpulses, which further show quasi-periodic intensity fluctuations known as microstructures. Furthermore, the pulse intensity often drops to a low value for a few pulses and then abruptly returns to normal. This phenomenon, known as nulling, is inversely correlated with the age of the pulsar. In this project, we try to explain the underlying emission mechanism through a detailed analysis of individual pulse data from several pulsars. The raw data obtained from the GMRT is processed by making use of the software package GPTool. The output from GPTool is analysed to obtain the intensity profile for individual pulses which are then scanned for the presence of microstructures and pulse nulling. The analysis is performed for several normal pulsars, as well as a few millisecond pulsars which can be observed using the GMRT.
Keywords: microstructure, nulling, GPTool, millisecond pulsars