Abstract Details
| Name: Bhal Chandra Joshi Affiliation: NCRA-TIFR Conference ID: ASI2018_611 Title : Using wide-band multi-frequency capabilities of upgraded-GMRT for single pulse studies and pulsar timing Authors and Co-Authors : Bhal Chandra Joshi NCRA-TIFR, Pune Abstract Type : Poster Abstract Category : Stars,ISM and the Galaxy Abstract : The seamless frequency coverage from 250 to 1500 MHz, distributed over three bands (Band 3,4 and 5), together with provision of four 400 MHz beams and the sub-array nature of the instrument, provides a unique instrument in the world for simultaneous multi-frequency low frequency single pulse studies of radio pulsars, which are bright at these frequency bands due to their steep spectra. Such studies are important to unify the diversity of single pulse phenomena, such as sub-pulse drifting, pulse nulling and sub-pulse related profile mode changes and provide constraints to pulsar emission physics from multiple point of views. Sub-pulse drift probes the electric field in the polar gaps, whereas sub-pulse drift related profile modes, when studied at multiple frequencies simultaneously, probe the magnetospheric configurations and radio emission heights and geometry. Pulsars, such as PSR B0031--07, J1822--2256 and B2319+60, show multiple distinct drift modes and drift mode related profiles (Joshi 2013, Gajjar et al. 2014, Naidu et al. 2017, Joshi et al. 2018, Joshi and Padlekar 2018). Simultaneous multi-frequency observations with Band 3, 4 and 5 of upgraded GMRT for such pulsars are useful to separate beam geometry from emission dynamics. In this presentation, I describe the unique capabilities of uGMRT for such studies and illustrate these capabilities from our recent work based on such observations in Cycle 32 of uGMRT. I will also briefly refer to the capabilities of both legacy GMRT and uGMRT along-with Ooty Radio Telescope for multi-frequency simultaneous high precision timing observations of 9 millisecond pulsars as part of Indian Pulsar Timing Array experiment (InPTA) for detection of nanoHertz gravitational waves and future prospects for such studies. |