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Bhaswati Bhattacharyya, Yashwant Gupta, Yogesh Maan, Visweshwar Ram Marthi, Dipanjan Mitra, Jayanta Roy, M. A. Krishnakumar, Bhal Chandra Joshi, Post-docs and Ph.D. students: S. Kudale, A. Ghosh, A. Kumar, J. Salal, S. Kumari, U. Panda, S. Bhattacharyya, K. Bane, Former members: Sk. Minhajur Rahaman, Shubham Singh, Shyam Sunder

Pulsars are rapidly rotating neutron stars that emit beams of radio radiation from their magnetic poles, at low frequencies, ideally suited for the ORT and the GMRT. NCRA-TIFR members are involved in blind and targeted searches that have already resulted in a number of discoveries of new and interesting pulsars. Other research areas, aimed at understanding the origin of pulsar radio emission, include pulsar timing studies, studies of their emission properties such as the evolution of pulse profiles, nulling and mode changing phenomena, as well as scattering and dispersion of pulsar signals by the ISM. Theoretical attempts are also being made to find evolutionary pathways linking different classes of neutron stars.

Transients are astronomical objects that show sudden, dramatic changes in their intensity on short timescales, ranging from seconds, days, weeks, months to several years. Transient phenomenon usually represents extremes of gravity, magnetic fields, velocity, temperature, pressure, and density. In terms of duration, transients phenomenon can be classified into two classes, transients with long time variability (min-days) and short term (sub-second variability) transients. Transients in radio bands are mainly dominated by three kinds of emission mechanisms. Slow transients majorly emit via incoherent synchrotron mechanism and are limited by the brightness temperature. These events are mainly associated with explosive events, such as Gamma Ray Bursts, supernovae, X-ray binaries, tidal disruption events etc. In addition, novae and symbiotic stars show slow variability and are dominated by thermal emission. Fast transients are usually associated with coherent emission and show relatively fast variability, high brightness temperature and often show high polarization associated with them, such as Fast Radio bursts, flare stars etc.

Radio wavelengths, especially in commensal survey mode, are particularly well suited for uncovering the complex transient phenomena. This is because observations at radio wavelengths may suffer less obscuration than in other bands. At the same time, multi waveband information often provides critical source classification rapidly than possible with only radio band data. Therefore, multi waveband observational efforts are the key to the progress of transients astronomy. The new capabilities of the GMRT correlator are being used to search for new types of transients. Multi-waveband studies of supernovae and gamma ray bursts are also being carried out. In particular, radio and X-ray observations of supernovae and gamma ray bursts have been used to trace the density and temperature of the surrounding medium, along with the shock conditions that accompany such events.