Prof. Poonam Chandra

The terminology pulsar is traditionally used for pulse emitting neutron stars. However, there is a class of stars that emit periodic radio pulses, but are still living in the main-sequence. These stars are hence named as ‘main-sequence pulsar’s (MSPs). All of the MSPs are magnetic early-type stars which are characterized by the presence of large-scale, highly ordered and stable surface magnetic fields. The mechanism by which they produce radio pulses is the electron cyclotron maser emission (ECME), which is also the mechanism behind the Earth’s auroral kilometric emission. In my talk, I will describe the unique characteristics of MSPs that set them apart from other ECME emitting objects. The highlight of my talk will be the different information which one can extract about the host star from the observation of ECME. This includes (but not limited to) inference of rotation period evolution, and estimation of plasma density and distribution in the stellar magnetosphere. In addition, I will also talk about radio flares that we have recently observed from a main-sequence pulsar at low frequencies. I will discuss possible source of these flares and their implication about the magnetic field-stellar wind interaction.