Scintillation Studies Using Radio Telescope at Rajkot

The phenomenon of interplanetary scintillation is an effective tool to study the solar activity. The technique involves observation of radio signals from a distant compact source propagating through the IPM. These waves from the radio source are scattering by density irregularities in the interplanetary plasma to produce a two dimensional intensity pattern on the ground. The pattern moves because of the relative velocity of the solar wind and the earth and is observed as intensity scintillations by a radio telescope. The study of IPS activity is also of practical importance, as major solar activity often results in geomagnetic disturbances which disrupt radio communication and pose radiation hazards to astronauts on space missions. For these reasons it is important to understand interplanetary activity over all possible scales and study its relation to the solar and geomagnetic activity. The existing IPS observations, however, have been more suited to study long time scale interplanetary activity. The radio telescope at Rajkot used for the present investigations consists of a full wave dipole antenna array, correlation receiver, and analogue and digital data recording devices.