Destabilization of EIC waves and heating of HPT ions

The electrostatic ion cyclotron (EIC) instability of hot plasma torus (HPT) particles in the auroral region due to field aligned current (FAC) has been studied. The value of FAC density JBB is estimated from the high time resolution magnetic field data of DE-1 spacecraft at altitudes ranging from 600 km to 2500 km during the magnetic storm of 21 Mar. 1990 during 0001-2000 hrs UT. The FAC destabilizes the EIC wave and the resultant electrostatic turbulence creates an anomalous resistivity. The current driven resistivity produces parallel electric field and high power dissipation. The growth rate of EIC wave decreases as the electron to ion temperature ratio Te/Ti increases for weak current density. The anomalous resistivity *h, parallel electric field EBB, power dissipation P and ion heating rate have been computed. It is found that these parameters decrease as Te/Ti increases. When the instability is almost shut off, the ion heating and transversely accelerated ions (TAI) are sharply reduced.