DETECTION OF SHORT-PERIOD CORONAL OSCILLATIONS DURING THE TOTAL SOLARECLIPSE OF 24 OCTOBER, 1995

An experiment to search for short-period oscillations in the solar cor ona was conducted during the total solar eclipse of 1995 October 24 at Kalpi, India. The intensity in the continuum, centred around 5500 Ang strom and with a passband having a half-width of 240 Angstrom, was rec orded at a counting rate of 20 Hz using a thermoelectric-liquid cooled photomultiplier. The power-spectrum analysis of the data reveals that most of the power is contained in 6 frequencies below 0.2 Hz. A least -square analysis gives the periods of the 6 frequency components to be 56.5, 19.5, 13.5, 8.0, 6.1, and 5.3 a. These oscillations are found t o be sinusoidal, and their amplitudes are found to lie in the range 0. 2-1.3% of the coronal brightness. Assuming these oscillations to be fa st magnetosonic modes, the calculations indicate the availability of e nough flux for the heating of the active regions in the solar corona.