Dynamical properties of quiescent prominence in He D3 5876 Angstrom line emission

Abstract

We have observed a quiescent prominence with the Coude spectrograph of Udaipur Solar Observatory during May 24-25, 1995. Analysis of two dimenstional spectroscopic data was carried out in order to obtain the line shifts and line widths of He D3 5876 Angstrom emission line. These quantities are used to study the dynamical properties of the observed prominence. The line-of -sight velocity distribution over the prominence follows a Gaussian distribution with half width of ±4.2 km/sec. However the line width over the prominence does not show a well defined distribution as does the line shift. Most of the line profiles have the half-width at half-maximum (HWHM) ranging from 180 mAngstrom to 280 mAngstrom. Assuming a typical prominence temperature of 8000k, we find turbulence velocity of around 4 km/s within the prominence. In this paper we present detailed results of the observations, and discuss their implications for the structure and dynamics of the prominence.