Determination of Physical and Radiant Meteor Properties Using PFISR Interferometry Measurements of Head Echoes

Abstract

Over the past decade, High Power and Large Aperture (HPLA) radars have been widely utilized for the study of sub-millimeter extraterrestrial particles via the detection of the meteor head-echo. These observations have been a successful tool in the study of the sporadic meteor background, however, they have been limited by the lack of precise knowledge of the particle’s location within the radar beam and its absolute trajectory and velocity. This limitation prevents for example the accurate determination of the meteors radiant and orbit. Interferometry measurements of the head-echo has been proven to be a detection technique that satisfies this need. Unfortunately very few radars are capable of performing them. We have developed a methodology which takes advantage of the multi-receiving capabilities of the 450 MHz Poker Flat Incoherent Scatter Radar (PFISR) enabling us to utilize the phased array of crossed-dipoles as an interferometer. This new PFISR capability allows us to determine the instantaneous position of meteors within the radar beam. This enables us to determine absolute velocities and ultimately meteor radiant and orbit around the Sun. In this work, we present initial results from 9 h of observations during which 142 particles were individually detected by the three different receiving channels simultaneously. For these meteors absolute velocities were obtained and meteor dynamical, physical and radiant properties were derived.