Observations of persistent Leonid meteor trails 2. Photometry and numerical modeling

During the 1998 Leonid meteor shower, multi-instrument observations of pers istent meteor trains were made from the Starfire Optical Range on Kirtland Air Force Base, New Mexico, and from a secondary site in nearby Placitas, N ew Mexico. The University of Illinois Na resonance lidar measured the Na de nsity and temperature in the trains, while various cameras captured images and videos of the trains, some of which were observed to persist for more t han 30 min. The Na density measurements allow the contribution of Na airglo w to the observed train luminescence to be quantified for the first time. T o do this, persistent train luminescence is numerically modeled. Cylindrica l symmetry is assumed, and observed values of the Na density, temperature, and diffusivity are used. It is found that the expected Na luminosity is co nsistent with narrowband CCD all-sky camera observations, but that these em issions can contribute only a small fraction of the total light observed in a 0.5-1 mu bandwidth. Other potential luminosity sources are examined, in particular, light resulting from the possible excitation of monoxides of me teoric metals (particularly FeO) and O-2(b(1)Sigma (+)(g)) during reactions between atmospheric oxygen species and meteoric metals. It is found that t he total luminosity of these combined processes falls somewhat short of exp laining the observed brightness, and thus additional luminosity sources sti ll are needed. In addition, the brightness distribution, the so-called holl ow cylinder effect, remains unexplained.