EDP Sciences
Free access
Volume 424, Number 1, September II 2004
Page(s) 317 - 323
Section Planets and planetary systems
DOI http://dx.doi.org/10.1051/0004-6361:20035623

A&A 424, 317-323 (2004)
DOI: 10.1051/0004-6361:20035623

The concentration of calcium ions and of free electrons in a meteor coma

P. B. Babadzhanov and G. I. Kokhirova

Institute of Astrophysics, Tajik Academy of Sciences, and Isaac Newton Institute of Chile, Tajikistan Branch, Bukhoro Str. 22, Dushanbe 734042, Tajikistan
    e-mail: [pbb;gulya]@ac.tajik.net

(Received 4 November 2003 / Accepted 23 April 2004 )

Prism spectra are studied of eight bright meteors, belonging to different showers and photographed by small cameras in the Gissar observatory of the Institute of Astrophysics, Tajik Academy of Sciences. Monochromatic light curves for the H and K spectral lines of the ionized calcium doublet are constructed and from the ratio of their intensities at selected points along the meteor trajectories the column   $N_{\rm CaII}$ and the volume  $n_{\rm CaII}$ concentrations of calcium ions are determined. The obtained values  $N_{\rm Ca II}=
10^{16}{-}10^{18}$  cm -2 and  $n_{\rm Ca II}=
10^{13}{-}10^{15}$  cm -3 are in good agreement with the estimates of calcium abundance obtained by other methods and confirm that there is almost full ionization of calcium atoms in meteor comae. The volume concentration of free electrons  $
n_{\rm e}=4\times 10^{13}$  cm -3 is defined, and the excitation temperature is calculated along the meteor paths.

Key words: meteors, meteoroids

© ESO 2004