Fast Variations of Spectra of Comet Halley

Abstract

Results of the analysis of the Comet Halley spectrophotometry, which has been carried out by H.K. Nazarchuk in 1985 with the TV scanner of the 6-meter telescope (SAO, Russia) are presented. Time variations in the intensities of the CN, CH, C2 and NH2 bands were investigated using the series of spectra obtained in the spectral region λλ = 410 ÷ 510 nm. The auto-correlation functions for all the bands, the cross-correlation functions for C2 lines and their Fourier transformations are calculated to determine the frequencies and periods of the variations. A possibility is considered that high-amplitude fast variations of spectral lines in Comet Halley are caused by solar flares. The daily numbers of solar spots and proton fluxes with energies of more then 1 MeV are compared with the spectral variations of these lines. It is shown that in the observation periods the comet was projected onto an active region of the Sun, but, among all the kinds of solar activity, mainly the solar proton flux with energies less than 4 MeV coincides in time with fast intensity variations in the spectral lines. An algorithm of cross-correlation analysis of discrete sampling series with gaps is built, and average cross-correlation coefficients are calculated.