The calibration and initial results of the HeI D3 line flash spectrum obtained during the 2008 total solar eclipse

The flash spectra in the Hel D3 line were obtained during the 2008 total solar eclipse. This paper describes the instrument and the calibration of the obtained flash spectrum, and presents our initial results. The average integrated intensity is E(ave) = 8.13 x 10(13) erg.cm(-1).s(-1).ster(-1) at h = 1100 km, which confirms that the Hel D3 emission is negatively correlated with the solar activity. The surface brightness reaches a maximum of F(ave) = 8.25 x 10(5) erg.cm(-2).s(-1).ster(-1) at about h approximate to (1290 +/- 75) km and then decreases exponentially with height when h > 1800 km with an exponential index beta = 1.63 x 10(-8) cm(-1).