The Aragats Space-Environmental Center provides monitoring of different species of secondary cosmic rays at two altitudes and with different energy thresholds. One-minute data is available on-line ...from
http://crdlx5.yerphi.am/DVIN/index2.php. We present description of the main monitors along with data acquisition electronics. Also we demonstrate the sensitivity of the different species of secondary cosmic ray flux to geophysical conditions, taking as examples the extremely violent events of October–November 2003. We introduce correlation analysis of the different components of registered time-series as a new tool for the classification of the geoeffective (events on earth affected by solar activity) events and for the forecasting of the severity of the upcoming geomagnetic storm.
An attempt has been made to show, as a result of careful analysis of IUE spectral recordings for a group of planetary nebulae, that the existence of one pseudoresonance line 1300 (Si III) is without ...doubt at least in spectra of three planetary nebulae: NGC 2610, NGC 3587, and NGC 6891. The presence of this line in the spectra of the other three planetary nebulae, NGC 6210, IC 3568, and IC 4776, seems to be probable. Also analyzed were the role of interstellar selective absorption; the blending effect by the resonance lines of Si II, O I, and S I in the formation of the pseudoresonance line 1300 (Si III); and the possibility of formation of this line in the photosphere of the central star of the nebula. (Author)
IUE 200-300-nm spectroscopic observations of CN 3-1 obtained in July 1989 are reported and analyzed. Strong Mg I and Mg II absorption is detected and attributed to two dust-containing envelopes (a ...transition zone and a neutral envelope) surrounding the central nebula. The observed He II 468.6- nm emission is found to come from the WR primary component of the binary nucleus, the secondary being most likely a B0 or B2 star. (D.G.)
Planetary nebula with a neutral envelope? GURZADYAN, G. A; EGIKYAN, A. G; TERZIAN, Y
Astrophysics and space science,
1991, 1991-00-00, 19910101, Letnik:
175, Številka:
2
Journal Article
Recenzirano
The IUE ultraviolet spectral recording for a low excitating planetary nebula NGC 6369 is obtained. The very strong doublet 2800 Mg II in emission as well as not less strong absorption line 2852 Mg I ...are discovered in the spectrum of this nebula. It is shown that the resonance line 2852 Mg I may originate only in a neutral envelope, around the nebula, consisting of neutral hydrogen, neutral magnesium, and dust particles (H I + Mg I). The possibility of the existence of one more envelope, transition zone immediately contacting with the bright that is ionized part of nebula (H II + Mg II), is also shown. The transition zone consists of neutral hydrogen, ionized magnesium and dust particles (H I + Mg II). The main parameters of this zone are also obtained. The temperature of the central star of this nebula is 48,000 K. Continuous background in the interval 2600- 3000 A is identified with Balmer continuum, with electron temperature T(c) = 12,500 K. (Author)
A principally new quantitative system of the classification of the spectra of planetary nebulae is proposed. Spectral class of excitation class of the nebula p is determined according to the relative ...intensities of forbidden mission lines (N1 + N2) O III /4686 He II and (N1 + N2) O III/H- beta. The excitation classes are obtained for 142 planetary nebulae of all classes - low (p = 1-3), middle (p = 4-8), and high (p = 9-12/+/). An empirical relationship between excitation class p, as an independent parameter, admit an evolutionary interpretation. It is shown that after reaching the highest class of excitation p = 12(+) the nebulae decrease their class of excitation with the further increases of sizes. (Author)
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