- PII
- 10.31857/S0016794023600060-1
- DOI
- 10.31857/S0016794023600060
- Publication type
- Status
- Published
- Authors
- Volume/ Edition
- Volume 63 / Issue number 4
- Pages
- 467-472
- Abstract
- Based on the medians of the F2-layer maximum electron concentration NmF2 for two ionospheric stations, Boulder and Hobart, in 1963–2013, an analysis of the dependence of the annual asymmetry local index R at noon on solar activity has been performed, where the R index is the January/July ratio of the summary NmF2 concentration for this pair of stations. Solar activity indices averaged over 81 days are used: Fobs is the solar radio emission flux at a wavelength of 10.7 cm measured by ground-based radio telescopes and Fadj is the value of Fobs reduced to a fixed distance from the Sun of one astronomical unit. It is found that the regression equations that manifest the NmF2 medians dependence on Fobs make it possible to obtain the annual asymmetry index R for a fixed value of Fobs with allowance for a substitution of Fobs by cFobs in these regression equations, the c coefficient is equal to 1.03 and 0.97 for January and July, respectively. The c = 1 case corresponds to neglecting the annual asymmetry in the Fobs index due to the ellipticity of the Earth’s orbit. For the c = 1 version, the R index increases with a solar activity increase from 1.2 under low activity up to almost 1.4 under high activity. An additional allowance for the annual asymmetry in Fobs leads to an increase in the R index by approximately 0.1 almost independently of the solar activity level. Apparently, this conclusion is being drawn for the first time. The Fadj index also makes it possible to obtain a correct estimate of the R index, because the annual asymmetry in the solar radiation flux is indirectly taken into account via the experimental values of NmF2.
- Keywords
- Date of publication
- 01.07.2023
- Year of publication
- 2023
- Number of purchasers
- 0
- Views
- 44
References
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