by Sterrewacht "Sonnenborgh," Laboratorium voor Ruimteonderzoek in Utrecht .
Written in English
|Statement||[by] A. D. Fokker.|
|Series||Utrechtse sterrekundige overdrukken, no. 16|
|LC Classifications||TL859 .U8 no. 16|
|The Physical Object|
|Number of Pages||366|
|LC Control Number||79559043|
We conducted an experiment in conjunction with the total solar eclipse of 1 August in China to determine the thermal electron temperature in the low solar corona close to the solar limb. The instrument, Imaging Spectrograph of Coronal Electrons (ISCORE), consisted of an 8 inch f/10 Schmidt Cassegrain telescope with a thermoelectrically Cited by: 2. flow; positions of maximum heating rate in solar corona. 1. Introduction For more than half a century, coronal white light (WL) brightness and polarization measurements from solar eclipses observations have been used to determine radial profiles of n e(r), the electron density in the solar corona. Values of H, the density scaleCited by: 8. The downward heat ﬂux is determined by the electron temperature gradient. Therefore, if there is a ﬁxed input of energy per particle into the base of a ﬂux tube and a ﬁxed energy per particle (or solar wind speed) out the top of the ﬂux tube, then the electron temperature gradient in the corona must balance the particle by: When combined with emission measure analysis, observations such as these can be used to understand the how much the composition varies from structure to structure in the solar corona. Work on the analysis of quiet Sun disk spectra are currently in progress and will be reported in a future paper Brooks et al. ().
corona (solar radius). However, coronal seismology in EUV lines fails for higher altitudes because of rapid decrease in line intensity. aim to use radio observations to estimate the plasma parameters of the outer solar corona (> R0). stationary state out of local equilibrium, the “apparent temperature” that would be deduced from the ratio of the number density of two successive ions being lower than the electron temperature. Therefore, the interpretation of the eclipse and UV observations of the lower solar corona has to be reconsidered owing to the non-LTE state of a. By using such an external data set, an independent validation of the previous results is possible. The models of the electron density derived by these two approaches agree well: the electron density at the Sun’s surface is calculated as (1. 24 ± 0. 42) × 10 12 m −3 (VLBI only) and (1. 31 ± 0. 51) × 10 12 m −3 (VLBI + GIM). The results. Satellite observations consistently provide evidence for the existence of power law tails on solar wind electron velocity distributions. Since solar wind electrons at 1 AU experience few Coulomb collisions en route to or from the solar corona, these observations suggest the existence of power law tails on coronal electron velocity distributions.
Even those early observations hinted at something very strange about the corona. The temperature in the corona is a blistering million or so degrees Celsius. But the temperature at the sun’s surface — the source of that energy — is a relatively balmy 5, degrees. “It’s just weird,” says Winebarger. The small-scale electron density irregularities in the ionosphere have a significant impact on the interruptions of Global Navigation Satellite System (GNSS) navigation and the accuracy of GNSS positioning techniques. The sporadic ionospheric E (Es) layer significantly contributes to the transient interruptions of signals (loss of lock) for GNSS tracking loops. These effects on the GNSS radio. Recent in situ observations of the solar wind show that charge states (e.g., the O7 +/O6 + and C6 +/C5 + abundance ratios) and α-particle composition evolved through the extended, deep solar minimum between solar cycles 23 and 24 (i.e., from to ). Prior investigations have found that both particle flux and magnetic field strength gradually decreased over this period of time. The K-coronal spectra derived from these spectra can be used to derive the coronal electron temperature and its flow speed. In the other instrument, ISCORE for Imaging Spectroscopy of Coronal Electrons, images of the corona were produced through four filters centered at four wavelength positions in the visible region each with a bandpass of