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Source of the Observed Enhancements in Thermospheric ΣO/N2 During Two Solar Eclipses in 2023
Zhang, Y.; Cantrall, C. E.; Mrak, S. +4 more
Two solar eclipse events in 2023 appeared to produce considerable enhancements in the thermospheric column density ratio of monatomic oxygen to molecular nitrogen (ΣO/N2) as measured by TIMED GUVI. We quantify potential sources for eclipse-induced ΣO/N2 changes and find that the observed enhancements arise from the ionospheri…
Jupiter's X-ray Emission During the 2007 Solar Minimum
Jackman, C. M.; Paranicas, C.; Ness, J. -U. +22 more
The 2007-2009 solar minimum was the longest of the space age. We present the first of two companion papers on Chandra and XMM-Newton X-ray campaigns of Jupiter through February-March 2007. We find that low solar X-ray flux during solar minimum causes Jupiter's equatorial regions to be exceptionally X-ray dim (0.21 GW at minimum; 0.76 GW at maximum…
Investigation of a Confined C-Class Flare in an Arch Filament System Close to a Regular Sunspot
Louis, Rohan Eugene
A moderate C1.1 class confined flare is investigated here, which occurred on 24 September 2013 at 22:56 UT, in an arch filament system close to a regular, unipolar sunspot. Spectropolarimetric observations from the Tenerife Infrared Polarimeter at the 70-cm German Vacuum Tower Telescope were combined with data from the Helioseismic Magnetic Imager…
Fine-pitch CdTe detector for hard X-ray imaging and spectroscopy of the Sun with the FOXSI rocket experiment
Takahashi, Tadayuki; Saito, Shinya; Watanabe, Shin +8 more
We have developed a fine-pitch hard X-ray (HXR) detector using a cadmium telluride (CdTe) semiconductor for imaging and spectroscopy for the second launch of the Focusing Optics Solar X-ray Imager (FOXSI). FOXSI is a rocket experiment to perform high sensitivity HXR observations from 4 to 15 keV using the new technique of HXR focusing optics. The …
Milne-Eddington inversion for unresolved magnetic structures in the quiet Sun photosphere
Bommier, Véronique
This paper is first devoted to present our method for modeling unresolved magnetic structures in the Milne-Eddington inversion of spectropolarimetric data. The related definitions and other approaches and different used inversion algorithms are recalled for comparison. In a second part, we apply our method to quiet Sun data outside active regions.…
Variations of the 3-D coronal magnetic field associated with the X3.4-class solar flare event of AR 10930
Chen, P. F.; Yan, Yihua; Wang, Huaning +2 more
The variations of the 3-D coronal magnetic fields associated with the X3.4-class flare of active region 10930 are studied in this paper. The coronal magnetic field data are reconstructed from the photospheric vector magnetograms obtained by the Hinode satellite and using the nonlinear force-free field extrapolation method developed in our previous…
Nonlinear force-free field extrapolation of the coronal magnetic field using the data obtained by the Hinode satellite
Yan, Yihua; Wang, Huaning; He, Han
The Hinode satellite can obtain high-quality photospheric vector magnetograms of solar active regions and the simultaneous coronal loop images in soft X-ray and extreme ultraviolet (EUV) bands. In this paper, we continue the work of He and Wang (2008) and apply the newly developed upward boundary integration computational scheme for the nonlinear …
Three-dimensional MHD modeling of the solar wind structures associated with 13 December 2006 coronal mass ejection
Kataoka, R.; Ebisuzaki, T.; Kusano, K. +4 more
A 3-D magnetohydrodynamic (MHD) simulation is performed to reconstruct the interplanetary propagation of a coronal mass ejection (CME) that occurred on 13 December 2006. A spheromak-type magnetic field is superposed on a realistic ambient solar wind to reproduce the large-scale interplanetary magnetic field (IMF) associated with the CME. Here we s…
Posteruptive phenomena in coronal mass ejections and substorms: Indicators of a universal process?
Webb, D. F.; Wiltberger, M.; Schwadron, N. A. +8 more
We examine phenomena associated with eruptions in the two different regimes of the solar corona and the terrestrial magnetosphere. We find striking similarities between the speeds of shrinking magnetic field lines in the corona and dipolarization fronts traversing the magnetosphere. We also examine the similarities between supra-arcade downflows o…