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Related papers: Element Abundances: A New Diagnostic for the Solar…

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Connecting in-situ measured solar-wind plasma properties with typical regions on the Sun can provide an effective constraint and test to various solar wind models. We examine the statistical characteristics of the solar wind with an origin…

Solar and Stellar Astrophysics · Physics 2017-02-22 Hui Fu , Maria S. Madjarska , Lidong Xia , Bo Li , Zhenghua Huang , Zhipeng Wangguan

We study the abundances of the elements He through Pb in Fe-rich impulsive solar energetic-particle (SEP) events with measurable abundances of ions with atomic number Z>2 observed on the Wind spacecraft, and their relationship with coronal…

Solar and Stellar Astrophysics · Physics 2015-01-06 Donald V. Reames , Edward W. Cliver , Stephen W. Kahler

Although the origins of slow solar wind are unclear, there is increasing evidence that at least some of it is released in a steady state on over-expanded coronal hole magnetic field lines. This type of slow wind has similar properties to…

Space Physics · Physics 2020-01-28 D. Stansby , L. Matteini , T. S. Horbury , D. Perrone , R. D'Amicis , L. Berčič

Impulsive solar energetic-particle (SEP) events were first distinguished as the streaming electrons that produce type III radio bursts as distinct from shock-induced type II bursts. They were then observed as the surprisingly-enhanced…

Solar and Stellar Astrophysics · Physics 2023-10-30 Donald Reames

In the present work we utilize ACE/SWICS in-situ measurements of the properties of the solar wind outside ICMEs in order to determine whether, and to what extent are the solar wind properties affected by the solar cycle. We focus on proton…

Solar and Stellar Astrophysics · Physics 2022-01-17 A. Cardenas-O'Toole , E. Landi

We have spent 50 years in heated discussion over which populations of solar energetic particles (SEPs) are accelerated at flares and which by shock waves driven out from the Sun by coronal mass ejections (CMEs). The association of the large…

Solar and Stellar Astrophysics · Physics 2017-09-19 Donald V. Reames

In \citet{Stangalini20} and \citet{Deb20}, magnetic oscillations were detected in the chromosphere of a large sunspot and found to be linked to the coronal locations where a First Ionization Potential (FIP) effect was observed. In an…

Connecting the solar wind observed throughout the heliosphere to its origins in the solar corona is one of the central aims of heliophysics. The variability in the magnetic field, bulk plasma, and heavy ion composition properties of the…

Solar and Stellar Astrophysics · Physics 2023-05-26 B. J. Lynch , N. M. Viall , A. K. Higginson , L. Zhao , S. T. Lepri , X. Sun

We present and discuss the strong correspondence between evolution of the emission length scale in the lower transition region and in situ measurements of the fast solar wind composition during this most recent solar minimum. We combine…

Solar and Stellar Astrophysics · Physics 2015-05-30 Scott W. McIntosh , Kandace K. Kiefer , Robert J. Leamon , Justin C. Kasper , Michael S. Stevens

Recent observations with TRACE reveal that the time delay between the appearance of a cooling loop in different EUV temperature filters is proportional to the loop length, dt_12 ~ L. We model this cooling delay in terms of radiative loss…

Astrophysics · Physics 2009-11-16 Markus J. Aschwanden , C. J. Schrijver , A. R. Winebarger , H. P. Warren

A Chandra spectrum of the moderately active nearby F6 V star Pi3 Ori is used to study the coronal properties of mid-F dwarfs. We find that Pi3 Ori's coronal emission measure distribution is very similar to those of moderately active G and K…

Solar and Stellar Astrophysics · Physics 2015-06-15 Brian E. Wood , J. Martin Laming

We reexamine the relationship between energy spectral indices and element abundance enhancements in solar energetic particle (SEP) events at energies of a few MeV/amu. We find a correlated behavior only in the largest gradual SEP4 events…

Solar and Stellar Astrophysics · Physics 2022-03-09 Donald V. Reames

We study event-to-event variations in the abundance enhancements of the elements He through Pb for Fe-rich impulsive solar energetic-particle (SEP) events, and their relationship with properties of associated coronal mass ejections (CMEs)…

Solar and Stellar Astrophysics · Physics 2015-01-06 Donald V. Reames , Edward W. Cliver , Stephen W. Kahler

Element abundance ratios of magnesium to neon (Mg/Ne) and neon to oxygen (Ne/O) in the transition region of the quiet Sun have been derived by re-assessing previously published data from the Coronal Diagnostic Spectrometer on board the…

Solar and Stellar Astrophysics · Physics 2018-03-14 Peter R. Young

In solar energetic particle (SEP) events, the physical processes of both shock acceleration and scattering during transport can cause energy-spectral indices to be correlated with enhancement or suppression of element abundances versus…

Solar and Stellar Astrophysics · Physics 2021-01-29 Donald V. Reames

Elements with low First Ionization Potential (FIP) are known to be three to four times more abundant in active region loops of the solar corona than in the photosphere. There have been observations suggesting that this observed "FIP bias"…

One of the most interesting discoveries of the X-ray Telescope and EUV Imaging Spectrometer (EIS) on board the Hinode solar observatory is the presence of persistent high temperature high speed outflows from the edges of active regions.…

Solar and Stellar Astrophysics · Physics 2015-05-20 David H. Brooks , Harry P. Warren

We have reanalyzed SUMER observations of a parcel of coronal gas using new collisional ionization equilibrium (CIE) calculations. These improved CIE fractional abundances were calculated using state-of-the-art electron-ion recombination…

Astrophysics · Physics 2011-02-11 P. Bryans , E. Landi , D. W. Savin

Solar filaments/prominences are one of the most common features in the corona, which may lead to energetic coronal mass ejections (CMEs) and flares when they erupt. Filaments are about one hundred times cooler and denser than the coronal…

Solar and Stellar Astrophysics · Physics 2017-02-22 Hongqiang Song , Yao Chen , Bo Li , Leping Li , Liang Zhao , Jiansen He , Die Duan , Xin Cheng , Jie Zhang

Abundance enhancements, during acceleration and transport in both gradual and impulsive solar energetic particle (SEP) events, vary approximately as power laws in the mass-to-charge ratio [A/Q] of the ions. Since the Q-values depend upon…

Solar and Stellar Astrophysics · Physics 2016-07-22 Donald V. Reames
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