The elemental composition of the Sun III. The heavy elements Cu to Th

Grevesse, Nicolas; Scott, Pat; Asplund, Martin; Sauval, A. Jacques

doi:10.48550/arxiv.1405.0288

Cited by 8 publications

(10 citation statements)

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“…In Table 1 we collect the recommended solar photospheric abundances of various commonly observed elements from Grevesse and Sauval (1998), Asplund et al (2009), (also given in Grevesse et al, 2010) Caffau et al (2011), andScott et al (2014b,a) and Grevesse et al (2014) for comparison and reference. Not given here are result from Lodders (2010), who for the elements of most interest here appears to quote the average of Asplund et al (2009) and Caffau et al (2011).…”

Section: Reviewmentioning

confidence: 99%

The FIP and Inverse FIP Effects in Solar and Stellar Coronae

Laming

2015

Living Rev. Sol. Phys.

278

304

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We review our state of knowledge of coronal element abundance anomalies in the Sun and stars. We concentrate on the first ionization potential (FIP) effect observed in the solar corona and slow-speed wind, and in the coronae of solar-like dwarf stars, and the "inverse FIP" effect seen in the corona of stars of later spectral type; specifically M dwarfs. These effects relate to the enhancement or depletion, respectively, in coronal abundance with respect to photospheric values of elements with FIP below about 10~eV. They are interpreted in terms of the ponderomotive force due to the propagation and/or reflection of magnetohydrodynamic waves in the chromosphere. This acts on chromospheric ions, but not neutrals, and so can lead to ion-neutral fractionation. A detailed description of the model applied to closed magnetic loops, and to open field regions is given, accounting for the observed difference in solar FIP fractionation between the slow and fast wind. It is shown that such a model can also account for the observed depletion of helium in the solar wind. The helium depletion is sensitive to the chromospheric altitude where ion-neutral separation occurs, and the behavior of the helium abundance in the closed magnetic loop strongly suggests that the waves have a coronal origin. This, and other similar inferences may be expected to have a strong bearing on theories of solar coronal heating. Chromospheric waves originating from below as acoustic waves mode convert, mainly to fast mode waves, can also give rise to ion-neutral separation. Depending on the geometry of the magnetic field, this can result in FIP or Inverse FIP effects. We argue that such configurations are more likely to occur in later-type stars (known to have stronger field in any case), and that this explains the occurrence of the Inverse FIP effect in M dwarfs.Comment: Review paper submitted to Living Reviews in Solar Physics. 74 pages. Some material revised and updated from astro-ph/0405230, arXiv:0901.3350, arXiv:1110.435

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Section: Reviewmentioning

confidence: 99%

The FIP and Inverse FIP Effects in Solar and Stellar Coronae

Laming

2015

Living Rev. Sol. Phys.

278

304

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“…All results since the major revision of [12] by Asplund et al [13]. The most recent solar abundances of heavy elements from spectroscopic observations can be found in [14][15][16]. They do not change the general picture [17].…”

Section: Introduction a The Solar Abundance Problemmentioning

confidence: 81%

Axions as a probe of solar metals

Jaeckel

Thormaehlen

2019

Phys. Rev. D

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If axions or axion-like particles exist and are detected, they will not only extend the standard model of particle physics but will also open a new way to probe their sources. Axion helioscopes aim to detect axions which are produced in the core of the sun. Their spectrum contains information about the solar interior and could in principle help to solve the conflict between high and low metallicity solar models. Using the planned International Axion Observatory (IAXO) as an example, we show that helioscopes could measure the strength of characteristic emission peaks caused by the presence of heavier elements with good precision. In order to determine unambiguously the elemental abundances from this information, an improved modelling of the states of atoms inside the solar plasma is required. 4 Usually, the term axion-like particles refers particles similar to the QCD axion in that they are light (pseudo-)scalars and have very weak couplings to Standard Model particles, but they do not solve the strong CP problem. For our purposes only the two-photon and electron couplings are relevant. Their mass can be different from that of the QCD axion and can therefore be treated as a free parameter.

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“…Schmidt (1979); (3) Balona (1984); (4) Lester et al (1986); (5) Kane et al (1980); (6) Barnett & McKeith (1988); ( 7) Grigsby (1991); (8) Dufton et al (1981); (9) Peters & Polidan (1985) ; (10) Peters & Aller (1970); (11) Nieva & Przybilla (2012). Note: The first eleven columns represent abundances from difference sources and the last column represents the solar abundances which are taken from Scott et al (2014, I & II), Grevesse et al (2014) and (Asplund et al 2009) Table 2. This table shows the abundances determined in this work for every ion and the recommended value for every element, the solar abundances from Scott et al (2014, I & II), Grevesse et al (2014) and Asplund et al (2009), and the wavelengths used to determine these values.…”

Section: Acknowledgmentsmentioning

confidence: 99%

“…Note: The first eleven columns represent abundances from difference sources and the last column represents the solar abundances which are taken from Scott et al (2014, I & II), Grevesse et al (2014) and (Asplund et al 2009) Table 2. This table shows the abundances determined in this work for every ion and the recommended value for every element, the solar abundances from Scott et al (2014, I & II), Grevesse et al (2014) and Asplund et al (2009), and the wavelengths used to determine these values. Note that the recommended value is the variance of all the available literature values.…”

Section: Acknowledgmentsmentioning

confidence: 99%

Ultraviolet Spectral Synthesis of Iota Herculis

Golriz,

Landstreet

2016

Preprint

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In this Appendix, we present separately our detailed results for every element clearly identified in the spectrum of ι Her. The following sections are presented in ascending order of atomic number. The figures shows the observation in black (solid lines), the calculated model using the assigned abundance in blue (dash-dot-dot-dot lines) and calculated model in the absence of the specified element in red (long dash lines). In all figures, the vertical axis represents the normalized flux and the horizontal axis is the wavelength in Angstrom units, in vacuum. Boron, Z=5There are only a few boron lines in our VALD line list. According to the Saha equation (see Table 3), the dominant states of ionization in the atmosphere are B II and III. We have used the B II resonance line at 1362 .461 Å (Ryabtsev, 2005 for abundance determination. This is the only boron line expected to be detectable in our spectrum, and fortunately it is not heavily blended. The oscillator strength is very precisely known (it has quality "A" on the NIST Atomic Spectra Database scale, corresponding to an uncertainty of the transition probability of only about 3 % (Kramida et al., 2014), and since this is a resonance line of a dominant ionization state, our LTE treatment should introduce no important errors. We estimate the uncertainty from fitting to be about ±0.1. Therefore the abundance is log(nB/nH)= -10.1±0.1 for this element. Figure 1 shows the fit to the observed profile.Boron is a rare and fragile light element that is not produced through stellar nucleosynthesis (except for the very minor PP III chain), but is destroyed in the interiors of stars. There are several suggestion regarding the formation of this element, such as cosmic ray interactions with the ISM, or supernova neutrino spallation on particularly 4 He or 12 C (see Vangioni-Flam et al., 2000 for extensive details).In comparison with the solar abundance of log(nB/nH) = −9.30 ± 0.03 (Asplund et al., 2009), the abundance value found here is about a factor of 6 smaller. The presence of boron may indicate that outer layers of ι Her have at most been partially mixed into the stellar interior since the period of star formation. (In contrast, for instance, in Sirius A, the absence of detectable boron is consistent with the hypothesis that the outer layers were earlier inside its companion (Landstreet, 2011).) Carbon, Z=6Carbon is a very abundant element in the spectrum of ι Herculis. In the VALD line list used here, most of the carbon lines are in neutral form. The rest are lines of C II, C III, and C IV. The distribution of carbon over ionization states in LTE in the atmosphere of ι Her is shown in Table 3. Most carbon is in the form of C II and C III, and both contribute numerous lines. However, even though it is a very minor constituent, weaker C I lines are evident throughout the spectrum. No C IV lines are detected.We determined the abundance of carbon using a simultaneous fit to lines of C I UV multiplet (4) at 1329 Å, C II UV multiplet (11) at 1324 Å and UV muliplet (1) at 1335 Å...

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The elemental composition of the Sun III. The heavy elements Cu to Th

Cited by 8 publications

References 98 publications

The FIP and Inverse FIP Effects in Solar and Stellar Coronae

The FIP and Inverse FIP Effects in Solar and Stellar Coronae

Axions as a probe of solar metals

Ultraviolet Spectral Synthesis of Iota Herculis

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