Line formation in solar granulation VI. [C I], C I, CH and C2 lines and the photospheric C abundance

The solar photospheric carbon abundance has been determined from [C I], C I, CH vibration-rotation, CH A-X electronic and C2 Swan electronic lines by means of a time-dependent, 3D, hydrodynamical model of the solar atmosphere. Departures from LTE have been considered for the C I lines. These turned out to be of increasing importance for stronger lines and are crucial to remove a trend in LTE abundances with the strengths of the lines. Very gratifying agreement is found among all the atomic and molecular abundance diagnostics in spite of their widely different line formation sensitivities. The mean of the solar carbon abundance based on the four primary abundance indicators ([C I], C I, CH vibration-rotation, C_2 Swan) is log C = 8.39 +/- 0.05, including our best estimate of possible systematic errors. Consistent results also come from the CH electronic lines, which we have relegated to a supporting role due to their sensitivity to the line broadening. The new 3D based solar C abundance is significantly lower than previously estimated in studies using 1D model atmospheres.Comment: Accepted for A&A, 13 page

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

We re-evaluate the abundances of the elements in the Sun from copper (Z = 29) to thorium (Z = 90). Our results are mostly based on neutral and singly-ionised lines in the solar spectrum. We use the latest 3D hydrodynamic solar model atmosphere, and in a few cases also correct for departures from local thermodynamic equilibrium (LTE) using non-LTE (NLTE) calculations performed in 1D. In order to minimise statistical and systematic uncertainties, we make stringent line selections, employ the highest-quality observational data and carefully assess oscillator strengths, hyperfine constants and isotopic separations available in the literature, for every line included in our analysis. Our results are typically in good agreement with the abundances in the most pristine meteorites, but there are some interesting exceptions. This analysis constitutes both a full exposition and a slight update of the relevant parts of the preliminary results we presented in Asplund et al. (2009, ARA&A, 47, 481), including full line lists and details of all input data that we have employed

Apprentissage de la lecture et phonologie : implication du code phonologique dans la reconnaissance de mots écrits chez l'enfant

We conducted five studies to examine the role of phonological code in visual word recognition in children more or less advanced in learning to read. For that, we used the priming paradigm (in visual, auditory and inter modalities). This paradigm allows to study on-line and in precise manner, phonological and orthographic processes engaged in visual word recognition. The studies 1 and 2 indicate that, in Grade 3 and Grade 5, speech representations are involved in silent reading of pseudowords, in phonetic feature format and in visual familiar word recognition, in phonemic format. The study 3 indicates that phonological code contributes to visual word recognition in stable manner through Grade 3 and Grade 5. Nevertheless, when lexical orthographic representations are not well specified, phonological contribution is greater. The studies 4 and 5, in phonological (O-P+ vs O-P-) and ortho-phonological (O+P+ vs O+P-) visual masked priming, show that familiar visual word recognition involves phonological representations in automatic manner from Grade 3 to Grade 5. In contrast, automatic activation of orthographic representations seems to develop later (Grade 5). These results suggest that when orthographic process is functional but not fully effective (Grade 3), visual word recognition benefits from phonological activation whereas when orthographic process is fully effective (Grade 5), visual word recognition benefits from orthographic activation. That suggests that development of phonological automatic activation and development of orthographic automatic activation are independent. The process of phonological automatic activation is entirely developed earlier than the process of orthographic automatic activation.Nous avons examiné à travers cinq études le rôle de la phonologie dans la reconnaissance de mots écrits chez des enfants tout-venant plus ou moins avancés dans l’apprentissage de la lecture. Pour cela, nous avons utilisé le paradigme de l’amorçage dans des versions visuelles, auditives et intermodales. Ce paradigme, à ce jour peu utilisé dans les études chez l’enfant, permet d’étudier, en temps réel et de manière précise, les processus phonologique et orthographiques engagés dans la reconnaissance de mots. Les études 1 et 2 montrent que chez les jeunes lecteurs, les représentations phonologiques du langage oral sont impliquées dans la lecture silencieuse de pseudomots, dans un format trait phonétique et dans la reconnaissance de mots familiers écrits, dans un format phonémique. L’étude 3 indique que le code phonologique contribue à la reconnaissance des mots de manière stable entre le CE2 et le CM2. Néanmoins, lorsque les représentations orthographiques sont peu spécifiées, la contribution du code phonologique est plus importante. Les études 4 et 5, en amorçage masqué visuel phonologique (O-P+ vs O-P-) et ortho-phonologique (O+P+ vs O+P-), montrent qu’au cours de la reconnaissance de mots familiers, les représentations phonologiques sont activées de manière automatique et ce dès le CE2. En revanche, l’activation automatique des représentations orthographiques semble apparaître plus tardivement dans le développement (CM2). Nos résultats suggèrent que lorsque le processus orthographique est fonctionnel mais pas encore pleinement efficace (CE2), la reconnaissance des mots écrits bénéficie de l’activation phonologique alors que, lorsque le processus est pleinement efficace (CM2), la reconnaissance des mots bénéficie de l’activation orthographique. Il semble donc que le développement du processus d’activation automatique des représentations phonologiques et le développement du processus d’activation automatique du lexique orthographique soient indépendants, le premier se développerait pleinement avant le second

The elemental composition of the Sun II. The iron group elements Sc to Ni

We redetermine the abundances of all iron group nuclei in the Sun, based on neutral and singly-ionised lines of Sc, Ti, V, Mn, Fe, Co and Ni in the solar spectrum. We employ a realistic 3D hydrodynamic model solar atmosphere, corrections for departures from local thermodynamic equilibrium (NLTE), stringent line selection procedures and high quality observational data. We have scoured the literature for the best quality oscillator strengths, hyperfine constants and isotopic separations available for our chosen lines. We find log ϵSc = 3.16 ± 0.04, log ϵTi = 4.93 ± 0.04, log ϵV = 3.89 ± 0.08, log ϵCr = 5.62 ± 0.04, log ϵMn = 5.42 ± 0.04, log ϵFe = 7.47 ± 0.04, log ϵCo = 4.93 ± 0.05 and log ϵNi = 6.20 ± 0.04. Our uncertainties factor in both statistical and systematic errors (the latter estimated for possible errors in the model atmospheres and NLTE line formation). The new abundances are generally in good agreement with the CI meteoritic abundances but with some notable exceptions. This analysis constitutes both a full exposition and a slight update of the preliminary results we presented in Asplund et al. (2009, ARA&A, 47, 481), including full line lists and details of all input data we employed

On the solar nickel and oxygen abundances

Determinations of the solar oxygen content relying on the neutral forbidden transition at 630 nm depend upon the nickel abundance, due to a Ni I blend. Here we rederive the solar nickel abundance, using the same ab initio 3D hydrodynamic model of the solar photosphere employed in the recent revision of the abundances of C, N, O and other elements. Using 17 weak, unblended lines of Ni I together with the most accurate atomic and observational data available we find log epsilon_Ni = 6.17 +/- 0.02 (statistical) +/- 0.05 (systematic), a downwards shift of 0.06 to 0.08 dex relative to previous 1D-based abundances. We investigate the implications of the new nickel abundance for studies of the solar oxygen abundance based on the [O I] 630 nm line in the quiet Sun. Furthermore, we demonstrate that the oxygen abundance implied by the recent sunspot spectropolarimetric study of Centeno & Socas-Navarro needs to be revised downwards from log epsilon_O = 8.86 +/- 0.07 to 8.71 +/- 0.10. This revision is based on the new nickel abundance, application of the best available gf-value for the 630 nm forbidden oxygen line, and a more transparent treatment of CO formation. Determinations of the solar oxygen content relying on forbidden lines now appear to converge around log epsilon_O = 8.7.Comment: v2 matches published versio

Automated spectroscopic abundances of A and F-type stars using echelle spectrographs I. Reduction of ELODIE spectra and method of abundance determination

This paper presents an automated method to determine detailed abundances for A and F-type stars. This method is applied on spectra taken with the ELODIE spectrograph. Since the standard reduction procedure of ELODIE is optimized to obtain accurate radial velocities but not abundances, we present a more appropriate reduction procedure based on IRAF. We describe an improvement of the method of Hill & Landstreet (1993) for obtaining Vsini, microturbulence and abundances by fitting a synthetic spectrum to the observed one. In particular, the method of minimization is presented and tested with Vega and the Sun. We show that it is possible, in the case of the Sun, to recover the abundances of 27 elements well within 0.1 dex of the commonly accepted values.Comment: 12 pages, 10 figures, accepted for publication in A&

3D simulations of M star atmosphere velocities and their influence on molecular FeH lines

We present an investigation of the velocity fields in early to late M-type star hydrodynamic models, and we simulate their influence on FeH molecular line shapes. The M star model parameters range between log g of 3.0 - 5.0 and Teff of 2500 K and 4000 K. Our aim is to characterize the Teff- and log g -dependence of the velocity fields and express them in terms of micro- and macro-turbulent velocities in the one dimensional sense. We present also a direct comparison between 3D hydrodynamical velocity fields and 1D turbulent velocities. The velocity fields strongly affect the line shapes of FeH, and it is our goal to give a rough estimate for the log g and Teff parameter range in which 3D spectral synthesis is necessary and where 1D synthesis suffices. In order to calculate M-star structure models we employ the 3D radiative-hydrodynamics (RHD) code CO5BOLD. The spectral synthesis on these models is performed with the line synthesis code LINFOR3D. We describe the 3D velocity fields in terms of a Gaussian standard deviation and project them onto the line of sight to include geometrical and limb-darkening effects. The micro- and macro-turbulent velocities are determined with the "Curve of Growth" method and convolution with a Gaussian velocity profile, respectively. To characterize the log g and Teff dependence of FeH lines, the equivalent width, line width, and line depth are regarded. The velocity fields in M-stars strongly depend on log g and Teff. They become stronger with decreasing log g and increasing Teff.Comment: 14 pages, 17 figures, 3 tables, accepted by Astronomy & Astrophysic

Ten Years Evidence-based High-Tech Acupuncture—A Short Review of Peripherally Measured Effects*

Since 1997, the Research Unit of Biomedical Engineering in Anesthesia and Intensive Care Medicine of Graz Medical University has been dealing with the demystification of acupuncture and examining, using non-invasive methods, how different stimulation modalities (manual needle acupuncture, laserneedle acupuncture and electro acupuncture) affect peripheral and central functions. Laser is also an important instrument for acupuncture. One only needs to mention the treatment of children or of patients with needle phobia. The laserneedle acupuncture, which was examined scientifically for the first time in Graz, represents a new painless acupuncture method for which up to ten laserneedles are glued to the skin, but not stuck into it. This first part of the short review article summarizes some of the peripherally measured effects of acupuncture obtained at the Medical University of Graz within the last 10 years

Deuterated hydrogen chemistry: Partition functions, Equilibrium constants and Transition intensities for the H3+ system

H3+ and the deuterated isotopomers are thought to play an important role in interstellar chemistry. The partition functions of H3+, D2H+ and D3+ are calculated to a temperature of 800 K by explicitly summing the ab initio determined rotation-vibration energy levels of the respective species. These partition functions are used to calculate the equilibrium constants for nine important reactions in the interstellar medium involving H3+ and its deuterated isotopomers. These equilibrium constants are compared to previously determined experimental and theoretical values. The Einstein A coefficients for the strongest dipole transitions are also calculated