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Thuillier, G.; Hersé, M.; Simon, P. C.; Labs, D.; Mandel, H.; Gillotay, D.; Foujols, Thomas

doi:10.1023/a:1004953215589

Cited by 107 publications

(96 citation statements)

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“…The spectra were averaged every 10 Å between 3305 and 6295 Å, and every 20 Å between 6310 and 8690 Å. Thuillier et al (2003) presented the solar irradiance from 2000 Å to 24 000 Å obtained with the SOLSPEC and SOSP spectrometers mounted on space missions. However, for wavelength ranges above 8700 Å, their data are sampled with a rate different from that in visible and UV domains.…”

Section: Spectral Energy Distributionsmentioning

confidence: 99%

“…Therefore we only adopted the spectra below 8700 Å to compare with our solar fluxes. Figure 4 shows the data and absolute deviations of solar irradiance of Neckel & Labs (1984) and Thuillier et al (2003) together with the computed solar fluxes for three different α CMA values of 0.5, 1.5, and 2.5. A visual check prefers a fit between blue (α CMA = 2.5) and green (α CMA = 1.5).…”

Section: Spectral Energy Distributionsmentioning

confidence: 99%

“…Nevertheless, data points with values below 1.0 can be excluded from the Neckel data. The data of Thuillier et al (2003) would only allow for very low convective efficiency if the blue region is ignored. In general, we find an overestimation of the solar flux in the regime below 5000 Å.…”

Section: Near-uv -Visible -Near-ir Domainmentioning

confidence: 99%

“…All the remaining dwarf and subgiant stars were assumed to be slow rotators, with V sin i ≤ 1 km s −1 . It is worth noting that the thermal broadening of Balmer lines, with the most probable velocity of about V t = 10 km s −1 in the atmospheres of the investigated stars, is more pronounced than the broadening caused by rotation, A134, page 5 of 13 Neckel & Labs (1984) and Thuillier et al (2003). Observational data between 4500 and 8700 Å (left plots) and between 5500 and 8700 Å (right plots) were taken into account.…”

Section: Nlte Calculations Of Balmer-line Profilesmentioning

confidence: 99%

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Calibrating theαparameter of convective efficiency using observed stellar properties

Alexeeva

Mashonkina

et al. 2015

A&A

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Context. Synthetic model atmosphere calculations are still the most commonly used tool when determining precise stellar parameters and stellar chemical compositions. Besides three-dimensional models that consistently solve for hydrodynamic processes, onedimensional models that use an approximation for convective energy transport play the major role. Aims. We use modern Balmer-line formation theory as well as spectral energy distribution (SED) measurements for the Sun and Procyon to calibrate the model parameter α that describes the efficiency of convection in our 1D models. Convection was calibrated over a significant range in parameter space, reaching from F-K along the main sequence and sampling the turnoff and giant branch over a wide range of metallicities. This calibration was compared to theoretical evaluations and allowed an accurate modeling of stellar atmospheres. Methods. We used Balmer-line fitting and SED fits to determine the convective efficiency parameter α. Both methods are sensitive to the structure and temperature stratification of the deeper photosphere. Results. While SED fits do not allow a precise determination of the convective parameter for the Sun and Procyon, they both favor values significantly higher than 1.0. Balmer-line fitting, which we find to be more sensitive, suggests that the convective efficiency parameter α is ≈2.0 for the main sequence and quickly decreases to ≈1.0 for evolved stars. These results are highly consistent with predictions from 3D models. While the values on the main sequence fit predictions very well, measurements suggest that the decrease of convective efficiency as stars evolve to the giant branch is more dramatic than predicted by models.

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Section: Spectral Energy Distributionsmentioning

confidence: 99%

Section: Spectral Energy Distributionsmentioning

confidence: 99%

Section: Near-uv -Visible -Near-ir Domainmentioning

confidence: 99%

Section: Nlte Calculations Of Balmer-line Profilesmentioning

confidence: 99%

See 2 more Smart Citations

Calibrating theαparameter of convective efficiency using observed stellar properties

Alexeeva

Mashonkina

et al. 2015

A&A

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“…The SOLSPEC instrument was flown on several space missions in the 1980s and 1990s (Thuillier et al 1981(Thuillier et al , 1997(Thuillier et al , 2003 and provided the well-known composite ATLAS 1 and 3 spectra (Thuillier et al 2004), where ATLAS is an acronym for ATmospheric Laboratory for Applications and Science on board the Space Shuttle). From (Ly-α) to 200 nm, the data from SUSIM and SOLSTICE on UARS were used for these reference spectra.…”

Section: Introductionmentioning

confidence: 99%

SOLAR/SOLSPEC mission on ISS: In-flight performance for SSI measurements in the UV

Bolsée

Pereira

Gillotay

et al. 2017

A&A

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Context. The SOLar SPECtrum (SOLSPEC) experiment is part of the Solar Monitoring Observatory (SOLAR) payload, and has been externally mounted on the Columbus module of the International Space Station (ISS) since 2008. SOLAR/SOLSPEC combines three absolutely calibrated double monochromators with concave gratings for measuring the solar spectral irradiance (SSI) from 166 nm to 3088 nm. This physical quantity is a key input for studies of climatology, planetary atmospheres, and solar physics. Aims. A general description of the instrument is given, including in-flight operations and performance of the ultraviolet (UV) channel from 175 nm to 340 nm. Methods. We developed a range of processing and correction methods, which are described in detail. For example, methods for correcting thermal behavior effects, instrument linearity, and especially the accuracy of the wavelength and absolute radiometric scales have been validated by modeling the standard uncertainties. Results. The deliverable is a quiet Sun UV reference solar spectrum as measured by SOLAR/SOLSPEC during the minimum of solar activity prior to cycle 24. Comparisons with other instruments measuring SSI are also presented.

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UV solar irradiance in observations and the NRLSSI and SATIRE‐S models

et al. 2015

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Total solar irradiance and UV spectral solar irradiance has been monitored since 1978 through a succession of space missions. This is accompanied by the development of models aimed at replicating solar irradiance by relating the variability to solar magnetic activity. The Naval Research Laboratory Solar Spectral Irradiance (NRLSSI) and Spectral And Total Irradiance REconstruction for the Satellite era (SATIRE‐S) models provide the most comprehensive reconstructions of total and spectral solar irradiance over the period of satellite observation currently available. There is persistent controversy between the various measurements and models in terms of the wavelength dependence of the variation over the solar cycle, with repercussions on our understanding of the influence of UV solar irradiance variability on the stratosphere. We review the measurement and modeling of UV solar irradiance variability over the period of satellite observation. The SATIRE‐S reconstruction is consistent with spectral solar irradiance observations where they are reliable. It is also supported by an independent, empirical reconstruction of UV spectral solar irradiance based on Upper Atmosphere Research Satellite/Solar Ultraviolet Spectral Irradiance Monitor measurements from an earlier study. The weaker solar cycle variability produced by NRLSSI between 300 and 400 nm is not evident in any available record. We show that although the method employed to construct NRLSSI is principally sound, reconstructed solar cycle variability is detrimentally affected by the uncertainty in the SSI observations it draws upon in the derivation. Based on our findings, we recommend, when choosing between the two models, the use of SATIRE‐S for climate studies.

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Cited by 107 publications

References 0 publications

Calibrating theαparameter of convective efficiency using observed stellar properties

Calibrating theαparameter of convective efficiency using observed stellar properties

SOLAR/SOLSPEC mission on ISS: In-flight performance for SSI measurements in the UV

UV solar irradiance in observations and the NRLSSI and SATIRE‐S models

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