New atmospheric parameters and spectral interpolator for the MILES cool stars

Sharma, Kaushal; Prugniel, Philippe; Singh, Harinder P.

doi:10.1051/0004-6361/201526111

Cited by 53 publications

(87 citation statements)

References 112 publications

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“…Since we see in Figure 18 that for most of the library (∼ 90%) the rms difference between the observed and interpolated spectra is < 5% we can feel confident that the stellar parameters from Prugniel et al (2011) and Sharma et al (2016) are internally self-consistent. We looked at Figure 18 separately for the MILES and IRTF spectra and found that the recovery is about the same for the majority of the stars.…”

Section: Quality Of Interpolationmentioning

confidence: 79%

“…Throughout this work we use the stellar parameters determined by Prugniel et al (2011) and Sharma et al (2016) instead of those reported by Cenarro et al (2007). The stellar parameters determined by Cenarro et al (2007) were determined heterogeneously, depending on which additional literature data was available for a given star.…”

Section: Sample Selectionmentioning

confidence: 99%

“…They used ELODIE spectra to perform full-spectrum χ 2 minimization fits (Koleva et al 2009) between the MILES spectra and templates built from the ELODIE 3.2 library (Wu et al 2011). Sharma et al (2016) revised the stellar parameter values of MILES library stars with T eff < 4800 K with an improved interpolator.…”

Section: Sample Selectionmentioning

confidence: 99%

“…Prospector is a code for inference of physical parameters from spectroscopic data via MCMC sampling of the posterior probability distributions. To obtain estimates of the posterior velocity distribution using prospector, a spectral model is constructed for each star by linearly interpolating the C3K theoretical spec- tral models 7 to the Prugniel et al (2011) and Sharma et al (2016) parameters, and then broadened to the resolution of IRTF. At each MCMC step this spectrum is shifted in velocity and the likelihood of the data given the redshifted model is calculated, after masking regions of strong telluric lines.…”

Section: Data Reductionmentioning

confidence: 99%

“…Global interpolation is appropriate when the surface is smooth and can be approximated by a (relatively) simple function. The interpolators of Vazdekis et al (2003) and Dries et al (2016) are local interpolators while the interpolators described in Prugniel et al (2011), Ness et al (2015, and Sharma et al (2016) are global.…”

Section: Spectral Polynomial Interpolatormentioning

confidence: 99%

See 4 more Smart Citations

The Extended IRTF Spectral Library: Expanded Coverage in Metallicity, Temperature, and Surface Gravity

Villaume

Conroy

Johnson

et al. 2017

ApJS

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We present a 0.7 − 2.5µm spectral library of 284 stars observed with the medium-resolution infrared spectrograph, SpeX, at the 3.0 meter NASA Infrared Telescope Facility (IRTF) on Maunakea, Hawaii. This library extends the metallicity range of the IRTF Cool Star library beyond solar metallicity to −1.7 < [Fe/H] < 0.6. All of the observed stars are also in the MILES optical stellar library, providing continuous spectral coverage for each star from 0.35 − 2.5µm. The spectra are absolute flux calibrated using Two Micron All Sky Survey photometry and the continuum shape of the spectra is preserved during the data reduction process. Synthesized JHK S colors agree with observed colors at the 1 − 2% level, on average. We also present a spectral interpolator that uses the library to create a datadriven model of spectra as a function of T eff , log g, and [Fe/H]. We use the library and interpolator to compare empirical trends with theoretical predictions of spectral feature behavior as a function of stellar parameters. These comparisons extend to the previously difficult to access low-metallicity and cool dwarf regimes, as well as the previously poorly sampled super-solar metallicity regime. The library and interpolator are publicly available.

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Section: Quality Of Interpolationmentioning

confidence: 79%

Section: Sample Selectionmentioning

confidence: 99%

Section: Sample Selectionmentioning

confidence: 99%

Section: Data Reductionmentioning

confidence: 99%

Section: Spectral Polynomial Interpolatormentioning

confidence: 99%

See 3 more Smart Citations

The Extended IRTF Spectral Library: Expanded Coverage in Metallicity, Temperature, and Surface Gravity

Villaume

Conroy

Johnson

et al. 2017

ApJS

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Spectroscopic and photometric confirmation of chromospheric activity in four stars

Özdarcan

Dal

2018

Astron Nachr

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We present analysis of medium resolution optical spectra and long term V band photometry of four cool stars, BD+13 5000, BD+11 3024, TYC 3557-919-1 and TYC 5163-1764-1. Our spectroscopic analysis reveals that the stars are giant or sub-giant from K0 or K1 spectral type, and all of them exhibit emission features in their Ca ii H& K lines. These features appear to be modulated with the rotation of the stars. Except BD+11 3024, we observe that the radial velocities of the target stars are not stable, which suggests that each of them might be a member of a binary system. Global analysis of photometric data indicates clear cyclic variation for BD+13 5000 and TYC 5163-1764-1 with a period of 8.0±0.3 and 5.04±0.04 year, respectively. Besides that, we observe a dramatic increase (∼0. m 7) in the mean brightness of BD+11 3024, accompanied with a 2.87 ± 0.12 cyclic variation, embedded into the global brightening trend, which indicates possible multiple cycles on this star.

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Stellar atmospheric parameters for 754 spectra from the X-shooter Spectral Library

Arentsen

Prugniel

Gonneau

et al. 2019

A&A

Self Cite

121

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Context. The X-shooter Spectral Library (XSL) is an empirical stellar library at medium spectral resolution covering the wavelength range from 3000 Å to 24 800 Å. This library aims to provide a benchmark for stellar population studies. Aims. In this work, we present a uniform set of stellar atmospheric parameters, effective temperatures, surface gravities, and iron abundances for 754 spectra of 616 XSL stars. Methods. We used the full-spectrum fitting package ULySS with the empirical MILES library as reference to fit the ultraviolet-blue (UVB) and visible (VIS) spectra. We tested the internal consistency and we compared our results with compilations from the literature. Results. The stars cover a range of effective temperature 2900 < T eff < 38 000 K, surface gravity 0 < log g < 5.7, and iron abundance −2.5 < [Fe/H] < +1.0, with a couple of stars extending down to [Fe/H] = −3.9. The precisions of the measurements for the G-and K-type stars are 0.9%, 0.14, and 0.06 in T eff , log g, and [Fe/H], respectively. For the cool giants with log g < 1, the precisions are 2.1%, 0.21, and 0.22, and for the other cool stars these values are 1%, 0.14, and 0.10. For the hotter stars (T eff > 6500 K), these values are 2.6%, 0.20, and 0.10 for the three parameters.

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New atmospheric parameters and spectral interpolator for the MILES cool stars

Cited by 53 publications

References 112 publications

The Extended IRTF Spectral Library: Expanded Coverage in Metallicity, Temperature, and Surface Gravity

The Extended IRTF Spectral Library: Expanded Coverage in Metallicity, Temperature, and Surface Gravity

Spectroscopic and photometric confirmation of chromospheric activity in four stars

Stellar atmospheric parameters for 754 spectra from the X-shooter Spectral Library

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