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Journal articles on the topic 'Stellar parameters'

Author: Grafiati

Published: 4 June 2021

Last updated: 1 February 2022

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1

Bruntt, Hans. "Accurate Fundamental Stellar Parameters." Proceedings of the International Astronomical Union 5, S265 (August 2009): 215–16. http://dx.doi.org/10.1017/s1743921310000591.

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AbstractWe combine results from interferometry, asteroseismology and spectroscopic analyses to determine accurate fundamental parameters (mass, radius and effective temperature) of 10 bright solar-type stars covering the H-R diagram from spectral type F5 to K1. Using “direct” techniques that are only weakly model-dependent we determine the mass, radius and effective temperature. We demonstrate that model-dependent or “indirect” methods can be reliably used even for relatively faint single stars for which direct methods are not applicable. This is important for the characterization of the targets of the CoRoT and Kepler space missions.

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Grootel, Valérie Van, Catarina S. Fernandes, Michael Gillon, Emmanuel Jehin, Jean Manfroid, Richard Scuflaire, Adam J. Burgasser, et al. "Stellar Parameters for Trappist-1." Astrophysical Journal 853, no. 1 (January 19, 2018): 30. http://dx.doi.org/10.3847/1538-4357/aaa023.

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Decin, L., Z. Shkedy, G. Molenberghs, M. Aerts, and C. Aerts. "Estimating stellar parameters from spectra." Astronomy & Astrophysics 421, no. 1 (June 11, 2004): 281–94. http://dx.doi.org/10.1051/0004-6361:20040127.

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Ge, Junqiang, Shude Mao, Youjun Lu, Michele Cappellari, and Renbin Yan. "Recovering stellar population parameters via different population models and stellar libraries." Monthly Notices of the Royal Astronomical Society 485, no. 2 (February 11, 2019): 1675–93. http://dx.doi.org/10.1093/mnras/stz418.

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Martins, F., M. Bergemann, J. M. Bestenlehner, P. A. Crowther, W. R. Hamann, F. Najarro, M. F. Nieva, et al. "SpS5 - II. Stellar and wind parameters." Proceedings of the International Astronomical Union 10, H16 (August 2012): 420–28. http://dx.doi.org/10.1017/s1743921314011788.

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AbstractThe development of infrared observational facilities has revealed a number of massive stars in obscured environments throughout the Milky Way and beyond. The determination of their stellar and wind properties from infrared diagnostics is thus required to take full advantage of the wealth of observations available in the near and mid infrared. However, the task is challenging. This session addressed some of the problems encountered and showed the limitations and successes of infrared studies of massive stars.

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GAO, HUA, HUA-WEI ZHANG, MAO-SHENG XIANG, YANG HUANG, XIAO-WEI LIU, A.-LI LUO, HAO-TONG ZHANG, et al. "ACCURACY OF LAMOST DR1 STELLAR PARAMETERS." Publications of The Korean Astronomical Society 30, no. 2 (September 30, 2015): 279–81. http://dx.doi.org/10.5303/pkas.2015.30.2.279.

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7

Ryabchikova, T. A., L. I. Mashonkina, A. R. Titarenko, S. A. Alexeeva, Yu V. Pakhomov, N. E. Piskunov, T. M. Sitnova, and B. A. Nizamov. "Testing SME determination of stellar parameters." Proceedings of the International Astronomical Union 9, S298 (May 2013): 436. http://dx.doi.org/10.1017/s1743921313007023.

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8

Miglio, A., and J. Montalbán. "Constraining fundamental stellar parameters using seismology." Astronomy & Astrophysics 441, no. 2 (September 19, 2005): 615–29. http://dx.doi.org/10.1051/0004-6361:20052988.

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Jordi, C., C. Fabricius, J. M. Carrasco, F. Figueras, E. Masana, H. Voss, and X. Luri. "Stellar parameters through high precision parallaxes." Proceedings of the International Astronomical Union 3, S248 (October 2007): 500–501. http://dx.doi.org/10.1017/s1743921308019947.

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AbstractBefore Hipparcos, the determination of absolute luminosity was usually done through calibrations based on a few stellar parallaxes measured at the highest precision. The Hipparcos mission meant a giant step on the knowledge of luminosities and fine structure of the HR diagram. The Gaia mission will go an enormous step further. Besides luminosities, Gaia will allow us to derive other stellar parameters like temperature and extinction, gravity, chemical composition, age and mass by the combination of astrometric and spectrometric data. Through simulations during the mission preparation, it has been shown that the astrometric parallax information is essential to deal with the degeneracy between gravity and chemical composition ([Fe/H] and [α/Fe]), that cannot be treated using only spectrophotometry. We show the expected HR diagram for the Gaia domain and the accuracies of stellar parameters.

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10

Gould, Andrew. "Stellar Halo Parameters from 4588 Subdwarfs." Astrophysical Journal 583, no. 2 (February 2003): 765–75. http://dx.doi.org/10.1086/345446.

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Monguió, M., F. Figueras, and P. Grosbøl. "Stellar physical parameters from Strömgren photometry." Astronomy & Astrophysics 568 (August 2014): A119. http://dx.doi.org/10.1051/0004-6361/201423703.

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Ludwig, H. G. "Perspectives for Determining Stellar Surface Parameters." EAS Publications Series 45 (2010): 251–56. http://dx.doi.org/10.1051/eas/1045042.

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Bruntt, H., M. Deleuil, M. Fridlund, R. Alonso, F. Bouchy, A. Hatzes, M. Mayor, C. Moutou, and D. Queloz. "Improved stellar parameters of CoRoT-7." Astronomy and Astrophysics 519 (September 2010): A51. http://dx.doi.org/10.1051/0004-6361/201014143.

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Soubiran, C., J. F. Le Campion, G. Cayrel de Strobel, and A. Caillo. "The PASTEL catalogue of stellar parameters." Astronomy and Astrophysics 515 (June 2010): A111. http://dx.doi.org/10.1051/0004-6361/201014247.

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15

Posbic, H., D. Katz, E. Caffau, P. Bonifacio, A. Gómez, L. Sbordone, and F. Arenou. "SPADES: a stellar parameters determination software." Astronomy & Astrophysics 544 (August 2012): A154. http://dx.doi.org/10.1051/0004-6361/201219417.

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Rigliaco, E., A. Natta, L. Testi, S. Randich, E. Covino, and J. M. Alcalá. "Stellar parameters of young brown dwarfs." Astronomische Nachrichten 332, no. 3 (March 2011): 249–50. http://dx.doi.org/10.1002/asna.201111527.

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17

Wenske, V., and D. Schönberner. "Influence of Rotation on the Stellar Parameters." International Astronomical Union Colloquium 137 (1993): 162–64. http://dx.doi.org/10.1017/s0252921100017668.

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For several years it has become quite common to derive stellar parameters like effective temperature, Teff, and surface acceleration, g, by means of properly calibrated photometric indices, and to use these values for the derivation of important properties of stellar aggregates (viz. ages, star formation history, distances, etc.). Photometric observations, however, fail to give informations about one important property of a star: its rotational rate!The main effect of rotation is to increase the size of the star, mainly in the equatorial region, leading to lower surface temperatures and accelerations. Since in non–spherical stars Teff and g depend on the latitude, the observed values, which are, of course, averages over the visible hemisphere, depend on the angle of inclination, i. Collins & Sonneborn (1977) utilized the rigidly rotating stellar models of Sackmann and Anand (1970) to compute emergent fluxes and photometric indices for various stellar masses, inclination angles i and rotational parameters being the break–up rotational rate. These indices, viz. C0 and β, represent then averages over the visible part of the rotally distorted stellar models. Closer inspections indicated also that emergent fluxes and line profiles of rotationally distorted stars can be matched by the predictations of standard model atmospheres to a very high accuray, even for w close to unity (Wenske 1992, Diplom Thesis).

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Lorenzo-Gutiérrez, A., E. J. Alfaro, J. Maíz Apellániz, R. H. Barbá, A. Marín-Franch, A. Ederoclite, D. Cristóbal-Hornillos, et al. "Deriving stellar parameters from GALANTE photometry: bias and precision." Monthly Notices of the Royal Astronomical Society 494, no. 3 (April 9, 2020): 3342–57. http://dx.doi.org/10.1093/mnras/staa892.

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ABSTRACT In this paper, we analyse how to extract the physical properties from the GALANTE photometry of a stellar sample. We propose a direct comparison between the observational colours (photometric bands normalized to the 515 nm central wavelength) and the synthetic colours derived from different stellar libraries. We use the reduced χ2 as the figure of merit for selecting the best fitting between both colour sets. The synthetic colours of the Next Generation Spectral Library (NGSL) provide a valuable sample for testing the uncertainty and precision of the stellar parameters derived from observational data. Reddening, as an extrinsic stellar physical parameter becomes a crucial variable for accounting for the errors and bias in the derived estimates: the higher the reddenings, the larger the errors and uncertainties in the derived parameters. NGSL colours also enable us to compare different theoretical stellar libraries for the same set of physical parameters, where we see how different catalogues of models can provide very different solutions in a, sometimes, non-linear way. This peculiar behaviour makes us to be cautious with the derived physical parameters obtained from GALANTE photometry without previous detailed knowledge of the theoretical libraries used to this end. In addition, we carry out the experiment of deriving physical stellar parameters from some theoretical libraries, using some other libraries as observational data. In particular, we use the Kurucz and Coelho libraries, as input observational data, to derive stellar parameters from Coelho + TLUSTY and Kurucz + TLUSTY stellar libraries, respectively, for different photometric errors and colour excesses.

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Deacon, N. R., Th Henning, and D. E. Kossakowski. "Data-driven stellar parameters for southern TESS FGK targets." Monthly Notices of the Royal Astronomical Society 486, no. 1 (March 19, 2019): 251–65. http://dx.doi.org/10.1093/mnras/stz722.

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Abstract We present stellar parameter estimates for 939 457 southern FGK stars that are candidate targets for the Transiting Exoplanet Survey Satellite (TESS) mission. Using a data-driven method similar to the CANNON, we build a model of stellar colours as a function of stellar parameters. We then use these in combination with stellar evolution models to estimate the effective temperature, gravity, metallicity, mass, radius, and extinction for our selected targets. Our effective temperature estimates compare well with those from spectroscopic surveys and the addition of Gaia DR2 parallaxes allows us to identify subgiant interlopers into the TESS sample. We are able to estimate the radii of TESS targets with a typical uncertainty of 9.3 per cent. This catalogue can be used to screen exoplanet candidates from TESS and provides a homogeneous set of stellar parameters for statistical studies.

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20

Ness, Melissa K., Victor Silva Aguirre, Mikkel N. Lund, Matteo Cantiello, Daniel Foreman-Mackey, David W. Hogg, and Ruth Angus. "Inference of Stellar Parameters from Brightness Variations." Astrophysical Journal 866, no. 1 (October 5, 2018): 15. http://dx.doi.org/10.3847/1538-4357/aadb40.

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21

Schmutz, Werner, and Orsola De Marco. "Revised stellar parameters of Wolf-Rayet stars." Symposium - International Astronomical Union 193 (1999): 147–56. http://dx.doi.org/10.1017/s0074180900205251.

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We discuss the reliability of the stellar parameters derived from spectroscopic analyses with atmosphere models. We follow the revisions of the stellar parameters of a WN4b star through improvements of the model codes carried out in the last ten years. In order to judge the reliability of the current results we have started to analyze binaries for which the mass of the WR star is known and therefore its luminosity can be derived from the theoretical mass-luminosity relation. Along this line, we present preliminary results from work in progress on the binary γ2 Velorum.

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22

Malavolta, L., C. Lovis, F. Pepe, C. Sneden, and S. Udry. "Atmospheric stellar parameters from cross-correlation functions." Monthly Notices of the Royal Astronomical Society 469, no. 4 (May 8, 2017): 3965–75. http://dx.doi.org/10.1093/mnras/stx1100.

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23

Gustafsson, Bengt, and Uffe Graae-Jørgensen. "Fundamental Parameters and Models of Stellar Atmospheres." Symposium - International Astronomical Union 111 (1985): 303–29. http://dx.doi.org/10.1017/s0074180900078918.

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The use of photometric and spectroscopic criteria, calibrated by model-atmosphere calculations, for determining effective temperatures, surface gravities and chemical compositions of stars is illustrated and commented on. The accuracy that can be obtained today in such calibrations is discussed, as well as possible ways of improving this accuracy further for different types of stars.

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Wu, Yue, H. P. Singh, P. Prugniel, R. Gupta, and M. Koleva. "Coudé-feed stellar spectral library – atmospheric parameters." Astronomy & Astrophysics 525 (December 2, 2010): A71. http://dx.doi.org/10.1051/0004-6361/201015014.

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25

Frasca, A., J. Molenda-Żakowicz, P. De Cat, G. Catanzaro, J. N. Fu, A. B. Ren, A. L. Luo, J. R. Shi, Y. Wu, and H. T. Zhang. "Activity indicators and stellar parameters of theKeplertargets." Astronomy & Astrophysics 594 (October 2016): A39. http://dx.doi.org/10.1051/0004-6361/201628337.

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26

Kupriyanova, Elena, Dmitrii Kolotkov, Valery Nakariakov, and Anastasiia Kaufman. "QUASI-PERIODIC PULSATIONS IN SOLAR AND STELLAR FLARES. REVIEW." Solar-Terrestrial Physics 6, no. 1 (April 1, 2020): 3–23. http://dx.doi.org/10.12737/stp-61202001.

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This paper provides an overview of the state-of-the-art studies of oscillatory processes in solar and stellar flares, based on modern observational data from ground-based and space-borne instruments with high temporal, spatial, and spectral resolution in different bands of the electromagnetic spectrum. We examine the mecha-nisms that generate flare emission and its quasi-periodic modulation. We discuss similarities and differences be-tween solar and stellar flares, and address associated problems of superflares on the Sun and space weather. Quasi-periodic pulsations (QPPs) of flare emission are shown to be an effective tool for diagnosing both the flare processes themselves and the parameters of flaring plasmas and accelerated particles. We consider types of QPPs, their statistical properties, and methods of analysis, taking into account the non-stationarity of the QPPs’ parameters. We review the proposed mechanisms of QPPs and summarize open questions.

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27

Däppen, Werner. "Stellar Seismology." International Astronomical Union Colloquium 121 (1990): 357–70. http://dx.doi.org/10.1017/s0252921100068068.

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AbstractStellar acoustic oscillation frequencies will likely be accurately observed in the near future, in analogy to the well-known solar five-minute oscillation frequencies. Of course, we will never expect the wealth of solar data, which is a result of spatial resolution. We will therefore not be able to solve the inverse problem, that is to probe physical quantities as functions of depth, and the low number of anticipated observed frequencies will make an unambiguous mode identification difficult. Despite this restriction to the forward problem, however, observed stellar oscillation frequencies will become valuable constraints for the determination of stellar parameters. One should not forget that the present knowledge of stellar ages and compositions relies on the calibration of theoretical models (matching effective temperature and luminosity). Additional observational constraints will improve these calibrations, even if the theoretical models themselves are not questioned. We hope, however, that the observation of stellar oscillation frequencies will also lead to improvements in the physics of stellar models, in analogy to the solar case. Again, of course, stellar seismologists will be less ambitious than helioseismologists, since there are more open parameters in stellar models. However, stellar observations will allow tests of models with different age and composition.

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28

Butkevich, A. G., A. V. Berdyugin, and P. Teerikorpi. "Calibration of stellar parameters using high-precision parallaxes." Proceedings of the International Astronomical Union 3, S248 (October 2007): 488–89. http://dx.doi.org/10.1017/s1743921308019881.

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AbstractUtilization of sub-milliarcsecond trigonometric parallaxes shifts the classical problem of calibration of stellar parameters to a new level of complexity. Derivation of stellar luminosity from the parallaxes is not a straightforward task with a number of statistical effects, such as Malmquist bias, to be taken into account. Different methods are to be used in order to derive parameters of luminosity function depending on the nature of underlying stellar sample. It is emphasized that any combination of astrometric parameters (i.e. parallaxes) and astrophysical ones must be handled carefully to avoid or reduce statistical effects, which otherwise may seriously affect the astrophysical applications.

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Le Coroller, H., D. Gillet, A. B. Fokin, and A. Lèbre. "Stellar Parameters of the Post-AGB Star HD 56126." International Astronomical Union Colloquium 185 (2002): 578–79. http://dx.doi.org/10.1017/s0252921100017140.

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AbstractWe discuss the stellar parameters (M, L, Teff) of a post-AGB star, HD 56126, deduced from observations and non-linear radiative pulsation models. We show that pure radiative pulsation models are in contrast with stellar evolution.

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Pérez-Rendón, Brenda, Horacio Pineda-León, Alfredo Santillán, and Liliana Hernández-Cervantes. "Evolutionary effects of stellar rotation of massive stars in their pre-supernova environments." Proceedings of the International Astronomical Union 6, S272 (July 2010): 99–100. http://dx.doi.org/10.1017/s174392131101009x.

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AbstractMassive main sequence stars are fast rotators. Stellar rotation affects massive stellar rotation due to rotationally induced mixing processes, the increase of mass loss rates, etc. and also affects the circumstellar medium due to their interaction with the stellar wind. The parameters of stellar winds depends on stellar parameters so the wind parameters change as the star evolves, coupling the evolution of circumstellar medium to the star itself. In this work we used a stellar code to build models of two massive stars (30 and 40 M⊙) and we used their wind parameters to simulate the hydrodynamics of their surrounding gas with the ZEUS-3D code in order to explore the effects of stellar rotation in the pre-supernova environments.

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Jørgensen, Andreas Christ Sølvsten, and George C. Angelou. "Bayesian inference of stellar parameters based on 1D stellar models coupled with 3D envelopes." Monthly Notices of the Royal Astronomical Society 490, no. 2 (October 10, 2019): 2890–904. http://dx.doi.org/10.1093/mnras/stz2825.

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ABSTRACT Stellar models utilizing 1D, heuristic theories of convection fail to adequately describe the energy transport in superadiabatic layers. The improper modelling leads to well-known discrepancies between observed and predicted oscillation frequencies for stars with convective envelopes. Recently, 3D hydrodynamic simulations of stellar envelopes have been shown to facilitate a realistic depiction of superadiabatic convection in 1D stellar models. The resulting structural changes of the boundary layers have been demonstrated to impact not only the predicted oscillation spectra but evolution tracks as well. In this paper, we quantify the consequences that the change in boundary conditions has for stellar parameter estimates of main-sequence stars. For this purpose, we investigate two benchmark stars, Alpha Centauri A and B, using Bayesian inference. We show that the improved treatment of turbulent convection makes the obtained 1D stellar structures nearly insensitive to the mixing length parameter. By using 3D simulations in 1D stellar models, we hence overcome the degeneracy between the mixing length parameter and other stellar parameters. By lifting this degeneracy, the inclusion of 3D simulations has the potential to yield more robust parameter estimates. In this way, a more realistic depiction of superadiabatic convection has important implications for any field that relies on stellar models, including the study of the chemical evolution of the Milky Way Galaxy and exoplanet research.

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32

Ledinauskas, Eimantas, and Kastytis Zubovas. "Evolution of dwarf galaxy observable parameters." Monthly Notices of the Royal Astronomical Society 493, no. 1 (February 6, 2020): 638–50. http://dx.doi.org/10.1093/mnras/staa298.

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ABSTRACT We present a semi-analytic model of isolated dwarf galaxy evolution and use it to study the build-up of observed correlations between dwarf galaxy properties. We analyse the evolution using models with averaged and individual halo mass assembly histories in order to determine the importance of stochasticity on the present-day properties of dwarf galaxies. The model has a few free parameters, but when these are calibrated using the halo mass–stellar mass and stellar mass–metallicity relations, the results agree with other observed dwarf galaxy properties remarkably well. Redshift evolution shows that even isolated galaxies change significantly over the Hubble time and that ‘fossil dwarf galaxies’ with properties equivalent to those of high-redshift analogues should be extremely rare, or non-existent, in the local Universe. A break in most galaxy property correlations develops over time, at a stellar mass $M_* \simeq 10^7 \, {\rm M_{\odot }}$. It is caused predominantly by the ionizing background radiation and can therefore in principle be used to constrain the properties of reionization.

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Neilson, Hilding R., Fabien Baron, Ryan Norris, Brian Kloppenborg, and John B. Lester. "STELLAR ATMOSPHERES, ATMOSPHERIC EXTENSION, AND FUNDAMENTAL PARAMETERS: WEIGHING STARS USING THE STELLAR MASS INDEX." Astrophysical Journal 830, no. 2 (October 17, 2016): 103. http://dx.doi.org/10.3847/0004-637x/830/2/103.

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Percival, Susan M., and Maurizio Salaris. "THE IMPACT OF SYSTEMATIC UNCERTAINTIES IN STELLAR PARAMETERS ON INTEGRATED SPECTRA OF STELLAR POPULATIONS." Astrophysical Journal 703, no. 1 (September 4, 2009): 1123–30. http://dx.doi.org/10.1088/0004-637x/703/1/1123.

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Wang, Liang, Yujuan Liu, Gang Zhao, and Bun'ei Sato. "Stellar Parameters and Chemical Abundances of G Giants." Publications of the Astronomical Society of Japan 63, no. 5 (October 25, 2011): 1035–46. http://dx.doi.org/10.1093/pasj/63.5.1035.

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Kassounian, Sarkis, Marwan Gebran, Frédéric Paletou, and Victor Watson. "Sliced Inverse Regression: application to fundamental stellar parameters." Open Astronomy 28, no. 1 (May 11, 2019): 68–84. http://dx.doi.org/10.1515/astro-2019-0006.

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AbstractWe present a method for deriving the stellar fundamental parameters. It is based on a regularized sliced inverse regression (RSIR).We first tested it on noisy synthetic spectra of A, F, G, and K-type stars, and inverted simultaneously their atmospheric fundamental parameters: Teff., log g, [M/H] and v sin i. Different learning databases were calculated using a range of sampling in Teff., log g, v sin i, and [M/H]. Combined with a principal component analysis (PCA) nearest neighbors (NN) search, the size of the learning database is reduced. A Tikhonov regularization is applied, given the ill-conditioning of SIR. For all spectral types, decreasing the size of the learning database allowed us to reach internal accuracies better than PCA-based NN-search using larger learning databases. For each analyzed parameter, we have reached internal errors that are smaller than the sampling step of the parameter. We have also applied the technique to a sample of observed FGK and A stars. For a selection of well-studied stars, the inverted parameters are in agreement with the ones derived in previous studies. The RSIR inversion technique, complemented with PCA pre-processing proves to be efficient in estimating stellar parameters of A, F, G, and K-type stars.

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Barbuy, B., S. Ortolani, E. Bica, A. Renzini, and M. D. Guarnieri. "Stellar parameters in the bulge cluster NGC 6553." Symposium - International Astronomical Union 189 (1997): 203–6. http://dx.doi.org/10.1017/s0074180900116699.

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Globular clusters in the Galactic bulge form a flattened system, extending from the Galactic center to about 4.5 kpc from the Sun (Barbuy et al. 1997). A study of abundance ratios in these clusters is very important for a more complete understanding of the bulge formation. In this work we present a spectroscopic analysis of individual stars in NGC 6553. This cluster is a key one because it is located at d⊙ ≍ 5.1 kpc, therefore relatively close to us, and at the same time it is representative of the Galactic bulge stellar population: (a) Ortolani et al. (1995) showed that NGC 6553 and NGC 6528 show very similar Colour-Magnitude Diagrams (CMDs), and NGC 6528 is located at d⊙ ≍ 7.83 kpc, very close to the Galactic center; (b) the stellar populations of the Baade Window is also very similar to that of NGC 6553 and NGC 6528 as Ortolani et al. (1995) have shown by comparing their luminosity functions.

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Liu, Chuan-Xing, Pei-Ai Zhang, and Yu Lu. "Estimating stellar atmospheric parameters based on Lasso features." Research in Astronomy and Astrophysics 14, no. 4 (March 26, 2014): 423–32. http://dx.doi.org/10.1088/1674-4527/14/4/005.

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Bellinger, Earl P., George C. Angelou, Saskia Hekker, Sarbani Basu, Warrick H. Ball, and Elisabet Guggenberger. "Stellar Parameters in an Instant with Machine Learning." EPJ Web of Conferences 160 (2017): 05003. http://dx.doi.org/10.1051/epjconf/201716005003.

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40

Granzer, T. "Relations between star-spot distribution and stellar parameters." Astronomische Nachrichten 323, no. 3-4 (August 2002): 395–98. http://dx.doi.org/10.1002/1521-3994(200208)323:3/4<395::aid-asna395>3.0.co;2-a.

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Martins, F. "Atmosphere models and the determination of stellar parameters." EAS Publications Series 65 (2014): 75–98. http://dx.doi.org/10.1051/eas/1465003.

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Sichevskij, S. G., A. V. Mironov, and O. Yu Malkov. "Accuracy of stellar parameters determined from multicolor photometry." Astrophysical Bulletin 69, no. 2 (April 2014): 160–68. http://dx.doi.org/10.1134/s1990341314020035.

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Jardine, M., A. A. Vidotto, and V. See. "Estimating stellar wind parameters from low-resolution magnetograms." Monthly Notices of the Royal Astronomical Society: Letters 465, no. 1 (October 5, 2016): L25—L29. http://dx.doi.org/10.1093/mnrasl/slw206.

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Ibragimov, A. A., V. F. Suleimanov, A. Vikhlinin, and N. A. Sakhibullin. "Supersoft X-ray sources. parameters of stellar atmospheres." Astronomy Reports 47, no. 3 (March 2003): 186–96. http://dx.doi.org/10.1134/1.1562213.

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Repolust, T., J. Puls, and A. Herrero. "Stellar and wind parameters of Galactic O-stars." Astronomy & Astrophysics 415, no. 1 (February 2004): 349–76. http://dx.doi.org/10.1051/0004-6361:20034594.

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Bach, Kiehunn, Yong-Cheol Kim, and Pierre Demarque. "CALIBRATION OF STELLAR PARAMETERS OF 85 PEG SYSTEM." Journal of Astronomy and Space Sciences 24, no. 1 (March 10, 2007): 31–38. http://dx.doi.org/10.5140/jass.2007.24.1.031.

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Terlevich, Elena, Angeles I. D�az, and Roberto Terlevich. "Stellar atmospheric parameters and the IR Caii triplet." Astrophysics and Space Science 157, no. 1-2 (1989): 15–21. http://dx.doi.org/10.1007/bf00637305.

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Griffin, R. E. M., and Slavek Rucinski. "Binarity and Stellar Evolution." Proceedings of the International Astronomical Union 7, S285 (September 2011): 239–42. http://dx.doi.org/10.1017/s174392131200066x.

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AbstractModels of stellar evolution constitute an extremely powerful, and for the most part apparently very successful, tool for understanding the progression of a star through its lifetime as a fairly compact entity of incandescent gas. That success has led to stellar evolution theory becoming a crutch when an observer is faced with objects whose provenance or current state are in some way puzzling, but how safe a crutch? The validity of the theory is best checked by examining binary systems whose component parameters have been determined with high precision, but it can be (and needs to be) honed through the many challenges which non-conformist single stars and triple systems also present. Unfortunately the lever of observational parameters to constrain or challenge stellar evolution theory is not as powerful as it could be, because not all determinations of stellar parameters for the same systems agree to within the precisions claimed by their respective authors. What are the sources of bias—the data, the instrument or the techniques? The workshop was invited to discuss particularly challenging cases, and to attempt to identify how and where progress might be pursued.

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Montalbán, J., A. Bressan, L. Girardi, T. Rodrigues, D. Bossini, A. Miglio, R. Scuflaire, M. Trabucchi, and P. Marigo. "PARSEC evolutionary tracks and isochrones including seismic properties." Proceedings of the International Astronomical Union 13, S334 (July 2017): 343–44. http://dx.doi.org/10.1017/s1743921317007554.

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AbstractIn the recent years it has been generally accepted that seismic parameters add an important observational constraint for the study of stellar populations and galaxy evolution. Padova-Trieste (PARSEC) evolutionary tracks are widely used to characterise stellar objects and stellar populations. Stellar models at the base of these studies suffer from uncertainties and, more important, degeneracy among different input parameters: stellar mass, chemical composition, central chemical mixing, age, etc. Adding seismic properties to the classic parameters for stars at different evolutionary states, from the H main-sequence to the asymptotic giant branch, is a powerful tool to calibrate physical processes in stellar models, and hence to improve our interpretation of Galactic and extra-Galactic observations.

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Nataf, David M. "The relationship between globular cluster parameters and abundance variations." Proceedings of the International Astronomical Union 14, S351 (May 2019): 333–36. http://dx.doi.org/10.1017/s1743921319007488.

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AbstractWe discuss a meta-analysis of the association of abundance variations in globular cluster stars with the present-day stellar mass and metallicity of globular clusters. Using data for 42 globular clusters that are well-sampled from either or both of prior literature studies and the APOGEE survey, we confirm prior findings that increasing aluminum abundance variations in globular clusters are positively correlated with increasing present-day stellar mass or decreasing metallicity. We also demonstrate that the ratio of aluminum abundance variations to either nitrogen abundance variations or sodium abundance variations is itself positively correlated with decreasing metallicity and increasing stellar mass of globular clusters. This suggests that there were at least two non-supernovae chemical polluters that were active in the early universe.

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