Results 1 to 10 of about 10,044,096 (256)

Elemental Abundances of the Super-Neptune WASP-107b’s Host Star Using High-resolution, Near-infrared Spectroscopy

The Astrophysical Journal, 2023
We present the first elemental abundance measurements of the K dwarf (K7V) exoplanet-host star WASP-107 using high-resolution ( R ≃45,000), near-infrared ( H - and K -band) spectra taken from Gemini-S/IGRINS.
Neda Hejazi, Ian J. M. Crossfield, Thomas Nordlander, Megan Mansfield, Diogo Souto, Emilio Marfil, David R. Coria, Jonathan Brande, Alex S. Polanski, Joseph E. Hand, Kate F. Wienke   +10 more
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The Highly Accurate Relation Between the Radius and Mass of the White Dwarf Star From Zero to Finite Temperature

Frontiers in Astronomy and Space Sciences, 2022
In this research, first considering the electron–electron interaction in the high-density Fermi electron gas at T = 0 K, this interaction causes the pressure 2/137 time less than the original value.
Ting-Hang Pei
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BVR PHOTOMETRY OF SUPERGIANT STARS IN HOLMBERG II [PDF]

Journal of Astronomy and Space Sciences, 2006
We report the photometric properties in BVR bands for the resolved bright supergiant stars in the dwarf galaxy Holmberg II. The color-magnitude diagrams and color-color diagram of 374 resolved stars indicate that the majority of the member stars are ...
Y.-J. Sohn, S. W. Chang, D.-Y. Kim, J.-W. Kim, S.-H. Kim, J.-E. Lee, J. G. Lee, J.-M. Lee, M.-Y. Lee, S.-Y. Lee, U.S. Lee, B.-K. Park, H.E. Park, I.-K. Park, W H. Park, H.-S. Yi, J.-Y. Yoon   +16 more
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33 New Stellar Angular Diameters from the NPOI, and Nearly 180 NPOI Diameters as an Ensemble

The Astronomical Journal, 2023
We present new angular diameter measurements for 33 stars from the Navy Precision Optical Interferometer, reaching uncertainties on the limb-darkened diameter of 2% or less for 21 targets.
Ellyn K. Baines, James H. Clark III, Henrique R. Schmitt, Jordan M. Stone, Kaspar von Braun   +4 more
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Abundance Analysis of Stars at Large Radius in the Sextans Dwarf Spheroidal Galaxy

The Astrophysical Journal, 2023
We present the stellar parameters and chemical abundances of 30 elements for five stars located at large radii (3.5–10.7 times the half-light radius) in the Sextans dwarf spheroidal galaxy. We selected these stars using proper motions, radial velocities,
Ian U. Roederer, Andrew B. Pace, Vinicius M. Placco, Nelson Caldwell, Sergey E. Koposov, Mario Mateo, Edward W. Olszewski, Matthew G. Walker   +7 more
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HAZMAT. IX. An Analysis of the UV and X-Ray Evolution of Low-mass Stars in the Era of Gaia

The Astrophysical Journal, 2023
Low-mass stars (≤1 M _⊙ ) are some of the best candidates for hosting planets with detectable life because of these stars’ long lifetimes and relative ratios of planet to star mass and radius.
Tyler Richey-Yowell, Evgenya L. Shkolnik, Adam C. Schneider, Sarah Peacock, Lori A. Huseby, James A. G. Jackman, Travis Barman, Ella Osby, Victoria S. Meadows   +8 more
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Coronal X-Ray Emission from Nearby, Low-mass, Exoplanet Host Stars Observed by the MUSCLES and Mega-MUSCLES HST Treasury Survey Projects

The Astronomical Journal, 2023
The high-energy X-ray and ultraviolet (UV) radiation fields of exoplanet host stars play a crucial role in controlling the atmospheric conditions and the potential habitability of exoplanets.
Alexander Brown, P. Christian Schneider, Kevin France, Cynthia S. Froning, Allison A. Youngblood, David J. Wilson, R. O. Parke Loyd, J. Sebastian Pineda, Girish M. Duvvuri, Adam F. Kowalski, Zachory K. Berta-Thompson   +10 more
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Stark Broadening and White Dwarfs

Open Astronomy, 2011
White dwarf and pre-white dwarfs are the best types of stars for the application of Stark broadening research results in astrophysics, since in the atmospheres of these stars physical conditions are very favorable for this line broadening mechanism - in ...
Dimitrijević Milan S., Kovačević Andjelka, Simić Zoran, Sahal-Bréchot Sylvie   +3 more
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The SPHINX M-dwarf Spectral Grid. I. Benchmarking New Model Atmospheres to Derive Fundamental M-dwarf Properties

The Astrophysical Journal, 2023
About 70%–80% of stars in our solar and Galactic neighborhood are M dwarfs. They span a range of low masses and temperatures relative to solar-type stars, facilitating molecule formation throughout their atmospheres.
Aishwarya R. Iyer, Michael R. Line, Philip S. Muirhead, Jonathan J. Fortney, Ehsan Gharib-Nezhad   +4 more
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Chemical Analysis of the Brightest Star of the Cetus II Ultrafaint Dwarf Galaxy Candidate

The Astrophysical Journal, 2023
We present a detailed chemical abundance analysis of the brightest star in the ultrafaint dwarf (UFD) galaxy candidate Cetus II from high-resolution Magellan/MIKE spectra.
K. B. Webber, T. T. Hansen, J. L. Marshall, J. D. Simon, A. B. Pace, B. Mutlu-Pakdil, A. Drlica-Wagner, C. E. Martínez-Vázquez, M. Aguena, S. S. Allam, O. Alves, E. Bertin, D. Brooks, A. Carnero Rosell, J. Carretero, L. N. da Costa, J. De Vicente, P. Doel, I. Ferrero, D. Friedel, J. Frieman, J. García-Bellido, G. Giannini, D. Gruen, R. A. Gruendl, S. R. Hinton, D. L. Hollowood, K. Honscheid, K. Kuehn, J. Mena-Fernández, F. Menanteau, R. Miquel, R. L. C. Ogando, M. E. S. Pereira, A. Pieres, A. A. Plazas Malagón, E. Sanchez, B. Santiago, J. Allyn Smith, M. Smith, E. Suchyta, G. Tarle, C. To, N. Weaverdyck, B. Yanny   +44 more
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