Results 61 to 70 of about 462 (193)

An Enhanced Hertzsprung–Russell Diagram Using Gaia EDR3 Data

, 2021
Wei‐Chun Jao, Gregory A. Feiden
openalex   +1 more source

An AGN Hertzsprung-Russell Diagram

, 2002
Contribution for Elba Conference "Issues in Unification of AGNs"
openaire   +3 more sources

Theoretical interpretation of the Hertzsprung-Russell diagram [PDF]

Symposium - International Astronomical Union, 1959
The theory of the stellar interior indicates that for a star of given mass, given initial composition, and given age, all physical characteristics (including the luminosity and the effective temperature) are uniquely determined. Accordingly it should be possible to derive theoretically for a particular star of definite mass and initial composition a ...
openaire   +1 more source

Stellar X-Ray Activity Across the Hertzsprung–Russell Diagram. I. Catalogs [PDF]

, 2020
Song Wang, Yu Bai, Lin He, Jifeng Liu
openalex   +1 more source

A Comprehensive Study of Czernik 41 and NGC 1342 Using CCD UBV and Gaia DR3 Data

The Astronomical Journal
In this study, the structural, astrophysical, kinematic, and Galactic orbital parameters of the open clusters Czernik 41 and NGC 1342, as well as their dynamical evolution, are investigated using CCD UBV photometry and Gaia data.
Burçin Tanık Öztürk, Selçuk Bilir, Talar Yontan, Olcay Plevne, Tansel Ak, Serap Ak, Remziye Canbay, Timothy Banks   +7 more
doaj   +1 more source

Evaluating Gaia Astrometric Quality and Distances for Galactic Hot Supergiants

Universe
Distances to Galactic BA supergiants are essential for determining their luminosities, radii, and positions on the Hertzsprung–Russell diagram, yet Gaia parallaxes for these bright, extended sources are often affected by systematics.
Nadezhda L. Vaidman, Shakhida T. Nurmakhametova, Aziza B. Umirova, Serik A. Khokhlov, Aldiyar T. Agishev, Berik S. Yermekbayev   +5 more
doaj   +1 more source

The HIPPARCOS Hertzsprung-Russell diagram of S stars: Probing\n nucleosynthesis and dredge-up [PDF]

, 1997
S. Van Eck, A. Jorissen, S. Udry, M. Mayor, B. Pernier   +4 more
openalex   +2 more sources

Hα Emission among Evolved FGKM Stars: A Compendium from the Literature

The Astronomical Journal
Emission in the wings of the H α line among late-type giant stars occurs as a consequence of conditions in their chromospheres. Data from the literature have been used to document the incidence of H α emission among Population I giant stars as a function
Graeme H. Smith
doaj   +1 more source

The Internal Kinematics of NGC 2808 and Its Multiple Populations

The Astrophysical Journal
We use new Hubble Space Telescope observations coupled with archival data spanning a total temporal baseline of 17 yr to study the internal kinematics of the multiple populations in the globular cluster NGC 2808 from its center out to ∼8 half-light radii
M. Griggio, A. Bellini, F. I. Aros, E. Vesperini, M. Libralato, J. Anderson, H. Baumgardt, F. R. Ferraro, R. P. van der Marel, S. Raso, A. Renzini, A. Rest, R. E. Ryan Jr.   +12 more
doaj   +1 more source

The imprint of star formation on stellar pulsations. [PDF]

Nat Commun, 2022
Steindl T, Zwintz K, Vorobyov E.
europepmc   +1 more source