Results 1 to 10 of about 11,182,421 (303)

Variable stars in Galactic globular clusters

Astronomy & Astrophysics
We identified a sample of 88 bona fide Population II Cepheids (henceforth referred to as Cepheids) and 44 candidates in Galactic globular clusters (GCs). Seventy-eight of the Cepheids in the sample align within 2 σ of the period-luminosity relation for Milky Way Type II Cepheids (T2CEPs).
Mauricio Cruz Reyes, Richard I. Anderson, Susmita Das   +2 more
openaire   +3 more sources

A Metallicity Catalog of Very Metal-poor Main-sequence Turn-off and Red Giant Stars from LAMOST DR10

The Astrophysical Journal Supplement Series
We present a catalog of 8440 candidate very metal-poor (VMP; [Fe/H] ≤ −2.0) main-sequence turn-off (MSTO) and red giant stars in the Milky Way, identified from low-resolution spectra in LAMOST DR10. More than 7000 of these candidates are brighter than G  
Xiangyu Li, Huiling Chen, Yang Huang, Huawei Zhang, Timothy C. Beers, Linxuan Zhu, Jifeng Liu   +6 more
doaj   +1 more source

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

A joint 1% calibration of the RR Lyrae and type-II Cepheid Leavitt laws yields homogeneous distances to 93 Galactic globular clusters

Astronomy & Astrophysics
Recent work has established large samples of astrometrically confirmed RR Lyrae and type-II Cepheid members of Galactic globular clusters (GCs). Any given GC can contain multiple such stars at once, notably RR Lyrae stars pulsating in the fundamental ...
Lengen Bastian, Anderson Richard I., Cruz Reyes Mauricio, Viviani Giordano   +3 more
doaj   +1 more source

New Perspective on the Multiple-population Phenomenon in Galactic Globular Clusters from a Wide-field Photometric Survey

The Astrophysical Journal
Wide-field photometry of Galactic globular clusters (GCs) has been investigated to overcome limitations from the small field of view of the Hubble Space Telescope in the study of multiple populations.
S. Jang, A. P. Milone, A. F. Marino, M. Tailo, E. Dondoglio, M. V. Legnardi, G. Cordoni, T. Ziliotto, E. P. Lagioia, M. Carlos, A. Mohandasan, E. Bortolan, Y.-W. Lee   +12 more
doaj   +1 more source

Extended Stellar Populations in Ultrafaint Dwarf Galaxies

The Astronomical Journal
The possible existence of stellar halos in low-mass galaxies is being intensely discussed nowadays after some recent discoveries of stars located in the outskirts of dwarf galaxies of the Local Group.
Elisa A. Tau, A. Katherina Vivas, Clara E. Martínez-Vázquez   +2 more
doaj   +1 more source

Observational signatures and constraints on the intermediate neutron-capture process

Astronomy & Astrophysics
Context. Observational abundances of carbon enhanced metal-Poor (CEMP) stars with patterns in between those produced by the rapid (r) and slow (s) nucleosynthesis processes (CEMP-rs stars) are currently invoked as evidence of synthesis via the ...
Giribaldi R. E., Vescovi D., Magrini L., Cristallo S., D’Orazi V., Piersanti L., Cornejo Espinoza D., Randich S., Baratella M.   +8 more
doaj   +1 more source

Spectacular Nucleosynthesis from Early Massive Stars

The Astrophysical Journal Letters
Stars that formed with an initial mass of over 50 M _⊙ are very rare today, but they are thought to be more common in the early Universe. The fates of those early, metal-poor, massive stars are highly uncertain.
Alexander P. Ji, Sanjana Curtis, Nicholas Storm, Vedant Chandra, Kevin C. Schlaufman, Keivan G. Stassun, Alexander Heger, Marco Pignatari, Adrian M. Price-Whelan, Maria Bergemann, Guy S. Stringfellow, Carla Fröhlich, Henrique Reggiani, Erika M. Holmbeck, Jamie Tayar, Shivani P. Shah, Emily J. Griffith, Chervin F. P. Laporte, Andrew R. Casey, Keith Hawkins, Danny Horta, William Cerny, Pierre Thibodeaux, Sam A. Usman, João A. S. Amarante, Rachael L. Beaton, Phillip A. Cargile, Cristina Chiappini, Charlie Conroy, Jennifer A. Johnson, Juna A. Kollmeier, Haining Li, Sarah Loebman, Georges Meynet, Dmitry Bizyaev, Joel R. Brownstein, Pramod Gupta, Sean Morrison, Kaike Pan, Solange V. Ramirez, Hans-Walter Rix, José Sánchez-Gallego   +41 more
doaj   +1 more source

Hidden Population III Descendants in Ultrafaint Dwarf Galaxies

The Astrophysical Journal
The elusive properties of the first (Population III or Pop III) stars can be indirectly unveiled by uncovering their true descendants. To this end, we exploit our data-calibrated model for the best-studied ultrafaint dwarf galaxy (UFD), Boötes I, which ...
Martina Rossi, Stefania Salvadori, Ása Skúladóttir, Irene Vanni, Ioanna Koutsouridou   +4 more
doaj   +1 more source

Investigation of high-quality spectra of a sample of high-radial-velocity stars★

Astronomy & Astrophysics
Context. Old, metal-poor stars are perfect tracers of the formation of the Milky Way. The combination of chemical and kinematic investigations into them provides an insight into accretion episodes in the past history of our Galaxy. Aims.
Alazzawi J. M. K., Caffau E., Bonifacio P., Çalışkan Ş., Monaco L., Sbordone L., Lombardo L.   +6 more
doaj   +1 more source