Results 131 to 140 of about 52,268 (222)

Chemical Components in the Virgo Overdensity and Hercules–Aquila Cloud: Hints of More than One Merger Event in GSE-like Debris

The Astrophysical Journal
Using elemental abundances for 1.26 million K giants in the Large Sky Area Multi-Object Fiber Spectroscopic Telescope DR8 value-added catalog, we analyze the chemical abundances of the Virgo Overdensity and Hercules–Aquila Cloud.
Haoyang Liu, Cuihua Du, Thomas Donlon II, Mingji Deng   +3 more
doaj   +1 more source

Iron Snails: Nonequilibrium Dynamics and Spiral Abundance Patterns

The Astrophysical Journal
Galaxies are not in a dynamical steady state: they continually undergo perturbations, e.g., from infalling dwarf galaxies and dark matter substructure. After a dynamical perturbation, stars phase mix toward a new steady state; in so doing, they generally
Neige Frankel, David W. Hogg, Scott Tremaine, Adrian Price-Whelan, Jeff Shen   +4 more
doaj   +1 more source

Modeling the Ages and Chemical Abundances of Elliptical Galaxies

The Astrophysical Journal
Spectroscopic studies of elliptical galaxies show that their stellar population ages, mean metallicity, and α enhancement traced by [Mg/Fe] all increase with galaxy stellar mass or velocity dispersion.
Nicole Marcelina Gountanis, David H. Weinberg, Aliza G. Beverage, Nathan R. Sandford, Charlie Conroy, Mariska Kriek   +5 more
doaj   +1 more source

Investigation of Substructures of the Inner Halo Using the StarGO Algorithm with APOGEE DR17

The Astrophysical Journal
We applied the Stars’ Galactic Origin algorithm in 7D space (i.e., [Fe/H], [Mg/Fe], [Al/Fe], L _z ,  J _r ,  J _z ,  E ) to analyze stars in the inner halo with APOGEE DR17.
Zhongcheng Li, Cuihua Du, Haoyang Liu, Dashuang Ye   +3 more
doaj   +1 more source

The spheroidal bulge of the Milky Way: Chemodynamically distinct from the inner-thick disc and bar

Astronomy & Astrophysics
Studying the composition and origin of the inner region of our Galaxy—the “Galactic bulge”—is crucial for understanding the formation and evolution of the Milky Way and other galaxies.
Nepal S., Chiappini C., Pérez-Villegas A., Queiroz A. B., Souza S., Steinmetz M., Anders F., Khalatyan A., Barbuy B., Guiglion G.   +9 more
doaj   +1 more source

The High-Redshift Gas-Phase Mass–Metallicity Relation in FIRE-2

The Astrophysical Journal Letters
The unprecedented infrared spectroscopic capabilities of JWST have provided high-quality interstellar medium metallicity measurements and enabled characterization of the gas-phase mass–metallicity relation (MZR) for galaxies at z ≳ 5 for the first time ...
Andrew Marszewski, Guochao Sun, Claude-André Faucher-Giguère, Christopher C. Hayward, Robert Feldmann   +4 more
doaj   +1 more source

Searching for Emission Lines at z > 11: The Role of Damped Lyα and Hints About the Escape of Ionizing Photons

The Astrophysical Journal
We describe new ultradeep James Webb Space Telescope (JWST) NIRSpec PRISM and grating spectra for the galaxies JADES-GS-z11-0 ( ${z}_{\mathrm{spec}}={11.122}_{-0.003}^{+0.005}$ ) and JADES-GS-z13-0 ( ${z}_{\mathrm{spec}}={13.20}_{-0.04}^{+0.03}$ ), the ...
Kevin N. Hainline, Francesco D’Eugenio, Peter Jakobsen, Jacopo Chevallard, Stefano Carniani, Joris Witstok, Zhiyuan Ji, Emma Curtis-Lake, Benjamin D. Johnson, Brant Robertson, Sandro Tacchella, Mirko Curti, Stephane Charlot, Jakob M. Helton, Santiago Arribas, Rachana Bhatawdekar, Andrew J. Bunker, Alex J. Cameron, Eiichi Egami, Daniel J. Eisenstein, Ryan Hausen, Nimisha Kumari, Roberto Maiolino, Pablo G. Pérez-González, Marcia Rieke, Aayush Saxena, Jan Scholtz, Renske Smit, Fengwu Sun, Christina C. Williams, Christopher N. A. Willmer, Chris Willott   +31 more
doaj   +1 more source

Carbon and Iron Deficiencies in Quiescent Galaxies at z = 1–3 from JWST-SUSPENSE: Implications for the Formation Histories of Massive Galaxies

The Astrophysical Journal
We present the stellar metallicities and multielement abundances (C, Mg, Si, Ca, Ti, Cr, and Fe) of 15 massive (log M / M _⊙ = 10.2–11.2) quiescent galaxies at z = 1–3, derived from ultradeep JWST-SUSPENSE spectra. Compared to quiescent galaxies at z ∼ 0,
Aliza G. Beverage, Martje Slob, Mariska Kriek, Charlie Conroy, Guillermo Barro, Rachel Bezanson, Gabriel Brammer, Chloe M. Cheng, Anna de Graaff, Natascha M. Förster Schreiber, Marijn Franx, Brian Lorenz, Pavel E. Mancera Piña, Danilo Marchesini, Adam Muzzin, Andrew B. Newman, Sedona H. Price, Alice E. Shapley, Mauro Stefanon, Katherine A. Suess, Pieter van Dokkum, David Weinberg, Daniel R. Weisz   +22 more
doaj   +1 more source

Classical Cepheids in the Galactic thin disk

Astronomy & Astrophysics
Classical Cepheids (CCs) have long been considered excellent tracers of the chemical evolution of the Milky Way’s young disk. We present a homogeneous, non-local thermodynamical equilibrium (NLTE) spectroscopic analysis of 401 Galactic CCs, based on 1351
Nunnari A., D’Orazi V., Fiorentino G., Braga V. F., Bono G., Fabrizio M., Jönsson H., Kudritzki R.-P., da Silva R., Bergemann M., Poggio E., Otto J. M., Baeza-Villagra K., Bragaglia A., Ceci G., Dall’Ora M., Inno L., Lardo C., Matsunaga N., Monelli M., Sánchez-Benavente M., Sneden C., Tantalo M., Thévénin F., Kovtyukh V., Di Criscienzo M., Böcek Topcu G.   +26 more
doaj   +1 more source

Radial Gradients and Intrinsic Scatter in MaNGA Galaxies

The Astrophysical Journal Supplement Series
We derive stellar population parameters and radial gradients within 0.65 R _e for spatially resolved spectra of 2968 early-type galaxies from MaNGA, spanning stellar velocity dispersions ( σ ) of 50–340 km s ^−1 .
Tathagata Pal, Guy Worthey
doaj   +1 more source