Results 111 to 120 of about 12,408 (264)

Oxygen and Nitrogen in Isolated Dwarf Irregular Galaxies

The Astrophysical Journal, 2006
We present long slit optical spectroscopy of 67 HII regions in 21 dwarf irregular galaxies to investigate the enrichment of oxygen, nitrogen, neon, sulfur, and argon in low mass galaxies. Oxygen abundances are obtained via direct detection of the temperature sensitive emission lines for 25 HII regions; for the remainder of the sample, oxygen abundances
van Zee, L., Haynes, M. P.
openaire   +2 more sources

Discovery of Metal-poor and Distant Pre–Main Sequence Candidates in WLM with JWST

The Astrophysical Journal Letters
We present the discovery of 12 metal-poor and ​​​distant pre–main sequence (PMS) candidates in the dwarf irregular galaxy Wolf–Lundmark–Melotte ∼968 kpc away, at a present-day metallicity of [Fe/H] ∼ –0.9.
Venu M. Kalari, Ricardo Salinas, Morten Andersen, Guido De Marchi, Monica Rubio, Jorick S. Vink, Hans Zinnecker   +6 more
doaj   +1 more source

Extended Schmidt law holds for faint dwarf irregular galaxies

, 2017
The extended Schmidt law (ESL) is a variant of the Schmidt law which relates the surface densities of gas and star formation, with the surface density of stellar mass added as an extra parameter.
Chengalur, Jayaram N., Roychowdhury, Sambit, Shi, Yong   +2 more
core   +1 more source

The Local Ultraviolet to Infrared Treasury. II. Refining Star Formation Histories of 10 Metal-poor Dwarf Galaxies with Simultaneous UV-optical Two-CMD Fitting

The Astronomical Journal
We present the star formation histories (SFHs) of 10 metal-poor (≲12% Z _⊙ ), star-forming dwarf galaxies from the Local Ultraviolet to Infrared Treasury survey.
Yumi Choi, Karoline M. Gilbert, Benjamin F. Williams, Daniel R. Weisz, Evan D. Skillman, Julianne J. Dalcanton, Kristen B. W. McQuinn, Andrew E. Dolphin, Giada Pastorelli, Martha L. Boyer, Karl D. Gordon, Léo Girardi, Maude Gull   +12 more
doaj   +1 more source

87th Annual Meeting of the Meteoritical Society 2025: Abstracts

Meteoritics &Planetary Science, Volume 60, Issue S1, Page 30-350, August 2025.
wiley   +1 more source

Chemical Properties of Star-Forming Emission Line Galaxies at z=0.1 - 0.5

, 1998
We measure oxygen and nitrogen abundances for 14 star-forming emission line galaxies (ELGs) at 0 ...
Bender R., Davies J. I., Dennis Zaritsky, Edmunds M. G., Henry A. Kobulnicky, Howarth I. D., Hummer D. G., Larson R. B., Lequeux J., Madau P., Mateo M., Pagel B. E. J., Pagel B. E. J., Pagel B. E. J., Pagel B. E. J., Renzini A., Rix H. W., Schneider D. P., Seaton M. J., Telles E., Telles E., Terlevich R., van Zee L.   +22 more
core   +3 more sources

A γ-Ray-emitting Collisional Ring Galaxy System in Our Galactic Neighborhood

The Astrophysical Journal Letters
The astrophysical γ -ray photons carry the signatures of the violent phenomena happening on various astronomical scales in our Universe. This includes supernova remnants, pulsars, and pulsar wind nebulae in the Galactic environment and extragalactic ...
Vaidehi S. Paliya, D. J. Saikia
doaj   +1 more source

The Interstellar Medium in Dwarf Irregular Galaxies

Annual Review of Astronomy and Astrophysics
Dwarf irregular (dIrr) galaxies are among the most common type of galaxy in the Universe. They typically have gas-rich, low-surface-brightness, metal-poor, and relatively thick disks. Here, we summarize the current state of our knowledge of the interstellar medium (ISM), including atomic, molecular, and ionized gas, along with their dust properties and
Hunter, Deidre A., Elmegreen, Bruce G., Madden, Suzanne C.   +2 more
openaire   +3 more sources

What Does the LMC Look Like? It Depends on [M/H] and Age

The Astrophysical Journal
We offer a new way to look at the LMC through stellar mono-abundance and mono-age mono-abundance maps. These maps are based on ≳500,000 member stars with estimates of [M/H] ( σ _[M/H]  ~ 0.17) and age $({\sigma }_{{\rm{log}}\tau }\unicode{x0007E}0.15$ ),
Neige Frankel, Rene Andrae, Hans-Walter Rix, Joshua Povick, Vedant Chandra   +4 more
doaj   +1 more source

Cosmic ray feedback in galaxies and galaxy clusters: A pedagogical introduction and a topical review of the acceleration, transport, observables, and dynamical impact of cosmic rays. [PDF]

Astron Astrophys Rev, 2023
Ruszkowski M, Pfrommer C.
europepmc   +1 more source