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The ramp-up of interstellar medium enrichment at z>4
(2021-11-04)
Fluorine is one of the most interesting elements for nuclear and stellar astrophysics 1,2. Fluorine abundance was first measured for stars other than the Sun in 1992 1, then for a handful of metal-poor stars 3, which are ...
High resolution spectroscopic follow-up of the most metal-poor candidates from SkyMapper DR1.1
(2021-11-01)
We present chemical abundances for 21 elements (from Li to Eu) in 150 metal-poor Galactic stars spanning -4.1 < [Fe/H] < -2.1. The targets were selected from the SkyMapper survey and include 90 objects with [Fe/H] ≤ -3 of ...
Barium lines in high-quality spectra of two metal-poor giants in the Galactic halo
(2021-10-01)
Context. Theoretical results showed the possibility that neutron capture elements were produced in the early Universe by two different sources: a frequent s-process source hosted by rotating massive stars, and a rare ...
Herschel Photometric Observations of LITTLE THINGS Dwarf Galaxies
(2021-08-02)
We present here far-infrared photometry of galaxies in a sample that is relatively unexplored at these wavelengths: low-metallicity dwarf galaxies with moderate star formation rates. Four dwarf irregular galaxies from the ...
Introducing the NewHorizon simulation : Galaxy properties with resolved internal dynamics across cosmic time
(2021-07-28)
Hydrodynamical cosmological simulations are increasing their level of realism by considering more physical processes and having greater resolution or larger statistics. However, usually either the statistical power of such ...
Variable stars in the VVV globular clusters. II. NGC6441, NGC6569, NGC6626 (M28), NGC6656 (M22), 2MASS-GC02, and Terzan10
(2021-07-12)
Context. The Galactic globular clusters (GGCs) located in the inner regions of the Milky Way suffer from high extinction that makes their observation challenging. High densities of field stars in their surroundings complicate ...
Cosmic evolution of the H2 mass density and the epoch of molecular gas
(2021-05-05)
We present new empirical constraints on the evolution of ρ H2, the cosmological mass density of molecular hydrogen, back to z ≈ 2.5. We employ a statistical approach measuring the average observed 850 μm flux density of ...
Can the Local Bubble explain the radio background?
(2021-04-01)
The ARCADE 2 balloon bolometer along with a number of other instruments have detected what appears to be a radio synchrotron background at frequencies below about 3 GHz. Neither extragalactic radio sources nor diffuse ...
Dust polarized emission observations of NGC 6334 : BISTRO reveals the details of the complex but organized magnetic field structure of the high-mass star-forming hub-filament network
(2021-03-11)
Context. Molecular filaments and hubs have received special attention recently thanks to new studies showing their key role in star formation. While the (column) density and velocity structures of both filaments and hubs ...
AstroVaDEr: Astronomical Variational Deep Embedder for Unsupervised Morphological Classification of Galaxies and Synthetic Image Generation
(2021-03-01)
We present AstroVaDEr (Astronomical Variational Deep Embedder), a variational autoencoder designed to perform unsupervised clustering and synthetic image generation using astronomical imaging catalogues. The model is a ...