Search
Now showing items 81-90 of 453
Direct measurements of carbon and sulfur isotope ratios in the Milky Way
(2023-02-14)
With the IRAM 30-m telescope, we performed observations of the $J$ = 2-1 transitions of CS, C$^{33}$S, C$^{34}$S, C$^{36}$S, $^{13}$CS, $^{13}$C$^{33}$S, and $^{13}$C$^{34}$S as well as the $J$ = 3-2 transitions of C$^{33}$S, ...
Astraeus V: the emergence and evolution of metallicity scaling relations during the epoch of reionization
(2023-01-30)
In this work, we have implemented a detailed physical model of galaxy chemical enrichment into the ASTRAEUS (seminumerical rAdiative tranSfer coupling of galaxy formaTion and Reionization in N-body dark matter simUlationS) ...
Ultracool dwarfs in Gaia DR3
(2023-01-26)
Context. Previous Gaia data releases offered the opportunity to uncover ultracool dwarfs (UCDs) through astrometric, rather than purely photometric, selection. The most recent, the third data release (DR3), offers in ...
The Faraday Rotation Measure Grid of the LOFAR Two-metre Sky Survey: Data Release 2
(2023-01-02)
A Faraday rotation measure (RM) catalogue, or RM Grid, is a valuable resource for the study of cosmic magnetism. Using the second data release (DR2) from the LOFAR Two-metre Sky Survey (LoTSS), we have produced a catalogue ...
Discovery of 24 radio-bright quasars at $4.9 \leq z \leq6.6$ using low-frequency radio observations
(2022-12-31)
High redshift quasars ($z>5$) that also shine brightly at radio wavelengths are unique signposts of supermassive black hole activity in the early universe. However, bright radio sources at $z\ge5$ are extremely rare and ...
Extragalactic Peaked-Spectrum Radio Sources at Low-Frequencies are Young Radio Galaxies
(2022-12-20)
We present a sample of 373 peaked-spectrum (PS) sources with spectral peaks around 150 MHz, selected using a subset of the two LOw Frequency ARray (LOFAR) all-sky surveys, the LOFAR Two Meter Sky Survey and the LOFAR LBA ...
The JCMT BISTRO-2 Survey: Magnetic Fields of the Massive DR21 Filament
(2022-12-20)
We present 850 μm dust polarization observations of the massive DR21 filament from the B-fields In STar-formingRegion Observations (BISTRO) survey, using the POL-2 polarimeter and the SCUBA-2 camera on the JamesClerk Maxwell ...
The JCMT BISTRO Survey: A Spiral Magnetic Field in a Hub-filament Structure, Monoceros R2
(2022-12-10)
We present and analyze observations of polarized dust emission at 850 $\mu$m towards the central 1 pc $\times$ 1 pc hub-filament structure of Monoceros R2 (Mon R2). The data are obtained with SCUBA-2/POL-2 on the James ...
Radio source-component association for the LOFAR Two-metre Sky Survey with region-based convolutional neural networks
(2022-12-01)
Radio loud active galactic nuclei (RLAGNs) are often morphologically complex objects that can consist of multiple, spatially separated, components. Astronomers often rely on visual inspection to resolve radio component ...
The survey of planetary nebulae in Andromeda (M31). IV. Radial oxygen and argon abundance gradients of the thin and thicker disc
(2022-12-01)
We obtain a magnitude-limited sample of Andromeda (M 31) disc PNe with chemical abundance estimated through the direct detection of the [O III] 4363 Å line. This leads to 205 and 200 PNe with oxygen and argon abundances, ...