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Jan 17, 2025 | 
academic.oup.com | Madingley Road |Astronomisches Rechen-Institut
Carbon-rich (C-rich) stars can be found at all metallicities and evolutionary stages. They are often the result of mass-transfer from a companion, but some of the most metal-poor C-rich objects are likely carrying the imprint of the metal-free First Stars from birth. In this work, we employ a neural network to predict metallicities and carbon abundances for over 10 million stars with Gaia low-resolution XP spectra, down to and up to .
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Jan 6, 2025 | 
academic.oup.com | Madingley Road
We study star formation variability, or burstiness, as a method to constrain and compare different galaxy formation models at high redshift using the Azahar simulation suite. The models range from magneto-hydrodynamics with turbulence-driven star formation to more sophisticated setups incorporating radiative transfer and cosmic ray physics.
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Jan 6, 2025 | 
academic.oup.com | Madingley Road |David E
Ideal candidates for ultralight bosonic dark matter (DM) – also called fuzzy dark matter (FDM) – from particle physics are ultralight axions that can emerge from both field theory and string theory.
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Jan 6, 2025 | 
academic.oup.com | Madingley Road |Aix Marseille Université |Gower Street
The advent of the JWST has facilitated the robust detection of extremely high-redshift galaxies out to (e.g. Arrabal Haro et al. 2023; Curtis-Lake et al. 2023; Finkelstein et al. 2024; Carniani et al. 2024; Castellano et al. 2024; D’Eugenio et al. 2024). The detection of these galaxies pushes back the onset of Cosmic Dawn to at least . The identification of galaxies at such redshifts was previously predicted by various studies (Hashimoto et al. 2018; Roberts-Borsani et al. 2020; Laporte et al.
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Dec 5, 2024 | 
academic.oup.com | Madingley Road |Wilberforce Road
Globular clusters (GCs) are sites of extremely efficient star formation, and recent studies suggest they significantly contributed to the early Milky Way’s stellar mass build-up. Although their role has since diminished, GCs’ impact on the Galaxy’s initial evolution can be traced today by identifying their most chemically unique stars—those with anomalous nitrogen and aluminum overabundances and oxygen depletion.
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Dec 5, 2024 | academic.oup.com | Madingley Road |Wilberforce Road
Globular clusters (GCs) are sites of extremely efficient star formation, and recent studies suggest they significantly contributed to the early Milky Way’s stellar mass build-up. Although their role has since diminished, GCs’ impact on the Galaxy’s initial evolution can be traced today by identifying their most chemically unique stars—those with anomalous nitrogen and aluminum overabundances and oxygen depletion.
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Nov 30, 2024 | 
academic.oup.com | Denys Wilkinson Building |Keble Road |Madingley Road
Lyα is the transition to the ground state from the first excited state of hydrogen (the most common element). Resonant scattering of this line by neutral hydrogen greatly impedes its emergence from galaxies, so the fraction of galaxies emitting Lyα is a tracer of the neutral fraction of the intergalactic medium (IGM), and thus the history of reionisation.
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Nov 21, 2024 | 
aanda.org | Marija Jankovic |Mark Wyatt |Madingley Road |Friedrich-Schiller-Universität Jena
Our model reproduces the basic theoretical expectations regarding the collisional damping of indestructible particles in discs. In discs in which particle mass can be changed by cratering and catastrophic disruption, the critical projectile-to-target mass ratio determines how efficient collisional damping is.
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Nov 12, 2024 | 
academic.oup.com | Madingley Road |Gower Street |de Graaff
We present NIRSpec/MSA observations from the JWST large-area survey WIDE, targeting the rest-frame UV–optical spectrum of Ulema, a radio-AGN host at redshift z = 4.6348. The low-resolution prism spectrum displays high equivalent width nebular emission, with remarkably high ratios of low-ionisation species of oxygen, nitrogen and sulphur, relative to hydrogen; auroral O+ emission is clearly detected, possibly also C+.
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Nov 12, 2024 | 
academic.oup.com | Space science |Abu Dhabi |Madingley Road
The Small Magellanic Cloud (SMC) is a dwarf irregular, star-forming, low-metallicity galaxy with total stellar mass of (Bekki & Stanimirović 2009). The SMC is interacting with the large magellanic cloud and the Milky Way, and is a highly disrupted system (Murai & Fujimoto 1980). As the SMC is so close, we can study these effects in detail, something that is not possible for more distant galaxies of similar size.
