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Related publications (50)
Small-amplitude Red Giants Elucidate the Nature of the Tip of the Red Giant Branch as a Standard Candle
Richard Irving Anderson, Nolan Wayne Koblischke
The tip of the red giant branch (TRGB) is an important standard candle for determining luminosity distances. Although several 105 small-amplitude red giant stars (SARGs) have been discovered, variability was previously considered irrelevant for the TRGB as ...
Bristol2024Standardized Luminosity of the Tip of the Red Giant Branch Utilizing Multiple Fields in NGC 4258 and the CATs Algorithm
The tip of the red giant branch provides a luminous standard candle for calibrating distance ladders that reach Type Ia supernova (SN Ia) hosts. However, recent work reveals that tip measurements vary at the similar to 0.1 mag level for different stellar p ...
Bristol2023The extended stellar halo' of the Ursa Minor dwarf galaxy
Stellar candidates in the Ursa Minor (UMi) dwarf galaxy have been found using a new Bayesian algorithm applied to Gaia EDR3 data. Five of these targets are located in the extreme outskirts of UMi, from similar to 5 to 12 elliptical half-light radii (r h), ...
OXFORD UNIV PRESS2023Detailed asteroseismic modelling of RR Lyrae stars with non-radial modes
Photometric observations from the last decade have revealed additional low-amplitude periodicities in many classical pulsators that are likely due to pulsations in non-radial modes. One group of multimode RR Lyrae stars, the so-called 0.61 stars, is partic ...
Oxford2023Emission-line properties of IllustrisTNG galaxies: from local diagnostic diagrams to high-redshift predictions for JWST
Michaela Hirschmann, Adèle Marie Françoise Plat
We compute synthetic, rest-frame optical and ultraviolet (UV) emission-line properties of galaxy populations at redshifts from z approximate to 0 to =8 in a full cosmological framework. We achieve this by coupling, in post-processing, the cosmological Illu ...
Oxford2023To grow old and peculiar: Survey of anomalous variable stars in M80 with age determinations using K2 and Gaia
The globular cluster Messier 80 was monitored by the Kepler space telescope for 80 days during the K2 mission. Continuous, high-precision photometry of such an old, compact cluster allows us for studies of its variable star population in unprecedented deta ...
Les Ulis Cedex A2023The Pristine survey - XX. GTC follow-up observations of extremely metal-poor stars identified from Pristine and LAMOST
A B S T R A C T Ultra-metal-poor stars ( [Fe / H] < -4 . 0) are very rare, and finding them is a challenging task. Both narrow-band photometry and low-resolution spectroscopy have been useful tools for identifying candidates, and in this work, we combine b ...
OXFORD UNIV PRESS2023Resonance ionization of zirconium
Measuring the isotopic composition of trace Zr in presolar stardust grains allows us to study the environment of slow neutron-capture nucleosynthesis in asymptotic giant branch stars. Here, we present a newly characterized Zr resonance ionization scheme th ...
2022A stellar stream remnant of a globular cluster below the metallicity floor
Pascale Jablonka, Carmela Lardo
Stellar ejecta gradually enrich the gas out of which subsequent stars form, making the least chemically enriched stellar systems direct fossils of structures formed in the early Universe(1). Although a few hundred stars with metal content below 1,000th of ...
NATURE PORTFOLIO2022Exploring the origin of low-metallicity stars in Milky-Way-like galaxies with the NIHAO-UHD simulations
The kinematics of the most metal-poor stars provide a window into the early formation and accretion history of the Milky Way (MW). Here, we use five high-resolution cosmological zoom-in simulations (similar to 5 x 10(6) star particles) of MW-like galaxies ...
OXFORD UNIV PRESS2021