Search Publications
Observational constraints on the deceleration parameter in a tilted universe
Asvesta, Kerkyra; Kazantzidis, Lavrentios; Perivolaropoulos, Leandros +1 more
We study a parametrization of the deceleration parameter in a tilted universe, namely a cosmological model equipped with two families of observers. The first family follows the smooth Hubble flow, while the second is the real observers residing in a typical galaxy inside a bulk flow and moving relative to the smooth Hubble expansion with finite pe…
Constraining the original composition of the gas forming first-generation stars in globular clusters
Milone, A. P.; Cordoni, G.; Marino, A. F. +13 more
Disentangling distinct stellar populations along the red-giant branches (RGBs) of globular clusters (GCs) is possible by using the pseudo-two-colour diagram dubbed chromosome map (ChM). One of the most intriguing findings is that the so-called first-generation (1G) stars, characterized by the same chemical composition of their natal cloud, exhibit…
The GALAH survey: chemical clocks
Lewis, Geraint F.; Casey, Andrew R.; Buder, Sven +29 more
We present the first large-scale study that demonstrates how ages can be determined for large samples of stars through Galactic chemical evolution. Previous studies found that the elemental abundances of a star correlate directly with its age and metallicity. Using this knowledge, we derive ages for 214 577 stars in GALAH DR3 using only overall me…
Cosmic evolution of low-excitation radio galaxies in the LOFAR two-metre sky survey deep fields
Calistro Rivera, Gabriela; Małek, Katarzyna; Wang, Lingyu +16 more
Feedback from low-excitation radio galaxies (LERGs) plays a key role in the lifecycle of massive galaxies in the local Universe; their evolution, and the impact of these active galactic nuclei on early galaxy evolution, however, remain poorly understood. We use a sample of 10 481 LERGs from the first data release of the LOFAR two-metre Sky Survey …
The Pristine survey - XVI. The metallicity of 26 stellar streams around the Milky Way detected with the STREAMFINDER in Gaia EDR3
Sestito, Federico; McConnachie, Alan W.; Malhan, Khyati +21 more
We use the photometric metallicities provided by the panoramic Pristine survey to study the veracity and derive the metallicities of the numerous stellar streams found by the application of the STREAMFINDER algorithm to the Gaia Early Data Release 3 data. All 26 streams present in Pristine show a clear metallicity distribution function, which prov…
First discoveries and localizations of Fast Radio Bursts with MeerTRAP: real-time, commensal MeerKAT survey
Prochaska, J. Xavier; Kramer, M.; Tejos, N. +24 more
We report on the discovery and localization of fast radio bursts (FRBs) from the MeerTRAP project, a commensal fast radio transient-detection programme at MeerKAT in South Africa. Our hybrid approach combines a coherent search with an average field-of-view (FoV) of 0.4 $\rm deg^{2}$ with an incoherent search utilizing a FoV of ~1.27 $\rm deg^{2}$ …
Comprehensive catalogue of the overall best distances and properties of 402 galactic novae
Schaefer, Bradley E.
I derive the overall best distances for all 402 known Galactic novae, and I collect their many properties. The centrepiece is the 74 novae with accurate parallaxes from the new Gaia data release. For the needed priors, I have collected 171 distances based on old methods (including expansion parallaxes and extinction distances). Further, I have col…
WISDOM Project - X. The morphology of the molecular ISM in galaxy centres and its dependence on galaxy structure
Kruijssen, J. M. Diederik; Schruba, Andreas; Williams, Thomas G. +12 more
We use high-resolution maps of the molecular interstellar medium (ISM) in the centres of 86 nearby galaxies from the millimetre-Wave Interferometric Survey of Dark Object Masses (WISDOM) and Physics at High Angular Resolution in Nearby GalaxieS (PHANGS) surveys to investigate the physical mechanisms setting the morphology of the ISM at molecular c…
Polycyclic aromatic hydrocarbons in Seyfert and star-forming galaxies
Rigopoulou, D.; Pereira-Santaella, M.; Alonso-Herrero, A. +3 more
Polycyclic Aromatic Hydrocarbons (PAHs) are carbon-based molecules resulting from the union of aromatic rings and related species, which are likely responsible for strong infrared emission features. In this work, using a sample of 50 Seyfert galaxies (DL < 100 Mpc) we compare the circumnuclear (inner kpc) PAH emission of AGN to that …
Mysterious odd radio circle near the large magellanic cloud - an intergalactic supernova remnant?
Haberl, F.; Umana, G.; Hill, T. +48 more
We report the discovery of J0624-6948, a low-surface brightness radio ring, lying between the Galactic Plane and the large magellanic cloud (LMC). It was first detected at 888 MHz with the Australian Square Kilometre Array Pathfinder (ASKAP), and with a diameter of ~196 arcsec. This source has phenomenological similarities to odd radio circles (OR…