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A Benchmark White Dwarf-Ultracool Dwarf Wide Field Binary
(2023-12-19)
We present the discovery and multi-wavelength characterisation of VVV J1438-6158 AB, a new field wide-binary system consisting of a 4.6(+5.5-2.4) Gyr and Teff = 9500+/-125 K DA white dwarf (WD) and a Teff = 2400+/-50 K M8 ...
Gaia21bty: An EXor light curve exhibiting a FUor spectrum
(2023-10-30)
Gaia21bty, a pre-main sequence star that previously had shown aperiodic dips in its light curve, underwent a considerable Delta G~2.9 mag brightening that occurred over a few months between 2020 October - 2021 February. ...
Plausible association of distant late M dwarfs with low-frequency radio emission
(2023-10-17)
We present the serendipitous discovery of eight distant (> 50 pc) late M dwarfs with plausible associated radio emission at 144 MHz. The M-dwarf nature of our sources has been confirmed with optical spectroscopy performed ...
The puzzle of the formation of T8 dwarf Ross 458c
(2023-06-01)
At the lowest masses, the distinction between brown dwarfs and giant exoplanets is often blurred and literature classifications rarely reflect the deuterium burning boundary. Atmospheric characterization may reveal the ...
Identifying and characterizing ultracool dwarfs ejected from post-encounter disintegrating systems
(2023-06-01)
Disintegrating multiple systems have been previously discovered from kinematic studies of the $\it Hipparcos$ catalogue. They are presumably the result of dynamical encounters taking place in the Galactic disk between ...
A blue depression in the optical spectra of M dwarfs
(2023-05-12)
A blue depression is found in the spectra of M dwarfs from 4000 to 4500A. This depression shows an increase toward lower temperatures though is particularly sensitive to gravity and metallicity. It is the single most ...
The Andromeda Galaxy’s Last Major Merger: Constraints from the survey of Planetary Nebulae
(The International Astronomical Union, 2023-05-04)
The Andromeda galaxy (M 31) has experienced a tumultuous merger history as evidenced by the many substructures present in its inner halo. We use planetary nebulae (PNe) as chemodynamic tracers to shed light on the recent ...
A systematic survey of millimetre-wavelength flaring variability of Young Stellar Objects in the Orion Nebula Cluster
(2023-03-29)
High-energy processes are ubiquitous even in the earliest stages of protostellar evolution. Motivated by the results of our systematic search for intense centimeter radio flares in Young Stellar Objects (YSOs) and by rare ...
The wide-field, multiplexed, spectroscopic facility WEAVE: Survey design, overview, and simulated implementation
(2023-03-11)
WEAVE, the new wide-field, massively multiplexed spectroscopic survey facility for the William Herschel Telescope, will see first light in late 2022. WEAVE comprises a new 2-degree field-of-view prime-focus corrector system, ...
Chemo-Dynamical Evolution of Galaxies
(Springer Nature, 2023-02-17)
Stars are fossils that retain the history of their host galaxies. Elements heavier than helium are created inside stars and are ejected when they die. From the spatial distribution of elements in galaxies, it is therefore ...