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A blue depression in the optical spectra of M dwarfs
(2023-07-01)
A blue depression is found in the spectra of M dwarfs from 4000 to 4500 Å. This depression shows an increase towards lower temperatures, though it is particularly sensitive to gravity and metallicity. It is the single ...
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 ...
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 ...
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 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 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, ...