Search Publications
Melnick 33Na: a very massive colliding-wind binary system in 30 Doradus
Townsley, Leisa K.; Broos, Patrick S.; Crowther, Paul A. +2 more
We present spectroscopic analysis of the luminous X-ray source Melnick 33Na (Mk 33Na, HSH95 16) in the Large Magellanic Cloud (LMC) 30 Doradus region (Tarantula Nebula), utilizing new time-series Very Large Telescope/Ultraviolet and Visual Echelle Spectrograph spectroscopy. We confirm Mk 33Na as a double-lined O-type spectroscopic binary with a ma…
Cometary dust analogues for physics experiments
Zhang, X.; Sierks, H.; Blum, J. +25 more
The CoPhyLab (Cometary Physics Laboratory) project is designed to study the physics of comets through a series of earth-based experiments. For these experiments, a dust analogue was created with physical properties comparable to those of the non-volatile dust found on comets. This 'CoPhyLab dust' is planned to be mixed with water and CO2
The TESS Triple-9 Catalog: 999 uniformly vetted exoplanet candidates
Kostov, Veselin B.; Colón, Knicole D.; Christiansen, Jessie L. +20 more
The Transiting Exoplanet Survey Satellite (TESS) has detected thousands of exoplanet candidates since 2018, most of which have yet to be confirmed. A key step in the confirmation process of these candidates is ruling out false positives through vetting. Vetting also eases the burden on follow-up observations, provides input for demographics studie…
Fundamental effective temperature measurements for eclipsing binary stars - III. SPIRou near-infrared spectroscopy and CHEOPS photometry of the benchmark G0V star EBLM J0113+31
Alonso, R.; Deleuil, M.; Erikson, A. +74 more
EBLM J0113+31 is a moderately bright (V = 10.1), metal-poor ([Fe/H] ≈-0.3) G0V star with a much fainter M dwarf companion on a wide, eccentric orbit (= 14.3 d). We have used near-infrared spectroscopy obtained with the SPIRou spectrograph to measure the semi-amplitude of the M dwarf's spectroscopic orbit, and high-precision photometry of the eclip…
Stellar kinematics of dwarf galaxies from multi-epoch spectroscopy: application to Triangulum II
Caldwell, Nelson; Martin, Nicolas F.; Mateo, Mario +9 more
We present new MMT/Hectochelle spectroscopic measurements for 257 stars observed along the line of sight to the ultrafaint dwarf galaxy Triangulum II (Tri II). Combining results from previous Keck/DEIMOS spectroscopy, we obtain a sample that includes 16 likely members of Tri II, with up to 10 independent redshift measurements per star. To this mul…
Can we reveal the core-chemical composition of ultra-massive white dwarfs through their magnetic fields?
Córsico, Alejandro H.; Rebassa-Mansergas, Alberto; Althaus, Leandro G. +5 more
Ultra-massive white dwarfs ($1.05\, \rm M_\odot \lesssim M_{WD}$) are particularly interesting objects that allow us to study extreme astrophysical phenomena such as type Ia supernovae explosions and merger events. Traditionally, ultra-massive white dwarfs are thought to harbour oxygen-neon (ONe) cores. However, recent theoretical studies and new …
The peculiar chemical abundance of the transitional millisecond pulsar PSR J1023+0038 - Li enhancement
Breton, R. P.; Kennedy, M. R.; Mata Sánchez, D. +3 more
Using high-resolution optical spectroscopy we determine the chemical abundance of the secondary star in the binary millisecond pulsar PSR J1023+0038. We measure a metallicity of [Fe/H] = 0.48 ± 0.04 which is higher than the Solar value and in general find that the element abundances are different compared to the secondary stars in X-ray binaries a…
The search for gas in debris discs: ALMA detection of CO gas in HD 36546
Henning, Thomas; Villaver, Eva; Rivière-Marichalar, Pablo +9 more
Debris discs represent the last stages of planet formation and as such are expected to be depleted of primordial gas. None the less, in the last few years the presence of cold gas has been reported in ~20 debris discs from far-infrared to (sub-)mm observations and hot gas has been observed in the optical spectra of debris discs for decades. While …
A census of post-AGB stars in Gaia DR3: evidence for a substantial population of Galactic post-RGB stars
Oudmaijer, René D.; Jones, Emma R. M.; Vioque, Miguel
This paper presents the first census of Galactic post-asymptotic giant branch (post-AGB) stars in the Hertzsprung-Russell (HR) diagram. We combined Gaia DR3 parallax-based distances with extinction corrected integrated fluxes and derived luminosities for a sample of 185 stars that had been proposed to be post-AGB stars in the literature. The lumin…
Asteroid phase curves using sparse Gaia DR2 data and differential dense light curves
Shevchenko, V.; Kwiatkowski, T.; Oszkiewicz, D. +10 more
The amount of sparse asteroid photometry being gathered by both space- and ground-based surveys is growing exponentially. This large volume of data poses a computational challenge owing to both the large amount of information to be processed and the new methods needed to combine data from different sources (e.g. obtained by different techniques, i…