Search Publications
METAL-Z: Measuring Dust Depletion in Low-metallicity Dwarf Galaxies
Jenkins, Edward B.; Gordon, Karl D.; Rafelski, Marc +6 more
The cycling of metals between interstellar gas and dust is a critical aspect of the baryon cycle of galaxies, yet our understanding of this process is limited. This study focuses on understanding dust depletion effects in the low-metallicity regime (<20% Z ⊙) typical of cosmic noon. Using medium-resolution UV spectroscopy from the Co…
The relation between magnetic field inclination and the apparent motion of penumbral grains
Sobotka, Michal; Jurčák, Jan; Castellanos Durán, Juan Sebastián +1 more
Context. The bright heads of penumbral filaments, penumbral grains (PGs), show apparent horizontal motions inward, toward the umbra, or outward, away from the umbra.
Aims: We aim to ascertain statistically whether the direction of PGs' apparent motion is related to the inclination of the surrounding magnetic field.
Methods: We used spect…
Stellar rotations and the disentanglement of the Galactic thin and thick discs
da Silva, M. P.; Alves-Brito, A.; do Nascimento, J. D.
The kinematics, mean α-elements, and ages of the stars reveal two distinct disc populations observed in the Solar neighbourhood. Although several studies have been carried out to characterize abundances of chemical elements and kinematic identifications in these populations, there are few studies that dealt with the analysis of stellar rotation an…
The enigma of Gaia18cjb: A possible rare hybrid of FUor and EXor properties
Pál, András; Ogłoza, Waldemar; Ábrahám, Péter +28 more
Context. Gaia18cjb is one of the Gaia-alerted eruptive young star candidates that has been experiencing a slow and strong brightening during the last 13 years, similarly to some FU Orionis-type objects.
Aims: The aim of this work is to derive the young stellar nature of Gaia18cjb and determine its physical and accretion properties to classify…
Noble Gas Planetology and the Xenon Clouds of Uranus
Zahnle, Kevin
Noble gases provide tracers of cosmic provenance that are accessible to a future Uranus atmospheric probe. Argon and krypton are expected to be well mixed on Uranus with respect to H2 and He, although condensation at the winter pole may be possible. The Ar/H2 and Ar/Kr ratios address whether the materials accreted by Uranus r…
Close Major-merger Pairs at z = 0: Star-forming Galaxies with Pseudobulges
Wang, Wei; Xu, Cong; Fang, Taotao +5 more
We present a study of star-forming galaxies (SFGs) with pseudobulges (bulges with Sérsic index n < 2) in a local close major-merger galaxy pair sample (H-KPAIR). With data from new aperture photometries in the optical and near-infrared bands (aperture size of 7 kpc) and from the literature, we find that the mean Age of central stellar populatio…
New candidate hypervelocity red clump stars in the inner Galactic bulge
Minniti, D.; Rejkuba, M.; Luna, A. +5 more
We search for high-velocity stars in the inner region of the Galactic bulge using a selected sample of red clump stars. Some of those stars might be considered hypervelocity stars (HVSs). Even though the HVSs ejection relies on an interaction with the supermassive black hole (SMBH) at the centre of the Galaxy, there are no confirmed detections of …
TOI-1135 b: A young hot Saturn-size planet orbiting a solar-type star
Nagel, E.; Béjar, V. J. S.; Zapatero Osorio, M. R. +20 more
Despite the thousands of planets in orbit around stars known to date, the mechanisms of planetary formation, migration, and atmospheric loss remain unresolved. In this work, we confirm the planetary nature of a young Saturn-size planet transiting a solar-type star every 8.03 d, TOI-1135 b. The age of the parent star is estimated to be in the inter…
Broadband X-ray spectral and timing properties of the accreting millisecond X-ray pulsar IGR J17498‑2921 during the 2023 outburst
Huang, Y.; Zhang, S.; Zhang, S. N. +10 more
We report on the broadband spectral and timing properties of the accreting millisecond X-ray pulsar IGR J17498‑2921 during its April 2023 outburst. We used data from NICER (1–10 keV), NuSTAR (3–79 keV), Insight-HXMT (2–150 keV), and INTEGRAL (30–150 keV). We detected significant 401 Hz pulsations across the 0.5–150 keV band. The pulse fraction inc…
Candidate Main-belt Asteroids for Surface Heterogeneity
Hasegawa, Sunao; Marsset, Michaël; Bus, Schelte J. +10 more
Large terrestrial bodies in our solar system like the Earth, Mars, Mercury, and the Moon exhibit geologically complex surfaces with compositional heterogeneity. From past studies using large telescopes and spacecraft, it was shown that asteroids with diameters larger than 100 km also show surface heterogeneity at hemispheric scales, while on small…