Search Publications
The ultraviolet habitable zone of exoplanets
Ghirlanda, G.; Ghisellini, G.; Borsa, F. +2 more
The dozens of rocky exoplanets discovered in the circumstellar habitable zone (CHZ) currently represent the most suitable places to host life as we know it outside the Solar system. However, the presumed presence of liquid water on the CHZ planets does not guarantee suitable environments for the emergence of life. According to experimental studies…
SN 2022acko: The First Early Far-ultraviolet Spectra of a Type IIP Supernova
Van Dyk, Schuyler D.; Smith, Nathan; Hillier, D. John +41 more
We present five far- and near-ultraviolet spectra of the Type II plateau supernova, SN 2022acko, obtained 5, 6, 7, 19, and 21 days after explosion, all observed with the Hubble Space Telescope/Space Telescope Imaging Spectrograph. The first three epochs are earlier than any Type II plateau supernova has been observed in the far-ultraviolet reveali…
The multiwavelength view of shocks in the fastest nova V1674 Her
Mukai, K.; Sokoloski, J. L.; Buson, S. +41 more
Classical novae are shock-powered multiwavelength transients triggered by a thermonuclear runaway on an accreting white dwarf. V1674 Her is the fastest nova ever recorded (time to declined by two magnitudes is t2 = 1.1 d) that challenges our understanding of shock formation in novae. We investigate the physical mechanisms behind nova em…
A Bayesian approach for torque modelling of BeXRB pulsars with application to super-Eddington accretors
Vasilopoulos, G.; Wilson-Hodge, C. A.; Malacaria, C. +3 more
In this study, we present a method to estimate posterior distributions for standard accretion torque model parameters and binary orbital parameters for X-ray binaries using a nested sampling algorithm for Bayesian parameter estimation. We study the spin evolution of two Be X-ray binary systems in the Magellanic Clouds, RX J0520.5-6932 and RX J0209…
The Araucaria project: High-precision orbital parallaxes and masses of binary stars. I. VLTI/GRAVITY observations of ten double-lined spectroscopic binaries
Kervella, P.; Mérand, A.; Gallenne, A. +4 more
Aims: We aim to measure very precise and accurate model-independent masses and distances of detached binary stars. Precise masses at the < 1% level are necessary to test and calibrate stellar interior and evolution models, while precise and independent orbital parallaxes are essential to check for the next Gaia data releases.
Methods:…
The Gaia-ESO Survey: Chemical evolution of Mg and Al in the Milky Way with machine learning
Gilmore, G.; Bayo, A.; Guiglion, G. +15 more
Context. To take full advantage of upcoming large-scale spectroscopic surveys, it will be necessary to parameterize millions of stellar spectra in an efficient way. Machine learning methods, especially convolutional neural networks (CNNs), will be among the main tools geared at achieving this task.
Aims: We aim to prepare the groundwork for m…
High Energy Solar Particle Events and Their Relationship to Associated Flare, CME and GLE Parameters
Vainio, R.; Dalla, S.; Raukunen, O. +3 more
Large solar eruptive events, including solar flares and coronal mass ejections (CMEs), can lead to solar energetic particle (SEP) events. During these events, protons are accelerated up to several GeV and pose numerous space weather risks. These risks include, but are not limited to, radiation hazards to astronauts and disruption to satellites and…
Extending the extinction law in 30 Doradus to the infrared with JWST
Fahrion, Katja; De Marchi, Guido
We measured the extinction law in the 30 Dor star formation region in the Large Magellanic Cloud using Early Release Observations (EROs) taken with Near-Infrared Camera (NIRCam) on board the JWST, thereby extending previous studies carried out with the Hubble Space Telescope to the infrared. We used red clump stars to derive the direction of the r…
The Celestial Reference Frame at K Band: Imaging. I. The First 28 Epochs
de Witt, Aletha; Jacobs, Christopher S.; Gordon, David +3 more
We present K-band (24 GHz) images of 731 compact extragalactic radio sources with submilliarcsecond resolution, based on radio interferometric observations made with the Very Long Baseline Array of 10 telescopes during 29 day long sessions spanning from 2015 to 2018 and recorded at 2048 Mbps. Many of these sources are imaged with submilliarcsecond…
2D chemical evolution models. II. Effects of multiple spiral arm patterns on O, Eu, Fe, and Ba abundance gradients
Recio-Blanco, A.; Palicio, P. A.; Poggio, E. +7 more
Context. According to observations and numerical simulations, the Milky Way could exhibit several spiral-arm modes of various pattern speeds, with the slower patterns located at larger galactocentric distances.
Aims: Our aim is to quantify the effects of the spiral arms on the azimuthal variations in the chemical abundances of oxygen and iron…