L. Grassitelli
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Microturbulence across the Hertzsprung–Russell Diagram Open
Context . Despite its critical importance for determining stellar properties and evolution, the origin and physical nature of microturbulence remains poorly understood. Most of the existing works are focussed on specific spectral types and…
Connecting stellar and galactic scales: Energetic feedback from stellar wind bubbles to supernova remnants Open
Context. Energy and momentum feedback from stars is a key element in models of galaxy formation and interstellar medium (ISM) dynamics, but resolving the relevant length scales in order to directly include this feedback remains beyond the …
Performance and Scaling of PION for Modelling Colliding-Wind Binary Systems Open
Colliding-wind binaries are star systems with strong wind-wind interaction producing X-ray-, radio- and sometimes gamma-ray-emitting plasma. Computer modelling of these systems including magnetic fields and all relevant radiative processes…
Inverse-Compton cooling of thermal plasma in colliding-wind binaries Open
The inverse-Compton effect (IC) is a widely recognized cooling mechanism for both relativistic and thermal electrons in various astrophysical environments, including the intergalactic medium and X-ray emitting plasmas. Its effect on therma…
View article: X-Shooting ULLYSES: Massive stars at low metallicity
X-Shooting ULLYSES: Massive stars at low metallicity Open
Observations of individual massive stars, super-luminous supernovae, gamma-ray bursts, and gravitational wave events involving spectacular black hole mergers indicate that the low-metallicity Universe is fundamentally different from our ow…
View article: Bringing Stellar Evolution and Feedback Together: Summary of Proposals from the Lorentz Center Workshop
Bringing Stellar Evolution and Feedback Together: Summary of Proposals from the Lorentz Center Workshop Open
Stars strongly impact their environment, and shape structures on all scales throughout the universe, in a process known as “feedback.” Due to the complexity of both stellar evolution and the physics of larger astrophysical structures, ther…
View article: Bringing Stellar Evolution & Feedback Together: Summary of proposals from the Lorentz Center Workshop, 2022
Bringing Stellar Evolution & Feedback Together: Summary of proposals from the Lorentz Center Workshop, 2022 Open
Stars strongly impact their environment, and shape structures on all scales throughout the universe, in a process known as ``feedback''. Due to the complexity of both stellar evolution and the physics of larger astrophysical structures, th…
Inverse Compton cooling of thermal plasma in colliding-wind binaries Open
The inverse-Compton effect (IC) is a widely recognized cooling mechanism for both relativistic and thermal electrons in various astrophysical environments, including the intergalactic medium and X-ray emitting plasmas. Its effect on therma…
Mechanical feedback from stellar winds with an application to galaxy formation at high redshift Open
We compute different sets of stellar evolutionary tracks in order to quantify the energy, mass, and metals yielded by massive main-sequence and post-main-sequence winds. Our aim is to investigate the impact of binary systems and of a metal…
Modeling non-thermal emission from SN 1987A Open
The remnant of SN 1987A is the best-studied object of its kind. The rich data-set of its thermal and non-thermal emission across the electromagnetic spectrum poses a unique testbed for the elaboration of particle-acceleration theory. We us…
Modeling non-thermal emission from SN 1987A Open
The remnant of SN 1987A is the best-studied object of its kind. The rich data-set of its thermal and non-thermal emission across the electromagnetic spectrum poses a unique testbed for the elaboration of particle-acceleration theory. We us…
On the Origin of Stochastic, Low-Frequency Photometric Variability in Massive Stars Open
High-precision photometric observations have revealed ubiquitous stochastic low-frequency photometric variability in early-type stars. It has been suggested that this variability arises due to either subsurface convection or internal gravi…
Supporting information for "On the Origin of Stochastic, Low-Frequency Photometric Variability in Massive Stars" Open
This repository contains the data and the Jupyter notebook necessary to reproduce all the figures in Cantiello, Lecoanet, Jermyn, Grassitelli 2021, ApJ (including some additional plots). The minimal amount of data (history.data files) is i…
Supporting information for "On the Origin of Stochastic, Low-Frequency Photometric Variability in Massive Stars" Open
This repository contains the data and the Jupyter notebook necessary to reproduce all the figures in Cantiello, Lecoanet, Jermyn, Grassitelli 2021, ApJ (including some additional plots). The minimal amount of data (history.data files) is i…
View article: Turbulent Gas in Lensed Planck-selected Starbursts at z ∼ 1–3.5
Turbulent Gas in Lensed Planck-selected Starbursts at z ∼ 1–3.5 Open
Dusty star-forming galaxies at high redshift (1 < z < 3) represent the most intense star-forming regions in the universe. Key aspects to these processes are the gas heating and cooling mechanisms, and although it is well known that these g…
The ‘Red Radio Ring’: ionized and molecular gas in a starburst/active galactic nucleus at z ∼ 2.55 Open
We report the detection of the far-infrared (FIR) fine-structure line of singly ionized nitrogen, [N ii] 205 $\mu$m , within the peak epoch of galaxy assembly, from a strongly lensed galaxy, hereafter ‘The Red Radio Ring’; the RRR, at z = …
View article: Subsonic structure and optically thick winds from Wolf–Rayet stars
Subsonic structure and optically thick winds from Wolf–Rayet stars Open
Mass loss by stellar wind is a key agent in the evolution and spectroscopic appearance of massive main sequence and post-main sequence stars. In Wolf–Rayet stars the winds can be so dense and so optically thick that the photosphere appears…
View article: On the optically thick winds of Wolf-Rayet stars
On the optically thick winds of Wolf-Rayet stars Open
(abridged) The strong winds of Wolf-Rayet (WR) stars are important for the\nmechanical and chemical feedback of the most massive stars and determine\nwhether they end their lives as neutron stars or black holes. In this work we\ninvestigat…
Metallicity dependence of envelope inflation in massive stars Open
Recently it has been found that models of massive stars reach the Eddington limit in their interior, which leads to dilute extended envelopes. We perform a comparative study of the envelope properties of massive stars at different metallic…
Asteroseismic test of rotational mixing in low-mass white dwarfs Open
\n We exploit the recent discovery of pulsations in mixed-atmosphere (He/H), extremely low-mass white dwarf precursors (ELM proto-WDs) to test the proposition that rotational mixing is a fundamental process in the formation and evolution o…
Models of low-mass helium white dwarfs including gravitational settling, thermal and chemical diffusion, and rotational mixing Open
A large number of extremely low-mass helium white dwarfs (ELM WDs) have been discovered in recent years. The majority of them are found in close binary systems suggesting they are formed either through a common-envelope phase or via stable…
The IACOB project Open
\n Contains fulltext :\n 168641.pdf (Author’s version preprint ) (Open Access)\n
The IACOB project: III. New observational clues to understand macroturbulent broadening in massive O- and B-type stars Open
We aim to provide new empirical clues about macroturbulent spectral line broadening in O- and B-type stars to evaluate its physical origin. We use high-resolution spectra of ~430 stars with spectral types in the range O4-B9 (all luminosity…
Near-uniform internal rotation of the main-sequence γ Doradus pulsator KIC 7661054 Open
We used Kepler photometry to determine the internal rotation rate of KIC 7661054, a chemically normal γ Dor star on the main sequence at spectral type F2.5 V. The core rotation period of 27.25 ± 0.06 d is obtained from the rotational split…
Massive O- and B-type stars velocities Open
The main observational sample discussed in this paper comprises high-resolution, single snapshot spectra of 431 O- and B-type Galactic stars.\nThe IACOB database includes spectra from two different instruments: the FIES and HERMES spectrog…