Search Publications
The first seven months of the 2020 X-ray outburst of the magnetar SGR J1935+2154
Tiengo, A.; Mereghetti, S.; Rea, N. +10 more
The magnetar SGR J1935+2154 underwent a new active episode on 2020 April 27-28, when a forest of hundreds of X-ray bursts and a large enhancement of the persistent flux were detected. For the first time, a radio burst with properties similar to those of fast radio bursts and with a X-ray counterpart was observed from this source, showing that magn…
Ejection-accretion connection in NLS1 AGN 1H 1934-063
Cusumano, G.; Fabian, A. C.; Pinto, C. +7 more
Accretion and ejection of matter in active galactic nuclei (AGNs) are tightly connected phenomena and represent fundamental mechanisms regulating the growth of the central supermassive black hole and the evolution of the host galaxy. However, the exact physical processes involved are not yet fully understood. We present a high-resolution spectral …
Relic galaxy analogues in TNG50 simulation: the formation pathways of surviving red nuggets in a cosmological simulation
Chies-Santos, Ana L.; Ferreira, Leonardo; De Rossi, María Emilia +4 more
Relic galaxies are massive compact quiescent galaxies that formed at high-redshift and remained almost unchanged since then. In this work, we search for analogues to relic galaxies in the TNG50 cosmological simulations to understand relic formation and test the ability of TNG50 to reproduce such rare objects. Using stellar mass, age, radius, quies…
Tidally stripped halo stars from the Large Magellanic Cloud in the Galactic North
Peñarrubia, Jorge; Petersen, Michael S.; Jones, Ella
We examine whether the Large Magellanic Cloud (LMC) is currently losing its stellar halo to Milky Way (MW) tides. We present a live N-body model for the ongoing MW-LMC interaction that predicts a prominent stream of stars tidally stripped from the progenitor LMC. We use this model to define a strategy to search for stripped material in kinematic s…
Modelling the stellar halo with RR-Lyrae stars
Li, Chengdong; Binney, James
A seven-parameter distribution function (DF) is fitted to $20\, 000$ RR-Lyrae stars for which only astrometric data are available. The observational data are predicted by the DF in conjunction with the gravitational potential of a self-consistent model Galaxy defined by DFs for the dark halo, the bulge, and a four-component disc. Tests of the tech…
Atmospheric mass-loss and stellar wind effects in young and old systems - I. Comparative 3D study of TOI-942 and TOI-421 systems
Carleo, Ilaria; Vidotto, Aline A.; Kubyshkina, Daria +3 more
At young ages, when radiation from the host star is high, and the planet is hot and inflated after formation, planetary atmospheric mass-loss can be extremely strong compared to older planets. In turn, stellar winds are faster and denser for young stars compared to evolved main-sequence stars. Their interaction with escaping planetary atmospheres …
The photo-astrometric vertical tracer density of the Milky Way - II. Results from Gaia
Everall, Andrew; Boubert, Douglas; Grand, Robert J. J. +2 more
We use Gaia photometry and astrometry to estimate the vertical spatial structure of the Milky Way at the Solar radius, formally accounting for sample incompleteness (the selection function) and parallax measurement uncertainty. Our results show impressive precision demonstrating the power of the Gaia data. However, systematic errors dominate the p…
Two decades of X-ray observations of the isolated neutron star RX J1856.5 - 3754: detection of thermal and non-thermal hard X-rays and refined spin-down measurement
Mereghetti, Sandro; Turolla, Roberto; Tiengo, Andrea +6 more
The soft X-ray pulsar RX J1856.5 - 3754 is the brightest member of a small class of thermally emitting, radio-silent, isolated neutron stars. Its X-ray spectrum is almost indistinguishable from a blackbody with $kT^\infty \approx {60}\, {\rm eV}$, but evidence of harder emission above $\sim {1}\, {\rm keV}$ has been recently found. We report on a …
MUSE-ALMA haloes VII: survey science goals & design, data processing and final catalogues
Hayes, M.; Kacprzak, G. G.; Kuntschner, H. +16 more
The gas cycling in the circumgalactic regions of galaxies is known to be multi-phase. The MUSE-ALMA Haloes survey gathers a large multi-wavelength observational sample of absorption and emission data with the goal to significantly advance our understanding of the physical properties of such CGM gas. A key component of the MUSE-ALMA Haloes survey i…
Galaxy source counts at 7.7, 10, and 15 µm with the James Webb Space Telescope
Kilerci, Ece; Hashimoto, Tetsuya; Goto, Tomotsugu +7 more
We present mid-infrared (IR) galaxy number counts based on the Early Release Observations obtained by the James Webb Space Telescope (JWST) at 7.7-, 10-, and 15-µm (F770W, F1000W, and F1500W, respectively) bands of the Mid-Infrared Instrument (MIRI). Due to the superior sensitivity of JWST, the 80-per cent completeness limits reach 0.32, 0.7…