Search Publications
The frequency of extreme X-ray variability for radio-quiet quasars
Brandt, W. N.; Liu, H.; Luo, B. +3 more
We analyse 1598 serendipitous Chandra X-ray observations of 462 radio-quiet quasars to constrain the frequency of extreme amplitude X-ray variability that is intrinsic to the quasar corona and innermost accretion flow. The quasars in this investigation are all spectroscopically confirmed, optically bright (mi ≤ 20.2), and contain no ide…
Implications of dark matter cascade decay from DAMPE, HESS, Fermi-LAT, and AMS02 data
Gao, Yu; Ma, Yin-Zhe
Recent high-energy cosmic e± measurement from the DArk Matter Particle Explorer (DAMPE) satellite confirms the deviation of total cosmic ray electron spectrum above 700-900 GeV from a simple power law. In this paper, we demonstrate that the cascade decay of dark matter (DM) can account for DAMPE's TeV e+e- spectrum…
A panchromatic spatially resolved analysis of nearby galaxies - I. Sub-kpc-scale main sequence in grand-design spirals
Popesso, P.; Rodighiero, G.; Bianchi, S. +9 more
We analyse the spatially resolved relation between stellar mass (M⋆) and star formation rate (SFR) in disc galaxies (i.e. the main sequence, MS). The studied sample includes eight nearby face-on grand-design spirals, e.g. the descendant of high-redshift, rotationally supported star-forming galaxies. We exploit photometric information ov…
A PSF-based Approach to TESS High quality data Of Stellar clusters (PATHOS) - III. Exploring the properties of young associations through their variables, dippers, and candidate exoplanets
Nardiello, D.
Young associations in star-forming regions are stellar systems that allow us to understand the mechanisms that characterize the stars in their early life and what happens around them. In particular, the analysis of the discs and of the exoplanets around young stars allows us to know the key processes that prevail in their evolution and understand …
Radio morphology-accretion mode link in Fanaroff-Riley type II low-excitation radio galaxies
Vignali, C.; Grandi, P.; Boccardi, B. +2 more
Fanaroff-Riley type II (FR II) low-excitation radio galaxies (LERGs) are characterized by weak nuclear excitation on parsec-scales and properties typical of powerful FR IIs (defined as high-excitation radio galaxies, hereafter HERGs/BLRGs) on kiloparsec-scales. Since a link between the accretion properties and the power of the produced jets is exp…
RELICS: spectroscopy of gravitationally lensed z ≃ 2 reionization-era analogues and implications for C III] detections at z > 6
Charlot, Stéphane; Chevallard, Jacopo; Mahler, Guillaume +17 more
Recent observations have revealed the presence of strong C III] emission (EW $_{\rm {C\,{\small III}]}}\gt 20$ Å) in z > 6 galaxies, the origin of which remains unclear. In an effort to understand the nature of these line emitters, we have initiated a survey targeting C III] emission in gravitationally lensed reionization-era analogues identifi…
Investigating the spectral age problem with powerful radio galaxies
Croston, Judith H.; Hardcastle, Martin J.; Mahatma, Vijay H. +3 more
The 'spectral age problem' is our systematic inability to reconcile the maximum cooling time of radiating electrons in the lobes of a radio galaxy with its age as modelled by the dynamical evolution of the lobes. While there are known uncertainties in the models that produce both age estimates, 'spectral' ages are commonly underestimated relative …
Multiphase outflows in post-starburst E+A galaxies - II. A direct connection between the neutral and ionized outflow phases
Netzer, Hagai; Xavier Prochaska, J.; Baron, Dalya +1 more
Post-starburst E+A galaxies are systems that hosted a powerful starburst that was quenched abruptly. Simulations suggest that these systems provide the missing link between major merger ULIRGs and red and dead ellipticals, where AGN feedback is responsible for the expulsion or destruction of the molecular gas. However, many details remain unresolv…
Binary-induced spiral arms inside the disc cavity of AB Aurigae
Pinte, Christophe; Ribas, Álvaro; Macías, Enrique +5 more
In this work we demonstrate that the inner spiral structure observed in AB Aurigae can be created by a binary star orbiting inside the dust cavity. We find that a companion with a mass-ratio of 0.25, semimajor axis of 40 au, eccentricity of 0.5, and inclination of 90° produces gaseous spirals closely matching the ones observed in 12CO (…
Hard X-ray selected giant radio galaxies - II. Morphological evidence of restarted radio activity
Venturi, T.; Dallacasa, D.; Ubertini, P. +10 more
About 6 per cent of radio galaxies (RGs) can reach linear sizes larger than 0.7 Mpc, and are then classified as giant radio galaxies (GRGs). The conditions that make possible the formation of such big structures are still not clear - either core accretion properties or environmental factors. Recent studies have shown that GRGs can be up to four ti…