Search Publications
Surface gravities for 15 000 Kepler stars measured from stellar granulation and validated with Gaia DR2 parallaxes
Huber, Daniel; Bedding, Timothy R.; Kjeldsen, Hans +1 more
We have developed a method to estimate surface gravity (log g) from light curves by measuring the granulation background, similar to the `flicker' method by Bastien et al. (2016) but working in the Fourier power spectrum. We calibrated the method using Kepler stars for which asteroseismology has been possible with short-cadence data, demonstrating…
Hard X-ray-selected giant radio galaxies - I. The X-ray properties and radio connection
Bird, A. J.; Fiocchi, M.; Ubertini, P. +6 more
We present the first broad-band X-ray study of the nuclei of 14 hard X-ray-selected giant radio galaxies, based both on the literature and on the analysis of archival X-ray data from NuSTAR, XMM-Newton, Swift, and INTEGRAL. The X-ray properties of the sources are consistent with an accretion-related X-ray emission, likely originating from an X-ray…
ALMA observations of lensed Herschel sources: testing the dark matter halo paradigm
Ivison, R. J.; Clements, D. L.; Cooray, A. +23 more
With the advent of wide-area submillimetre surveys, a large number of high-redshift gravitationally lensed dusty star-forming galaxies have been revealed. Because of the simplicity of the selection criteria for candidate lensed sources in such surveys, identified as those with S500 µm > 100 mJy, uncertainties associated with th…
A new mechanical stellar wind feedback model for the Rosette Nebula
Wright, N. J.; Pittard, J. M.; Wareing, C. J. +1 more
The famous Rosette Nebula has an evacuated central cavity formed from the stellar winds ejected from the 2-6 Myr old codistant and comoving central star cluster NGC 2244. However, with upper age estimates of less than 110 000 yr, the central cavity is too young compared to NGC 2244 and existing models do not reproduce its properties. A new proper …
Exploring the dust content of galactic winds with Herschel - II. Nearby dwarf galaxies
Martin, Crystal L.; Veilleux, Sylvain; Bland-Hawthorn, Joss +7 more
We present the results from an analysis of deep Herschel Space Observatory observations of six nearby dwarf galaxies known to host galactic-scale winds. The superior far-infrared sensitivity and angular resolution of Herschel have allowed detection of cold circumgalactic dust features beyond the stellar components of the host galaxies traced by Sp…
The Herschel-ATLAS: magnifications and physical sizes of 500-µm-selected strongly lensed galaxies
Rodighiero, G.; Franceschini, A.; Cooray, A. +10 more
We perform lens modelling and source reconstruction of Sub-millimetre Array (SMA) data for a sample of 12 strongly lensed galaxies selected at 500µm in the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS). A previous analysis of the same data set used a single Sérsic profile to model the light distribution of each background gala…
A complete disclosure of the hidden type-1 AGN in NGC 1068 thanks to 52 yr of broad-band polarimetric observation
Marin, F.
We create the first broad-band polarization spectrum of an active galactic nucleus (AGN) by compiling the 0.1-100 µm, 4.9, and 15 GHz continuum polarization of NGC 1068 from more than 50 yr of observations. Despite the diversity of instruments and apertures, the observed spectrum of linear continuum polarization has distinctive wavelength-de…
SWIFT J1756.9-2508: spectral and timing properties of its 2018 outburst
Sanna, A.; Ferrigno, C.; Papitto, A. +8 more
We discuss the spectral and timing properties of the accreting millisecond X-ray pulsar SWIFT J1756.9-2508 observed by XMM-Newton, NICER, and NuSTAR during the X-ray outburst occurred in April 2018. The spectral properties of the source are consistent with a hard state dominated at high energies by a non-thermal power-law component with a cut-off …
Calibration of colour gradient bias in shear measurement using HST/CANDELS data
Schrabback, T.; Hoekstra, H.; Maoli, R. +6 more
Accurate shape measurements are essential to infer cosmological parameters from large area weak gravitational lensing studies. The compact diffraction-limited point spread function (PSF) in space-based observations is greatly beneficial, but its chromaticity for a broad-band observation can lead to new subtle effects that could hitherto be ignored…
Radio/X-ray monitoring of the broad-line radio galaxy 3C 382. High-energy view with XMM-Newton and NuSTAR
Bianchi, S.; Cappi, M.; Ponti, G. +14 more
We present the analysis of five joint XMM-Newton/NuSTAR observations, 20 ks each and separated by 12 days, of the broad-line radio galaxy 3C 382. The data were obtained as part of a campaign performed in September-October 2016 simultaneously with Very Long Baseline Array. The radio data and their relation with the X-ray ones will be discussed in a…