Search Publications
Modelling the evolution of a comet subsurface: implications for 67P/Churyumov-Gerasimenko
Guilbert-Lepoutre, Aurélie; Rosenberg, Eric D.; Prialnik, Dina +1 more
Modelling the evolution of comets is a complex task aiming at providing constraints on physical processes and internal properties that are inaccessible to observations, although they could potentially bring key elements to our understanding of the origins of these primitive objects. This field has made a tremendous step forward in the post-Giotto …
Sublimation of icy aggregates in the coma of comet 67P/Churyumov-Gerasimenko detected with the OSIRIS cameras on board Rosetta
Jorda, L.; Lamy, P. L.; Lara, L. M. +58 more
Beginning in 2014 March, the OSIRIS (Optical, Spectroscopic, and Infrared Remote Imaging System) cameras began capturing images of the nucleus and coma (gas and dust) of comet 67P/Churyumov-Gerasimenko using both the wide angle camera (WAC) and the narrow angle camera (NAC). The many observations taken since July of 2014 have been used to study th…
The Gaia spectrophotometric standard stars survey - III. Short-term variability monitoring
Jordi, C.; Figueras, F.; Marinoni, S. +14 more
We present the results of the short-term constancy monitoring of candidate Gaia Spectrophotometric Standard Stars (SPSS). We obtained time series of typically 1.24 h - with sampling periods from 1-3 min to a few hours, depending on the case - to monitor the constancy of our candidate SPSS down to 10 mmag, as required for the calibration of Gaia ph…
The Chandra ACIS Timing Survey Project: glimpsing a sample of faint X-ray pulsators
Sidoli, L.; Esposito, P.; Israel, G. L. +1 more
We report on the discovery of 41 new pulsating sources in the data of the Chandra Advanced CCD Imaging Spectrometer, which is sensitive to X-ray photons in the 0.3-10 keV band. The archival data of the first 15 yr of Chandra observations were retrieved and analysed by means of fast Fourier transforms, employing a peak-detection algorithm able to s…
The SLUGGS survey*: exploring the globular cluster systems of the Leo II group and their global relationships
Spitler, Lee R.; Forbes, Duncan A.; Romanowsky, Aaron J. +6 more
We present an investigation of the globular cluster (GC) systems of NGC 3607 and NGC 3608 as part of the ongoing SLUGGS (SAGES Legacy Unifying Globulars and GalaxieS) survey. We use wide-field imaging data from the Subaru telescope in the g, r and I filters to analyse the radial density, colour and azimuthal distributions of both GC systems. With …
Galactic Centre hypershell model for the North Polar Spurs
Kataoka, J.; Matsui, H.; Nakashima, S. +5 more
The bipolar-hypershell (BHS) model for the North Polar Spurs (NPS-E, -W, and Loop I) and counter southern spurs (SPS-E and -W) is revisited based on numerical hydrodynamical simulations. Propagations of shock waves produced by energetic explosive events in the Galactic Centre are examined. Distributions of soft X-ray brightness on the sky at 0.25,…
Searching for intermediate-mass black holes in globular clusters with gravitational microlensing
Kains, N.; Bramich, D. M.; Sahu, K. C. +1 more
We discuss the potential of the gravitational microlensing method as a unique tool to detect unambiguous signals caused by intermediate-mass black holes in globular clusters. We select clusters near the line of sight to the Galactic bulge and the Small Magellanic Cloud, estimate the density of background stars for each of them, and carry out simul…
Relativistic Fe Kα line study in Seyfert 1 galaxies observed with Suzaku
Nandra, K.; Ponti, G.; Mantovani, G.
We present an analysis of a sample of Seyfert 1 galaxies observed with Suzaku. The aim of this work is to examine critically the evidence for a relativistic Fe Kα line in the X-ray spectra of these active galactic nuclei. The sample was compiled from those sources in which a relativistic component was missing in at least one XMM-Newton observation…
The variable spin-down rate of the transient magnetar XTE J1810-197
Pintore, Fabio; Mereghetti, Sandro; Esposito, Paolo +7 more
We have analysed XMM-Newton and Chandra observations of the transient magnetar XTE J1810-197 spanning more than 11 yr, from the initial phases of the 2003 outburst to the current quiescent level. We investigated the evolution of the pulsar spin period and we found evidence for two distinct regimes: during the outburst decay, dot{ν } was highly var…
Solo dwarfs I: survey introduction and first results for the Sagittarius dwarf irregular galaxy
Côté, P.; Battaglia, G.; Lewis, G. F. +6 more
We introduce the Solitary Local dwarfs survey (Solo), a wide-field photometric study targeting every isolated dwarf galaxy within 3 Mpc of the Milky Way. Solo is based on (u)gi multiband imaging from Canada-France-Hawaii Telescope/MegaCam for northern targets, and Magellan/Megacam for southern targets. All galaxies fainter than MV ≃ -18…