Search Publications
X-ray absorption towards high-redshift sources: probing the intergalactic medium with blazars
Campana, S.; Ghisellini, G.; Salvaterra, R. +1 more
The role played by the intergalactic medium (IGM) in the X-ray absorption towards high-redshift sources has recently drawn more attention in spectral analysis studies. Here, we study the X-ray absorption towards 15 flat-spectrum radio quasars at z > 2, relying on high counting statistic (≳10 000 photons) provided by XMM-Newton, with additional …
Gaia DR2 view of the Lupus V-VI clouds: The candidate diskless young stellar objects are mainly background contaminants
Prusti, T.; Fedele, D.; Alcalá, J. M. +10 more
Extensive surveys of star-forming regions with Spitzer have revealed populations of disk-bearing young stellar objects. These have provided crucial constraints, such as the timescale of dispersal of protoplanetary disks, obtained by carefully combining infrared data with spectroscopic or X-ray data. While observations in various regions agree with…
Solar wind dynamics around a comet. A 2D semi-analytical kinetic model
Holmström, M.; Behar, E.; Nilsson, H. +5 more
Aims: We aim at analytically modelling the solar wind proton trajectories during their interaction with a partially ionised cometary atmosphere, not in terms of bulk properties of the flow but in terms of single particle dynamics.
Methods: We first derive a generalised gyromotion, in which the electric field is reduced to its motional co…
BGM FASt: Besançon Galaxy Model for big data. Simultaneous inference of the IMF, SFH, and density in the solar neighbourhood
Figueras, F.; Antoja, T.; Mor, R. +1 more
Aims: We develop a new theoretical framework to generate Besançon Galaxy Model Fast Approximate Simulations (BGM FASt) to address fundamental questions of the Galactic structure and evolution performing multi-parameter inference. As a first application of our strategy we simultaneously infer the initial-mass function (IMF), the star formation…
Studying bright variable stars with the Multi-site All-Sky CAmeRA (MASCARA)
Snellen, I. A. G.; Van Eylen, V.; Pollacco, D. +6 more
Context. The Multi-site All-Sky CAmeRA (MASCARA) aims to find the brightest transiting planet systems by monitoring the full sky at magnitudes 4 < V < 8.4, taking data every 6.4 s. The northern station has been operational on La Palma since February 2015. These data can also be used for other scientific purposes, such as the study of variabl…
Messier 81's Planck view versus its halo mapping
Nucita, A. A.; De Paolis, F.; Ingrosso, G. +8 more
This paper is a follow-up of a previous paper about the M 82 galaxy and its halo based on Planck observations. As in the case of M 82, a substantial north-south and east-west temperature asymmetry is also found for the M 81 galaxy, extending up to galactocentric distances of about 1.5°. The temperature asymmetry is almost frequency independent and…
Bipolar H II regions. II. Morphologies and star formation in their vicinities
Zavagno, A.; Samal, M. R.; Molinari, S. +3 more
Aims: We aim to identify bipolar Galactic H II regions and to understand their parental cloud structures, morphologies, evolution, and impact on the formation of new generations of stars.
Methods: We use the Spitzer-GLIMPSE, Spitzer-MIPSGAL, and Herschel-Hi-GAL surveys to identify bipolar H II regions and to examine their morphologies. W…
Supergiant fast X-ray transients versus classical supergiant high mass X-ray binaries: Does the difference lie in the companion wind?
Bozzo, E.; Paul, B.; Pradhan, P.
We present a comparative study of stellar winds in classical supergiant high mass X-ray binaries (SgXBs) and supergiant fast X-ray transients (SFXTs) based on the analysis of publicly available out-of-eclipse observations performed with Suzaku and XMM-Newton. Our data set includes 55 observations of classical SgXBs and 21 observations of SFXTs. We…
The Serpens filament at the onset of slightly supercritical collapse
Menten, K. M.; Henkel, C.; Gong, Y. +5 more
The Serpens filament, as one of the nearest infrared dark clouds, is regarded as a pristine filament at a very early evolutionary stage of star formation. In order to study its molecular content and dynamical state, we mapped this filament in seven species: C18O, HCO+, HNC, HCN, N2H+, CS, and CH3
Emission of solar chromospheric and transition region features related to the underlying magnetic field
Barczynski, K.; Peter, H.; Chitta, L. P. +1 more
Context. The emission of the upper atmosphere of the Sun is closely related to magnetic field concentrations at the solar surface.
Aims: It is well established that this relation between chromospheric emission and magnetic field is nonlinear. Here we investigate systematically how this relation, characterised by the exponent of a power-law fi…