Search Publications
Polarization of seven MBM clouds at high Galactic latitude
Neha, S.; Soam, A.; Maheswar, G. +1 more
We made R-band polarization measurements of 234 stars towards the direction of the MBM 33-39 cloud complex. The distance of the MBM 33-39 complex was determined as 120 ± 10 pc using polarization results and near-infrared photometry from the 2MASS survey. The magnetic field geometry of the individual clouds inferred from our polarimetric results re…
Gaian bottlenecks and planetary habitability maintained by evolving model biospheres: the ExoGaia model
Nicholson, Arwen E.; Wilkinson, David M.; Williams, Hywel T. P. +1 more
The search for habitable exoplanets inspires the question - how do habitable planets form? Planet habitability models traditionally focus on abiotic processes and neglect a biotic response to changing conditions on an inhabited planet. The Gaia hypothesis postulates that life influences the Earth's feedback mechanisms to form a self-regulating sys…
Polarization light curve modelling of corotating interaction regions in the wind of the Wolf-Rayet star WR 6
Ignace, Richard; St-Louis, N.; Tremblay, Patrick
The intriguing WN4b star WR 6 has been known to display epoch-dependent spectroscopic, photometric and polarimetric variability for several decades. In this paper, we set out to verify if a simplified analytical model in which corotating interaction regions (CIRs) threading an otherwise spherical wind is able to reproduce the many broad-band conti…
The PAU Survey: a forward modeling approach for narrow-band imaging
Tortorelli, Luca; Della Bruna, Lorenza; Herbel, Jörg +18 more
Weak gravitational lensing is a powerful probe of the dark sector, once measurement systematic errors can be controlled. In [1], a calibration method based on forward modeling, called MCCL, was proposed. This relies on fast image simulations (e.g., UFig [2,3]}) that capture the key features of galaxy populations and measurement effects. The MCCL a…
Models of bright storm clouds and related dark ovals in Saturn's Storm Alley as constrained by 2008 Cassini/VIMS spectra
Baines, K. H.; Sromovsky, L. A.; Fry, P. M.
A 5° latitude band on Saturn centered near planetocentric latitude 36°S is known as "Storm Alley" because it has been for several extended periods a site of frequent lightning activity and associated thunderstorms, first identified by Porco et al. (2005). The thunderstorms appeared as bright clouds at short and long continuum wavelengths, and over…
Deep XMM-Newton observations of the northern disc of M 31. I. Source catalogue
Williams, Benjamin F.; Sasaki, Manami; Haberl, Frank +12 more
Context. We carried out new observations of two fields in the star-forming northern ring of M 31 with XMM-Newton with each one of them consisting of two exposures of about 100 ks each. A previous XMM-Newton survey of the entire M 31 galaxy revealed extended diffuse X-ray emission in these regions.
Aims: We study the population of X-ray source…
Supermirror design for Hard X-Ray Telescopes on-board Hitomi (ASTRO-H)
Maeda, Yoshitomo; Ishida, Manabu; Kunieda, Hideyo +14 more
We designed depth-graded multilayers, so-called supermirrors, with platinum/carbon (Pt/C) layer pairs for the Hard X-Ray Telescope (HXT) that was on-board the sixth Japanese X-Ray Astronomy Satellite Hitomi (ASTRO-H). The HXT has multinested thin foil optics, and the grazing angles of the x-ray mirrors are 0.07 to 0.27 deg. Supermirrors for HXTs a…
A chemical study of M67 candidate blue stragglers and evolved blue stragglers observed with APOGEE DR14
Grebel, Eva K.; Pasquali, Anna; Caffau, Elisabetta +1 more
Within the variety of objects populating stellar clusters, blue straggler stars (BSSs) are among the most puzzling ones. BSSs are commonly found in globular clusters, but they are also known to populate open clusters of the Milky Way. Two main theoretical scenarios (collisions and mass transfer) have been suggested to explain their formation, alth…
Thermal Stability of Water Ice in Ceres' Craters: The Case of Juling Crater
Raponi, A.; Tosi, F.; De Sanctis, M. C. +4 more
Ice thermal stability on the surface of the dwarf planet Ceres is an important issue linked to the Herschel observations of water vapor around Ceres. One of these surficial ice deposits is located within the 20-km crater Juling (35°S, 168°E). The study of water ice exposure in this specific crater is particularly interesting because it has been ob…
A census of radio-selected AGNs on the COSMOS field and of their FIR properties
Popesso, P.; Salvato, M.; Brusa, M. +1 more
We use the new catalogue by Laigle et al. to provide a full census of VLA-COSMOS radio sources. We identify 90 per cent of such sources and sub-divide them into active galactic nuclei (AGNs) and star-forming galaxies on the basis of their radio luminosity. The AGN sample is complete with respect to radio selection at all z ≲ 3.5. Out of 704 AGNs, …