Search Publications
Multi-wavelength observations of IGR J17544-2619 from quiescence to outburst
Campana, S.; Stella, L.; Chaty, S. +12 more
In this paper we report on a long multi-wavelength observational campaign of the supergiant fast X-ray transient prototype IGR J17544-2619. A 150 ks-long observation was carried out simultaneously with XMM-Newton and NuSTAR, catching the source in an initial faint X-ray state and then undergoing a bright X-ray outburst lasting approximately 7 ks. …
Small particles and self-gravity wakes in Saturn's rings from UVIS and VIMS stellar occultations
Nicholson, Philip D.; Hedman, Matthew M.; Colwell, Joshua E. +2 more
The distribution of particle sizes in Saturn's rings roughly follows a truncated inverse power-law. Though it is well known that differential optical depths provide a way to probe the parameters of size distribution (i.e. Zebker et al. [1985] Icarus, 64, 531-548), the technique is complicated by the presence of self-gravity wakes which introduce a…
Morphological evolution of cluster red sequence galaxies in the past 9 Gyr
De Propris, Roberto; Phillipps, Steven; Bremer, Malcolm N.
Galaxies arrive on the red sequences of clusters at high redshift (z > 1) once their star formation is quenched and evolve passively thereafter. However, we have previously found that cluster red sequence galaxies (CRSGs) undergo significant morphological evolution subsequent to the cessation of star formation, at some point in the past 9-10 Gy…
Magnetic field geometry of an unusual cometary cloud Gal 110-13
Neha, S.; Soam, A.; Maheswar, G. +2 more
Aims: We carried out optical polarimetry of an isolated cloud, Gal 110-13, to map the plane-of-the-sky magnetic field geometry. The main aim of the study is to understand the most plausible mechanism responsible for the unusual cometary shape of the cloud in the context of its magnetic field geometry.
Methods: When unpolarized starlight …
Luminous blue variables: An imaging perspective on their binarity and near environment
Rivinius, Thomas; Baade, Dietrich; Mérand, Antoine +18 more
Context. Luminous blue variables (LBVs) are rare massive stars with very high luminosity. They are characterized by strong photometric and spectroscopic variability related to transient eruptions. The mechanisms at the origin of these eruptions is not well known. In addition, their formation is still problematic and the presence of a companion cou…
EXTraS discovery of an 1.2-s X-ray pulsar in M 31
Salvaterra, R.; Haberl, F.; Read, A. M. +13 more
During a search for coherent signals in the X-ray archival data of XMM-Newton, we discovered a modulation at 1.2 s in 3XMM J004301.4+413017 (3X J0043), a source lying in the direction of an external arm of M 31. This short period indicates a neutron star (NS). Between 2000 and 2013, the position of 3X J0043 was imaged by public XMM-Newton observat…
X-ray timing analysis of the quasar PG 1211+143
Vaughan, S.; Reeves, J. N.; Pounds, K. +1 more
We report on a timing analysis of a new ∼630 ks XMM-Newton observation of the quasar, PG 1211+143. We find a well-defined X-ray power spectrum with a well-detected bend at ∼7 × 10-5 Hz, consistent with the established tbend-MBH correlation for luminous, accreting black holes. We find the linear rms-flux relation co…
A radiative transfer model to treat infrared molecular excitation in cometary atmospheres
Bockelée-Morvan, D.; Debout, V.; Zakharov, V.
The exospheres of small Solar System bodies are now observed with high spatial resolution from space missions. Interpreting infrared spectra of cometary gases obtained with the VIRTIS experiment onboard the Rosetta cometary mission requires detailed modeling of infrared fluorescence emission in optically thick conditions. Efficient computing metho…
Constraining quantum collapse inflationary models with CMB data
Benetti, Micol; Alcaniz, Jailson S.; Landau, Susana J.
The hypothesis of the self-induced collapse of the inflaton wave function was proposed as responsible for the emergence of inhomogeneity and anisotropy at all scales. This proposal was studied within an almost de Sitter space-time approximation for the background, which led to a perfect scale-invariant power spectrum, and also for a quasi-de Sitte…
The bi-directional moving structures in a coronal bright point
Li, Dong; Ning, Zongjun; Su, Yingna
We report the bi-directional moving structures in a coronal bright point (CBP) on 2015 July 14. It is observed by the Atmospheric Imaging Assembly (AIA) onboard Solar Dynamics Observatory (SDO). This CBP has a lifetime of ∼10 minutes, and a curved shape. The observations show that many bright structures are moving intermittently outward from the C…