Search Publications

The infrared view of dust and molecules around V4334 Sgr (Sakurai's object): a 20-yr retrospective

Gehrz, R. D.; Joyce, R. R.; Eyres, S. P. S. +16 more

We present an analysis of the evolution of circumstellar dust and molecules in the environment of the very late thermal pulse object V4334 Sgr (Sakurai's object) over an ∼20-yr period, drawing on ground-, airborne-, and space-based infrared photometry and spectroscopy. The dust emission, which started in 1997, resembles a blackbody that cooled fro…

CCD VI time-series of the extremely metal-poor globular cluster M92: revisiting its variable star population

Arellano Ferro, A.; Deras, D.; Yepez, M. A.

We present an analysis of VI CCD time-series photometry of the Oo II type globular cluster M92. The variable star population of the cluster is studied with the aim of revising their classifications, identifications, frequency spectra, and to select indicators of the parental cluster metallicity and distance. The Fourier decomposition of RR Lyrae l…

67P/Churyumov-Gerasimenko's dust activity from pre- to post-perihelion as detected by Rosetta/GIADA

Fulle, M.; Güttler, C.; Tubiana, C. +18 more

We characterized the 67P/Churyumov-Gerasimenko's dust activity, by analysing individual dust particle velocity and momentum measurements of Grain Impact Analyser and Dust Accumulator (GIADA), the dust detector onboard the ESA/Rosetta spacecraft, collecting dust from tens to hundreds of kilometres from the nucleus. Specifically, we developed a proc…

A broad-band X-ray spectral study of the Seyfert 1 galaxy ESO 141-G055 with XMM-Newton and NuSTAR

Laha, Sibasish; Ghosh, Ritesh

We have extensively studied the broad--band X-ray spectra of the source ESO 141-G055 using all available XMM-Newton and NuSTAR observations. We detect a prominent soft excess below $2\rm \, \, {\rm keV}$ , a narrow Fe line, and a Compton hump ( $\gt 10\rm \, \, {\rm keV}$ ). The origin of the soft excess is still debated. We used two models to des…

Galaxy and mass assembly: luminosity and stellar mass functions in GAMA groups

Wang, L.; Brough, S.; Holwerda, B. W. +14 more

How do galaxy properties (such as stellar mass, luminosity, star formation rate, and morphology) and their evolution depend on the mass of their host dark matter halo? Using the Galaxy and Mass Assembly group catalogue, we address this question by exploring the dependence on host halo mass of the luminosity function (LF) and stellar mass function …

Linking the small-scale relativistic winds and the large-scale molecular outflows in the z = 1.51 lensed quasar HS 0810+2554

Cappi, M.; Vignali, C.; Comastri, A. +7 more

We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of the quadruply lensed z = 1.51 quasar HS 0810+2554 which provide useful insight on the kinematics and morphology of the CO molecular gas and the ∼ 2 mm-continuum emission in the quasar host galaxy. Lens modelling of the mm-continuum and the spectrally integrated CO(J = 3…

An ancient double degenerate merger in the Milky Way halo

Vennes, Stéphane; Ferrario, Lilia; Kawka, Adela

We present an analysis and re-appraisal of the massive, carbon-enriched (DQ) white dwarf (WD) LP 93-21. Its high mass ( ≈1.1 M_⊙) and membership to the class of warm DQ WDs, combined with its peculiar halo kinematics suggest that this object is the product of an ancient stellar merger event, most likely that of two WDs. Furthermore, the …

The Smallest Scale of Hierarchy survey (SSH) - I. Survey description

Cignoni, M.; Tosi, M.; Bellazzini, M. +7 more

The Smallest Scale of Hierarchy (SSH) survey is an ongoing strategic large program at the Large Binocular Telescope, aimed at the detection of faint stellar streams and satellites around 45 late-type dwarf galaxies located in the Local Universe within ≃10 Mpc. SSH exploits the wide-field, deep photometry provided by the Large Binocular Cameras in …

Erratum: The Herschel Bright Sources (HerBS): sample definition and SCUBA-2 observations

Ivison, R. J.; Omont, A.; Clements, D. L. +20 more

A study of the physical properties of SB2s with both the visual and spectroscopic orbits

Tamazian, Vakhtang S.; Campo, Pedro P.; Piccotti, Luca +4 more

The study of a selected set of 69 double-lined spectroscopic binaries (SB2) with well-defined visual and spectroscopic orbits was carried out. The orbital parallax, the mass, the colour, and the luminosity of each component were derived from observational data for almost all of these systems. We have also obtained an independent estimation of the …