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A new perspective on the irregular satellites of Saturn - II. Dynamical and physical origin
Marzari, F.; Tosi, F.; Turrini, D.
The origin of the irregular satellites of the giant planets has been long debated since their discovery. Their dynamical features argue against an in situ formation suggesting that they are captured bodies, yet there is no global consensus on the physical process at the basis of their capture. In this paper, we explore the collisional capture scen…
X-ray spectral evolution of the extragalactic Z source LMC X-2
Misra, R.; Agrawal, V. K.
We present the results obtained by a detailed study of the extragalactic Z source LMC X-2, using broad-band Suzaku data and a large (~750ks) data set obtained with the proportional counter array (PCA) onboard the Rossi X-ray Timing Experiment (RXTE). The PCA data allow the study of the complete spectral evolution along the horizontal, normal and f…
ISO observation of molecular hydrogen and fine-structure lines in the photodissociation region IC63
van Dishoeck, E. F.; Bell, T.; Viti, S. +2 more
We wish to constrain the main physical properties of the photodissociation region (PDR) IC63. We present the results of a survey for the lowest pure-rotational lines of H2 with the Short Wavelength Spectrometer and for the major fine-structure cooling lines of OI at 63 and 145µm and CII at 157.7µm with the Long Wavelength Sp…
High-speed knots in the hourglass-shaped planetary nebula Hubble 12
Pollacco, D.; López, J. A.; Rushton, A. P. +5 more
We present a detailed kinematical analysis of the young compact hourglass-shaped planetary nebula Hb 12. We performed optical imaging and long-slit spectroscopy of Hb 12 using the Manchester echelle spectrometer with the 2.1-m San Pedro Mártir telescope. We reveal, for the first time, the presence of end caps (or knots) aligned with the bipolar lo…
Peculiar nature of hard X-ray eclipse in SS433 from INTEGRAL observations
Sunyaev, R. A.; Postnov, K. A.; Cherepashchuk, A. M. +2 more
The analysis of hard X-ray INTEGRAL observations (2003-2008) of superaccreting Galactic microquasar SS433 at precessional phases of the source with the maximum disc opening angle is carried out. It is found that the shape and width of the primary X-ray eclipse are strongly variable, suggesting additional absorption in dense stellar wind and gas ou…
The radius and other fundamental parameters of the F9V star β Virginis
Stello, D.; Tuthill, P. G.; Lacour, S. +10 more
We have used the Sydney University Stellar Interferometer (SUSI) to measure the angular diameter of the F9V star β Virginis (β Vir). After correcting for limb darkening and combining with the revised Hipparcos parallax, we derive a radius of 1.703 +/- 0.022Rsolar (1.3 per cent). We have also calculated the bolometric flux from published…
Superorbital variability in hard X-rays
Farrell, S. A.; Barret, D.; Skinner, G. K.
We present the results of a study with the Swift Burst Alert Telescope in the 14-195 keV range of the long-term variability of five low-mass X-ray binaries with reported or suspected superorbital periods - 4U 1636-536, 4U 1820-303, 4U 1916-053, Cyg X-2 and Sco X-1. No significant persistent periodic modulation was detected around the previously re…
The globular clusters-stellar haloes connection in early-type galaxies
Forte, Juan C.; Vega, E. Irene; Faifer, Favio
This paper explores if, and to what an extent, the stellar populations of early-type galaxies can be traced through the colour distribution of their globular cluster (GC) systems. The analysis, based on a galaxy sample from the Virgo Advanced Camera for Surveys data, is an extension of a previous approach that has been successful in the cases of t…
Evolution of the X-ray luminosity in young HII galaxies
Nandra, K.; Rosa González, D.; Terlevich, E. +5 more
In an effort to understand the correlation between X-ray emission and present star formation rate, we obtained XMM-Newton data to estimate the X-ray luminosities of a sample of actively star-forming HII galaxies. The obtained X-ray luminosities are compared to other well-known tracers of star formation activity such as the far-infrared and the ult…
Photometric selection of z ~ 5 Lyman break galaxies in the ESO Remote Galaxy Survey
Bremer, M. N.; Lehnert, M. D.; Stanway, E. R. +2 more
We describe the selection of a sample of photometrically defined Lyman break galaxies (LBGs) at z ~ 5 using the multiwavelength imaging data of the ESO (European Southern Observatory) Remote Galaxy Survey. The data are drawn from 10 widely separated fields covering a total sky area of 275arcmin2. Starting with a simple colour (R - I >…