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The X-ray spectrum of the black hole candidate Swift J1753.5-0127
Mostafa, Reham; Mendez, Mariano; Hiemstra, Beike +4 more
We present a spectral analysis of the black hole candidate and X-ray transient source Swift J1753.5-0127 making use of simultaneous observations of XMM-Newton and Rossi X-ray Timing Explorer in 2006, when the source was in outburst. The aim of this paper is to test whether a thermal component due to the accretion disc is present in the X-ray spect…
High-angular-resolution stellar imaging with occultations from the Cassini spacecraft - I. Observational technique
Nicholson, Philip D.; Hedman, Matthew M.; Lloyd, James P. +2 more
We present novel observations utilizing the Cassini spacecraft to conduct an observing campaign for stellar astronomy from a vantage point in the outer Solar system. By exploiting occultation events in which Mira passed behind the Saturnian ring plane as viewed by Cassini, parametric imaging data were recovered spanning the near-infrared. From thi…
New VLT observations of the Fermi pulsar PSR J1048-5832
de Luca, A.; Marelli, M.; Razzano, M. +1 more
PSR J1048-5832 is a Vela-like (P = 123.6 ms; τ ∼ 20.3 kyr) γ-ray pulsar detected by Fermi, at a distance of ∼2.7 kpc and with a rotational energy loss rate dot{E}_SD ∼ 2 × 10^{36} erg s-1. The PSR J1048-5832 field has been observed with the Very Large Telescope (VLT) in the V and R bands. We used these data to determine the colour of th…
A young hierarchical triple system harbouring a candidate debris disc
Henning, Th.; Olofsson, J.; Schlieder, J. E. +2 more
We report the detection of a wide young hierarchical triple system where the primary has a candidate debris disc. The primary, TYC 5241-986-1 A, is a known Tycho star which we classify as a late-K star with emission in the X-ray, near- and far-ultraviolet (UV) and Hα suggestive of youth. Its proper motion, photometric distance (65-105 pc) and radi…
Sunyaev-Zel'dovich observations with AMI of the hottest galaxy clusters detected in the XMM-Newton Cluster Survey
Romer, A. Kathy; AMI Consortium; Olamaie, Malak +18 more
We have obtained deep Sunyaev-Zel'dovich (SZ) observations towards 15 of the hottest XMM Cluster Survey (XCS) clusters that can be observed with the Arcminute Microkelvin Imager (AMI). We use a Bayesian analysis to quantify the significance of our SZ detections. We detect the SZ effect at high significance towards three of the clusters and at lowe…
Optical observations of PSR J0205+6449 - the next optical pulsar?
de Luca, A.; Rea, N.; Mignani, R. P. +3 more
PSR J0205+6449 is a young (∼5400 yr), Crab-like pulsar detected in radio and at X-ray and γ-ray energies and has the third largest spin-down flux among known rotation-powered pulsars. It also powers a bright synchrotron nebula detected in the optical and X-rays. At a distance of ∼3.2 kpc and with an extinction comparable to the Crab, PSR J0205+644…
Do gravitational lens galaxies have an excess of luminous substructure?
Treu, T.; Nierenberg, A. M.; Oldenburg, D.
Strong gravitational lensing can be used to directly measure the mass function of their satellites, thus testing one of the fundamental predictions of cold dark matter cosmological models. Given the importance of this test, it is essential to ensure that galaxies acting as strong lenses have dark and luminous satellites which are representative of…
Red bulgeless galaxies in SDSS DR7. Are there any AGN hosts?
Ribeiro, B.; Coelho, B.; Antón, S. +1 more
With the main goal of finding bulgeless galaxies harbouring supermassive black holes and showing, at most, just residual star formation activity, we have selected a sample of massive bulgeless red sequence galaxies from the Sloan Digital Sky Survey - Data Release 7 (SDSS DR7), based on the New York University Value-Added Galaxy Catalogue. Multiwav…
Properties and morphologies of Lyman break galaxies at z ∼ 1 in the Chandra Deep Field South, inferred from spectral energy distributions
Buat, V.; Burgarella, D.; Huang, J. -S. +3 more
After carefully cross-identifying previously discovered - and selected by the Galaxy Evolution Explorer (GALEX) - Lyman break galaxy (LBG) candidates one-to-one with their optical counterparts in the field of the Chandra Deep Field South (CDF-S), we re-estimate their photometric redshifts using multiwavelength data from ultraviolet and optical to …
Aligned grains and inferred toroidal magnetic fields in the envelopes of massive young stellar objects
Schneider, Glenn; Hines, Dean C.; Wolff, Michael J. +6 more
Massive young stellar objects (YSOs), like low-mass YSOs, are thought to be surrounded by optically thick envelopes and/or discs and are observed to have associated regions that produce polarized light at near-infrared wavelengths. These polarized regions are thought to be lower density outflows along the polar axes of the YSO envelopes. Using the…