Search Publications
The 2008 October Swift detection of X-ray bursts/outburst from the transient SGR-like AXP 1E1547.0-5408
Campana, S.; Tiengo, A.; de Luca, A. +17 more
We report on the detailed study of the 2008 October outburst from the anomalous X-ray pulsar 1E1547.0-5408 discovered through the Swift/Burst Alert Telescope (BAT) detection of soft gamma-ray repeater like short X-ray bursts on 2008 October 3. The Swift/X-ray Telescope (XRT) started observing the source after less than 100s since the BAT trigger, …
Cold dust and young starbursts: spectral energy distributions of Herschel SPIRE sources from the HerMES survey
Aussel, H.; Elbaz, D.; Valtchanov, I. +75 more
We present spectral energy distributions (SEDs) for 68 Herschel sources detected at 5σ at 250, 350 and 500 µm in the HerMES SWIRE-Lockman field. We explore whether existing models for starbursts, quiescent star-forming galaxies and active galactic nucleus dust tori are able to model the full range of SEDs measured with Herschel. We find that…
Accurate fundamental parameters for A-, F- and G-type Supergiants in the solar neighbourhood
Lambert, David L.; Lyubimkov, Leonid S.; Rostopchin, Sergey I. +2 more
The following parameters are determined for 63 Galactic supergiants in the solar neighbourhood: effective temperature Teff; surface gravity logg iron abundance logɛ(Fe) microturbulent parameter Vt; mass M/Msolar age t and distance d. A significant improvement in the accuracy of the determination of logg, and all pa…
Period-luminosity relations of pulsating M giants in the solar neighbourhood and the Magellanic Clouds
Derekas, A.; Kiss, L. L.; Bedding, T. R. +3 more
We analyse the results of a 5.5-yr photometric campaign that monitored 247 southern, semiregular variables with relatively precise Hipparcos parallaxes to demonstrate an unambiguous detection of red giant branch (RGB) pulsations in the solar neighbourhood. We show that Sequence A' contains a mixture of asymptotic giant branch and RGB stars, as ind…
Demystifying the coronal-line region of active galactic nuclei: spatially resolved spectroscopy with the Hubble Space Telescope
Komossa, S.; Mazzalay, Ximena; Rodríguez-Ardila, Alberto
We present an analysis of Space Telescope Imaging Spectrograph (STIS)/Hubble Space Telescope optical spectra of a sample of 10 Seyfert galaxies aimed at studying the structure and physical properties of the coronal-line region (CLR). The high spatial resolution provided by STIS allowed us to resolve the CLR and obtain key information about the kin…
Polarized QPOs from the INTEGRAL polar IGRJ14536-5522 (=Swift J1453.4-5524)
O'Donoghue, Darragh; Buckley, David A. H.; Potter, Stephen B. +10 more
We report optical spectroscopy and high-speed photometry and polarimetry of the INTEGRAL source IGRJ14536-5522 (=Swift J1453.4-5524). The photometry, polarimetry and spectroscopy are modulated on an orbital period of 3.1564(1) h. Orbital circularly polarized modulations are seen from ~0 to ~ -18 per cent, unambiguously identifying IGRJ14536-5522 a…
Multiwavelength observations of 1RXH J173523.7-354013: revealing an unusual bursting neutron star
D'Avanzo, P.; de Luca, A.; Degenaar, N. +14 more
On 2008 May 14, the Burst Alert Telescope onboard the Swift mission triggered on a type-I X-ray burst from the previously unclassified ROSAT object 1RXH J173523.7-354013, establishing the source as a neutron star X-ray binary. We report on X-ray, optical and near-infrared observations of this system. The X-ray burst had a duration of ~2 h and belo…
Explaining the hard excesses in active galactic nuclei
Fabian, A. C.; Reis, R. C.; Walton, D. J.
A common model invoked to describe the X-ray spectra of active galaxies includes a relativistically blurred reflection component, which in some cases can be the dominant contributor to the received flux. Alternative interpretations are often based around complex absorption, and to date it has proven difficult to determine between these two viable …
VLT diffraction-limited imaging at 11 and 18µm of the nearest active galactic nuclei
Siebenmorgen, R.; Prieto, M. A.; Reunanen, J.
Mid-infrared (mid-IR) imaging at resolutions of 300mas of the central kpc region of 13 nearby, well-known active galaxies is presented. The bulk of the mid-IR emission is concentrated on an unresolved central source within a size of less than 5-130pc, depending on the object distance. Further resolved emission is detected in 70 per cent of the sam…
The evolutionary sequence of submillimetre galaxies: from diffuse discs to massive compact ellipticals?
Conselice, C. J.; Buitrago, F.; Ricciardelli, E. +1 more
The population of compact massive galaxies observed at z > 1 is hypothesized, both observationally and in simulations, to be merger remnants of gas-rich disc galaxies. To probe such a scenario, we analyse a sample of 12 gas-rich and active star-forming submillimetre galaxies (SMGs) at 1.8 < z < 3. We present a structural and size measurem…