Search Publications
Dynamics and metallicity of far-infrared selected galaxies
Lutz, D.; Maiolino, R.; Marconi, A. +4 more
We present near-infrared integral field spectroscopy of 10 Herschel selected galaxies at z ∼ 1.5. From detailed mapping of the Hα and [N II] emission lines, we trace the dynamics, star formation rates, metallicities and also investigate gas fractions for these galaxies. For a few galaxies, the distribution of star formation as traced by Hα only tr…
The candidate luminous blue variable G79.29+0.46: a comprehensive study of its ejecta through a multiwavelength analysis
Umana, G.; Agliozzo, C.; Noriega-Crespo, A. +5 more
We present a multiwavelength analysis of the nebula around the candidate luminous blue variable G79.29+0.46. The study is based on our radio observations performed at the Expanded Very Large Array and at the Green Bank Telescope and on archival infrared data sets, including recent images obtained by the Herschel Space Observatory. We confirm that …
UV spectral analysis of very hot H-deficient [WCE]-type central stars of planetary nebulae: NGC 2867, NGC 5189, NGC 6905, Pb 6 and Sand 3
Bianchi, Luciana; Keller, Graziela R.; Maciel, Walter J.
We analysed ultraviolet Far Ultraviolet Spectroscopic Explorer, International Ultraviolet Explorer, and Hubble Space Telescope/Space Telescope Imaging Spectrograph spectra of five of the hottest [WCE]-type central stars of planetary nebulae: NGC 2867, NGC 5189, NGC 6905, Pb 6, and Sand 3. The analysis leveraged on our grid of cmfgen synthetic spec…
Bursting emission from PSR B0611+22
Lorimer, D. R.; Seymour, A. D.; Ridley, J. P.
Over the past decade it has become apparent that a class of `bursting pulsars' exists with the discovery of PSR J1752+2359 and PSR J1938+2213. In these pulsars, a sharp increase in the emission is observed that then tends to systematically drop-off from pulse-to-pulse. In this paper we describe the discovery of such a relationship in high-sensitiv…
The XMM-Newton view of the radio-loud narrow-line Seyfert 1 galaxy PMN J0948+0022
Bhatt, Himali; Bhattacharyya, Subir; Bhatt, Nilay +1 more
We analysed the archival XMM-Newton data of the radio-loud narrow-line Seyfert 1 galaxy PMN J0948+0022 in the energy range 0.3-10.0 keV. The X-ray data reveal that the spectrum in the 0.3-10.0 keV energy band is not a simple power law as previously described in the literature. Instead it consists of a power law with soft excess below 2.5 keV. The …
Detailed modelling of a large sample of Herschel sources in the Lockman Hole: identification of cold dust and of lensing candidates through their anomalous SEDs★
Valtchanov, Ivan; Oliver, Seb; Vaccari, Mattia +12 more
We have studied in detail a sample of 967 SPIRE sources with 5σ detections at 350 and 500 µm and associations with Spitzer-SWIRE 24 µm galaxies in the HerMES-Lockman survey area, fitting their mid- and far-infrared, and submillimetre, spectral energy distributions (SEDs) in an automatic search with a set of six infrared templates. For …
The Lutz-Kelker paradox.
Francis, C.
The Lutz-Kelker correction is intended to give an unbiased estimate for stellar parallaxes and magnitudes, but it is shown explicitly that it does not. This paradox results from the application of an argument about sample statistics to the treatment of individual stars, and involves the erroneous use of a frequency distribution in the manner of a …
An extremely low gas-to-dust ratio in the dust-lane lenticular galaxy NGC 5485.
Fritz, J.; Baes, M.; Viaene, S. +7 more
Evidence is mounting that a significant fraction of the early-type galaxy population contains substantial reservoirs of cold interstellar gas and dust. We investigate the gas and dust in NGC 5485, an early-type galaxy with a prominent minor-axis dust lane. Using new Herschel PACS and SPIRE imaging data, we detect 3.8 × 106 M⊙…
What obscures low-X-ray-scattering active galactic nuclei
Hönig, S. F.; Gandhi, P.; Asmus, D. +4 more
X-ray surveys have revealed a new class of active galactic nuclei (AGN) with a very low observed fraction of scattered soft X-rays, fscat <0.5 per cent. Based on X-ray modelling, these `X-ray new-type', or low observed X-ray-scattering (hereafter, `low-scattering') sources have been interpreted as deeply buried AGN with a high coveri…
The Galactic plane at faint X-ray fluxes - II. Stacked X-ray spectra of a sample of serendipitous XMM-Newton sources
Pérez-Ramírez, D.; Warwick, R. S.; Byckling, K.
We have investigated the X-ray spectral properties of a sample of 138 X-ray sources detected serendipitously in XMM-Newton observations of the Galactic plane, at an intermediate to faint flux level. We divide our sample into five subgroups according to the spectral hardness of the sources, and stack (i.e. co-add) the individual source spectra with…