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The highly obscured region around PKS 1343 - 601 . I. Galactic interstellar extinctions using DENIS galaxy colours
Woudt, P. A.; Schröder, A. C.; Kraan-Korteweg, R. C. +1 more
The highly obscured radio-bright galaxy
A longer XMM-Newton look at I Zwicky 1: variability of the X-ray continuum, absorption and iron Kα line
Brandt, W. N.; Papadakis, I. E.; Costantini, E. +3 more
We present the second XMM-Newton observation (85 ks) of the narrow-line Seyfert 1 galaxy (NLS1) IZw1 and describe its mean spectral and timing characteristics. On average, IZw1 is ~35 per cent dimmer in 2005 than in the shorter (20ks) 2002 observation. Between the two epochs the intrinsic absorption column density diminished, but there were also s…
On the effect of emission lines on UBVR photometry
Skopal, A.
We investigate the effect on the U, B, V, RC and RJ magnitudes of the removal of emission lines from a spectrum. We determined Δ m corrections from the ratio of fluxes with and without emission lines, transmitted from the object through a photometric filter. An exact and simplified approach for operative use was applied. The …
IGR J22517+2218=MG3 J225155+2217: A New Gamma-Ray Lighthouse in the Distant Universe
Gehrels, N.; Giommi, P.; Bird, A. J. +7 more
We report on the identification of a new soft gamma-ray source, namely, IGR J22517+2218, detected with INTEGRAL IBIS. The source, which has an observed 20-100 keV flux of ~4×10-11 ergs cm-2 s-1, is spatially coincident with MG3 J225155+2217, a quasar at z=3.668. The Swift XRT 0.5-10 keV continuum is flat (Γ=1.5) wi…
The High-Energy Emission of GRO J1655-40 As Revealed with INTEGRAL Spectroscopy of the 2005 Outburst
Díaz Trigo, M.; Wijnands, R.; Mas-Hesse, J. M. +10 more
We present broadband (3-500 keV) INTEGRAL X-ray spectra and X-ray/optical light curves of the luminous black hole X-ray transient and relativistic jet source GRO J1655-40. Our analysis covers four Target of Opportunity observations of the outburst that started in 2005 February. We find that the high-energy emission of GRO J1655-40 can be modeled w…
A Deep Chandra Look at the Low-LB Elliptical NGC 821: X-Ray Binaries, a Galactic Wind, and Emission at the Nucleus
Elvis, M.; Pellegrini, S.; Baldi, A. +4 more
The relatively nearby (distance = 24.1 Mpc) elliptical galaxy NGC 821, hosting a central massive black hole but inactive at all wavelengths, was observed with Chandra for a total exposure time of 230 ks in order to search for nuclear emission and gas available for accretion. Within its optical image, 41 sources were detected, with spectral propert…
The X-ray activity-rotation relation of T Tauri stars in Taurus-Auriga
Audard, M.; Güdel, M.; Grosso, N. +9 more
Context: The Taurus-Auriga star-forming complex hosts the only population of T Tauri stars in which an anticorrelation of X-ray activity and rotation period has been observed.
Aims: We aim to explain the origin of the X-ray activity-rotation relation in Taurus-Auriga. We also aim to put the X-ray activity of these stars into the context of the…
An Atlas of [N II] and [O III] Images and Spectra of Planetary Nebulae
Jaskot, Anne E.; Panagia, Nino; Balick, Bruce +10 more
We present an atlas of Hubble Space Telescope images and ground-based, long-slit, narrowband spectra centered on the 6584 Å line of [N II] and the 5007 Å line of [O III]. The spectra were obtained for a variety of slit positions across each target (as shown on the images) in an effort to account for nonspherical nebular geometries in a robust mann…
The extended structure of the remote cluster B514 in M 31. Detection of extra-tidal stars
Bellazzini, M.; Galleti, S.; Federici, L. +3 more
Aims:We present a study of the density profile of the remote M 31 globular cluster B514, obtained from HST/ACS observations.
Methods: By coupling analysis of the distribution of the integrated light with star counts, we are able to reliably follow the profile of the cluster out to r ~ 35 arcsec, corresponding to ≃130 pc. The profile is well-fi…
Separation of the visible and dark matter in the Einstein ring LBGJ213512.73-010143
Smail, Ian; Swinbank, A. M.; Edge, A. C. +2 more
We model the mass distribution in the recently discovered Einstein ring LBGJ213512.73-010143 (the `Cosmic Eye') using archival Hubble Space Telescope imaging. We reconstruct the mass density profile of the z = 0.73 lens and the surface brightness distribution of the z = 3.07 source and find that the observed ring is best fitted with a dual-compone…