Search Publications
The local standard of rest from data on young objects with account for the Galactic spiral density wave
Bobylev, V. V.; Bajkova, A. T.
To estimate the peculiar velocity of the Sun with respect to the local standard of rest (LSR), we used young objects in the Solar neighbourhood with distance measurement errors within 10-15 per cent. These objects were the nearest Hipparcos stars of spectral classes O-B2.5, masers with trigonometric parallaxes measured by means of very long baseli…
No shock across part of a radio relic in the merging galaxy cluster ZwCl 2341.1+0000?
Simionescu, A.; van Weeren, R. J.; Brüggen, M. +2 more
The galaxy cluster ZwCl 2341.1+0000 is a merging system at z = 0.27, which hosts two radio relics and a central, faint, filamentary radio structure. The two radio relics have unusually flat integrated spectral indices of -0.49 ± 0.18 and -0.76 ± 0.17, values that cannot be easily reconciled with the theory of standard diffusive shock acceleration …
Iron-line and continuum variations in the XMM-Newton and Suzaku spectra of the neutron-star low-mass X-ray binary 4U 1636-53
Homan, Jeroen; Hiemstra, Beike; Belloni, Tomaso +3 more
We used six simultaneous XMM-Newton and Rossi X-ray Timing Explorer plus five Suzaku observations to study the continuum spectrum and the iron emission line in the neutron-star low-mass X-ray binary 4U 1636-53. We modelled the spectra with two thermal components (representing the accretion disc and boundary layer), a Comptonized component (represe…
Dark matter-baryons separation at the lowest mass scale: the Bullet Group{star}.
Rossetti, M.; Gastaldello, F.; Ghizzardi, S. +13 more
We report on the X-ray observation of a strong lensing selected group, SL2S J08544-0121, with a total mass of 2.4 ± 0.6 × 1014 M⊙ which revealed a separation of 124 ± 20 kpc between the X-ray emitting collisional gas and the collisionless galaxies and dark matter (DM), traced by strong lensing. This source allows to put an or…
Low-luminosity X-ray sources and the Galactic ridge X-ray emission
Warwick, R. S.
Using the XMM-Newton slew survey, we construct a hard-band selected sample of low-luminosity Galactic X-ray sources. Two source populations are represented, namely coronally active stars and binaries (ASBs) and cataclysmic variables (CVs), with X-ray luminosities collectively spanning the range 1028-34 erg s-1 (2-10 keV). We …
Do the spectral energy distributions of type 1 active galactic nuclei show diversity?
Stewart, G. C.; Scott, A. E.
We create broad-band spectral energy distributions (SEDs) of 761 type 1 active galactic nuclei (AGN). The Scott et al. sample, created by a cross-correlation of the optical Sloan Digital Sky Survey Data Release 5 quasar catalogue and the 2XMMi catalogue of serendipitous X-ray sources, is further matched with the Faint Images of the Radio Sky at Tw…
Signatures of warm carbon monoxide in protoplanetary discs observed with Herschel SPIRE
Ivison, R. J.; Olofsson, G.; Ménard, F. +9 more
Molecular gas constitutes the dominant mass component of protoplanetary discs. To date, these sources have not been studied comprehensively at the longest far-infrared and shortest submillimetre wavelengths. This paper presents Herschel SPIRE FTS spectroscopic observations towards 18 protoplanetary discs, covering the entire 450-1540 GHz (666-195 …
Evidence for two modes of black hole accretion in massive galaxies at z∼2
Ferguson, H. C.; Salvato, M.; Nandra, K. +18 more
We investigate the relationship between active galactic nucleus (AGN) activity and host galaxy properties using a sample of massive galaxies at z ∼ 2 in the Chandra Deep Field-South (CDFS). A sample of 268 galaxies with M* > 1010.5 M⊙ at 1.4 < z < 3 are selected from Hubble Space Telescope wide field camer…
The changing X-ray time lag in MCG-6-30-15
Fabian, A. C.; Miniutti, G.; Matt, G. +6 more
MCG-6-30-15 is one of the most observed narrow-line Seyfert 1 galaxies in the X-ray band. In this paper, we examine the X-ray time lags in this source using a total of 600 ks in observations (440 ks exposure) taken with the XMM-Newton telescope (300 ks in 2001 and 300 ks in 2013). Both the old and new observations show the usual hard lag that incr…
The nature of supernovae 2010O and 2010P in Arp 299 - I. Near-infrared and optical evolution
Kankare, E.; Herrero-Illana, R.; Alberdi, A. +10 more
We present near-infrared and optical photometry, plus optical spectroscopy of two stripped-envelope supernovae (SNe) 2010O and 2010P that exploded in two different components of an interacting luminous infrared galaxy Arp 299 within only a few days of one another. SN 2010O is found to be photometrically and spectroscopically similar to many normal…