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Infrared mergers and infrared quasi-stellar objects with galactic winds - III. Mrk 231: an exploding young quasi-stellar object with composite outflow/broad absorption lines (and multiple expanding superbubbles)
Zheng, W.; Terlevich, R.; Lípari, S. +3 more
We present a study of outflow (OF) and broad absorption line (BAL) systems in Mrk 231, and in similar infrared (IR) quasi-stellar objects (QSOs). This study is based mainly on one-dimensional and two-dimensional spectroscopy (obtained at La Palma/William Herschel Telescope, Hubble Space Telescope, International Ultraviolet Explorer, European South…
Discovery and study of the accreting pulsar 2RXP J130159.6-635806
Revnivtsev, M.; Lutovinov, A.; Chernyakova, M. +1 more
We report on analysis of the poorly studied source 2RXP J130159.6-635806 at different epochs with ASCA, BeppoSAX, XMM-Newton and INTEGRAL. The source shows coherent X-ray pulsations at a period ~700 s with an average spin-up rate of about . A broad-band (1-60 keV) spectral analysis of 2RXP J130159.6-635806 based on almost simultaneous XMM-Newton a…
Periodic variability during the X-ray decline of 4U 1636-53
Charles, P. A.; Bird, A. J.; Cornelisse, R. +2 more
We report the onset of a large amplitude, statistically significant periodicity (~46 d) in the Rossi X-ray Timing Explorer/All Sky Monitor (RXTE/ASM) data of the prototype X-ray burster 4U 1636-53, the X-ray flux of which has been gradually declining over the last 4 yr. This behaviour is remarkably similar to that observed in the neutron star low …
From young massive star cluster to old globular: the LV-σ0 relationship as a diagnostic tool
de Grijs, Richard; Tadhunter, Clive N.; Wilkinson, Mark I.
We present a new analysis of the properties of the young massive star clusters (YMCs) forming profusely in intense starburst environments, which demonstrates that these objects are plausible progenitors of the old globular clusters (GCs) seen abundantly in the Local Group. The method is based on the tight relationship for old GCs between their V-b…
The fingerprint of binary intermediate-mass black holes in globular clusters: suprathermal stars and angular momentum alignment
Possenti, A.; Mapelli, M.; Sigurdsson, S. +1 more
We explore the signatures that a binary intermediate-mass black hole (IMBH) imprints on the velocity and on the angular momentum of globular cluster (GC) stars. Simulating three-body encounters between a star and a binary IMBH, we find that the binary IMBH generates a family of a few hundred stars (~100-300) which remain bound to the GC and have v…
X-rays from the Type II quasar in the hyperluminous infrared galaxy IRAS F15307+3252*
Iwasawa, K.; Fabian, A. C.; Crawford, C. S. +1 more
We report the detection of X-ray emission from the hyperluminous infrared galaxy IRAS F15307 + 3252 at z= 0.93 and its properties obtained from XMM-Newton observations. Although the X-ray emission is very faint and the data are noisy, a prominent line-like feature in the observed 3-4 keV range is inferred from both photometric and spectroscopic te…
A complete view of the broad-line radio galaxy 4C +74.26 with XMM-Newton
Ballantyne, D. R.
This paper presents a timing study and broad-band spectral analysis of the broad-line radio galaxy 4C +74.26 based on a 35-ks XMM-Newton observation. As found in previous data sets, the source exhibits no evidence for rapid variability, and its 0.2-10 keV light curve is well fitted by a constant. An excellent fit to the pn 0.3-12 keV spectrum was …
Determination of Cepheid parameters by light-curve template fitting
Berdnikov, L. N.; Tanvir, N. R.; Ngeow, C. C. +3 more
We describe techniques to characterize the light curves of regular variable stars by applying principal component analysis (PCA) to a training set of high-quality data, and to fit the resulting light-curve templates to sparse and noisy photometry to obtain parameters such as periods, mean magnitudes etc. The PCA approach allows us to efficiently r…
High-resolution observations of SN 2001gd in NGC 5033
Lundqvist, P.; Ros, E.; Guerrero, M. A. +8 more
We report on 8.4-GHz very-long-baseline interferometry (VLBI) observations of SN 2001gd in the spiral galaxy NGC 5033 made on 2002 June 26 (2002.48) and 2003 April 8 (2003.27). We used the interferometric visibility data to estimate angular diameter sizes for the supernova by model fitting. Our data nominally suggest a relatively strong decelerati…
The X-ray spectrum of NGC 7213 and the Seyfert-LINER connection
Page, M. J.; Branduardi-Raymont, G.; Soria, R. +3 more
We present an XMM-Newton observation of the Seyfert-LINER (low-ionization nuclear emission-line region) galaxy NGC 7213. The RGS soft X-ray spectrum is well fitted with a power law plus soft X-ray collisionally ionized thermal plasma (kT= 0.18+0.03-0.01 keV). We confirm the presence of FeI, FeXXV and FeXXVI Kα emission in the…