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Orbital elements, masses and distance of λ Scorpii A and B determined with the Sydney University Stellar Interferometer and high-resolution spectroscopy
Uytterhoeven, K.; Aerts, C.; Tuthill, P. G. +7 more
The triple system HD158926 (λSco) has been observed interferometrically with the Sydney University Stellar Interferometer, and the elements of the wide orbit have been determined. These are significantly more accurate than the previous elements found spectroscopically. The inclination of the wide orbit is consistent with the inclination previously…
Optical spectroscopy of X-Mega targets in the Carina nebula - VI. FO15: a new O-type double-lined eclipsing binary
Barbá, R.; Morrell, N. I.; Niemela, V. S. +3 more
We report the discovery of a new O-type double-lined spectroscopic binary with a short orbital period of 1.4 d. We find the primary component of this binary, FO15, to have an approximate spectral type O5.5Vz, i.e. a zero-age main-sequence (ZAMS) star. The secondary appears to be of spectral type O9.5V. We have performed a numerical model fit to th…
The white dwarf in AE Aqr brakes harder
Mauche, Christopher W.
Taking advantage of the very precise de Jager et al. optical white dwarf orbit and spin ephemerides; ASCA, XMM-Newton and Chandra X-ray observations spread over 10yr and a cumulative 27-yr baseline, we have found that in recent years the white dwarf in AE Aqr is spinning down at a rate that is slightly faster than predicted by the de Jager et al. …
Supermassive black hole mass functions at intermediate redshifts from spheroid and AGN luminosity functions
Ueda, Yoshihiro; Tamura, Naoyuki; Ohta, Kouji
Redshift evolution of supermassive black hole mass functions (BHMFs) is investigated up to z~ 1. BHMFs at intermediate redshifts are calculated in two ways. One way is from early-type galaxy luminosity functions (LFs); we assume an MBH-Lsph correlation at a redshift by considering a passive evolution of Lsph in the…
Variability and multiperiodic oscillations in the X-ray light curve of the classical nova V4743 Sgr
Ness, J. -U.; Orio, M.; Gonzalez-Riestra, R. +5 more
The classical nova V4743 Sgr was observed with XMM-Newton for about 10h on 2003 April 4, 6.5 months after optical maximum. At this time, this nova had become the brightest supersoft X-ray source ever observed. In this paper, we present the results of a time-series analysis performed on the X-ray light curve (LC) obtained in this observation, and i…
The association between gas and galaxies - I. CFHT spectroscopy and pair analysis
Morris, Simon L.; Jannuzi, Buell T.
We investigate the relative distribution of the gaseous contents of the Universe (as traced by a sample of Lyα absorbers), and the luminous baryonic matter (as traced by a redshift survey of galaxies in the same volume searched for Lyα absorbers), along 16 lines of sight (LOS) between redshifts 0 and 1. Our galaxy redshift survey was made with the…
The X-ray properties of optically selected z > 0.6 clusters in the European Southern Observatory Distant Cluster Survey
Pelló, R.; Milvang-Jensen, B.; Halliday, C. +11 more
We present XMM-Newton observations of three optically selected z > 0.6 clusters from the European Southern Observatory (ESO) Distant Cluster Survey (EDisCS), comprising the first results of a planned X-ray survey of the full EDisCS high-redshift sample. The EDisCS clusters were identified in the Las Campanas Distant Cluster Survey as surface br…
XMM-Newton observations of the complex spin pulse of the intermediate polar PQ Geminorum
Hellier, Coel; Ramsay, Gavin; Evans, P. A.
The intermediate polar PQ Geminorum shows a complex pulsation, caused by a spinning white dwarf, which varies markedly with wavelength. We report XMM-Newton observations, including the soft and hard X-ray bands and the first ultraviolet light curves of this star. We update the ephemeris for PQ Gem allowing us to align these data with a compilation…
Have we detected the most luminous ULX so far?
Cappi, M.; Ponti, G.; Fabian, A. C. +4 more
We report the XMM-Newton detection of a moderately bright X-ray source (F0.5-7 ~ 8.2 × 10-14ergcm-2s-1) superimposed on the outer arms of the inactive spiral galaxy MCG-03-34-63 (z = 0.0213). It is clearly offset from the nucleus (by about 19 arcsec) but well within the D25 ellipse of the gala…
NGC 7419: a young open cluster with a number of very young intermediate mass pre-MS stars
Mathew, Blesson; Subramaniam, Annapurni; Ramya, S. +1 more
We present a photometric and spectroscopic study of the young open cluster NGC 7419, which is known to host a large number of classical Be stars for reasons not well understood. Based on CCD photometric observations of 327 stars in UBV passbands, we estimated the cluster parameters as, reddening [E(B - V)] = 1.65 +/- 0.15 mag and distance = 2900 +…