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Absolute dimensions and apsidal motion of the eccentric binary PT Velorum
Demircan, O.; Bakış, V.; Eker, Z. +1 more
High-resolution (λ/dλ ~ 41000) echelle spectra of the eccentric binary system PT Vel were analysed. Precise spectroscopic orbital elements of the system were obtained by means of cross-correlation technique. According to the solution of radial velocities with Hipparcos and All Sky Automated Survey-3 (ASAS-3) light curves, PT Vel consists of two ma…
3C40 in Abell194: can tail radio galaxies exist in a quiescent cluster?
Hardcastle, M. J.; Sakelliou, Irini; Jetha, N. N.
The nearby cluster Abell194 hosts two luminous, distorted radio galaxies. Both reside within the cluster's core region, being separated in projection by only 100 kpc. It is often suggested that tailed radio galaxies such as these reside in clusters that are under formation and are accreting new material from their outskirts. In this paper, we stud…
Spectroscopic and photometric observations of the selected Algol-type binaries - II. V2080 Cygni and V2365 Ophiuchi
Frasca, A.; Çakırlı, Ö.; Sipahi, E. +9 more
This paper is the second in the planned series of investigations. We present new radial velocities and photometric observations of V2080 Cyg and V2365 Oph. New UBV photometric data and radial velocities were analysed for the systems' parameters. While V2080 Cyg consists of two nearly equal F-type main-sequence stars, V2365 Oph has two different co…
The iron abundance of the Magellanic Bridge
Dufton, P. L.; Thompson, H. M. A.; Ryans, R. S. I. +1 more
High-resolution Hubble Space Telescope ultraviolet spectra for five B-type stars in the Magellanic Bridge and in the Large (LMC) and Small (SMC) Magellanic Clouds have been analysed to estimate their iron abundances. Those for the Clouds are lower than estimates obtained from late-type stars or the optical lines in B-type stars by approximately 0.…
Physical parameters for Orion KL from modelling its ISO high-resolution far-IR CO line spectrum
White, G. J.; Barlow, M. J.; Cernicharo, J. +5 more
As part of the first high-resolution far-infrared (far-IR) spectral survey of the Orion Kleinmann-Low (KL) region, we observed 20 CO emission lines with Jup = 16 to 39 (upper levels from ~752 to 4294 K above the ground state). Observations were taken using the Long Wavelength Spectrometer on board the Infrared Space Observatory (ISO), i…
Correlated spectral variability in brown dwarfs
Bailer-Jones, C. A. L.
Models of brown dwarf atmospheres suggest they exhibit complex physical behaviour. Observations have shown that they are indeed dynamic, displaying small photometric variations over time-scales of hours. Here, I report results of infrared (0.95-1.64 µm) spectrophotometric monitoring of four field L and T dwarfs spanning time-scales of 0.1-5.…
Near ultraviolet-infrared colours of red-sequence galaxies in local clusters
Hudson, Michael J.; Lucey, John R.; Smith, Russell J. +2 more
We present GALEX near-ultraviolet (NUV) and Two-Micron All-Sky Survey J-band photometry for red-sequence galaxies in local clusters. We define quiescent samples according to a strict emission threshold, removing galaxies with very recent star formation. We analyse the NUV-J colour-magnitude relation (CMR) and find that the intrinsic scatter is an …
Unlensing HST observations of the Einstein ring 1RXS J1131-1231: a Bayesian analysis
Brewer, B. J.; Lewis, G. F.
We present a source and lens reconstruction for the optical Einstein ring gravitational lens system RXS J1131-1231. We resolve detail in the source, which is the host galaxy of a z = 0.658 quasar, down to a resolution of 0.045 arcsec (this is the size of the smallest conclusively resolved structures, rather than the pixel scale), using a Bayesian …
Detection of blueshifted emission and absorption and a relativistic iron line in the X-ray spectrum of ESO323-G077
Bianchi, S.; Schartel, N.; Santos-Lleó, M. +4 more
We report on the X-ray observation of the Seyfert 1 galaxy ESO323-G077 performed with XMM-Newton. The EPIC spectra show a complex spectrum with conspicuous absorption and emission features. The continuum emission can be modelled with a power law with an index of 1.99 +/- 0.02 in the whole XMM-Newton energy band, marginally consistent with typical …
Fourier-resolved energy spectra of the Narrow-Line Seyfert 1 Mkn 766
Papadakis, I. E.; Turner, T. J.; Arévalo, P. +4 more
We compute Fourier-resolved X-ray spectra of the Seyfert 1 Markarian 766 to study the shape of the variable components contributing to the 0.3-10 keV energy spectrum and their time-scale dependence. The fractional variability spectra peak at 1-3 keV, as in other Seyfert 1 galaxies, consistent with either a constant contribution from a soft excess …