Search Publications
Non-circular motion evidence in the circumnuclear region of M100 (NGC 4321)
Battaner, E.; Mediavilla, E.; Castillo-Morales, A. +1 more
We analyse new integral-field spectroscopy of the inner region (central 2.5 kpc) of the spiral galaxy NGC 4321 to study the peculiar kinematics of this region. Fourier analysis of the velocity residuals obtained by subtracting an axisymmetric rotation model from the Hα velocity field indicates that the distortions are global features generated by …
Exploring the X-ray spectral variability of MCG-6-30-15 with XMM-Newton
Larsson, J.; Fabian, A. C.; Miniutti, G. +1 more
We present a study of the spectral variability of the Seyfert I galaxy MCG-6-30-15 based on the two long XMM-Newton observations from 2000 and 2001. The X-ray spectrum and variability properties of the 2001 data have previously been well described with a two-component model consisting of a variable power-law and a much less variable reflection com…
INTEGRAL observations of the Small Magellanic Cloud
Udalski, A.; Hill, A. B.; Coe, M. J. +10 more
The first INTEGRAL observations of the Small Magellanic Cloud (SMC) (carried out in 2003) are reported in which two sources are clearly detected. The first source, SMC X-1, shows a hard X-ray eclipse and measurements of its pulse period indicate a continuation of the long-term spin-up now covering approximately 30 years. The second source is likel…
The cluster galaxy luminosity function at z = 0.3: a recent origin for the faint-end upturn?
Harsono, D.; de Propris, R.
We derive deep luminosity functions (LFs) (to Mz = -15) for galaxies in Abell 1835 (z = 0.25) and AC 114 (z = 0.31), and compare these with the local z' LF for 69 clusters. The data show that the faint-end upturn, the excess of galaxies above a single Schechter function at Mz < -17, does not exist in the higher redshift cl…
Multiwavelength investigation of a near-solar metallicity sub-DLA at zabs = 1.3647 towards PKS0237-233
Petitjean, Patrick; Srianand, Raghunathan; Gupta, Neeraj
We searched for 21-cm absorption associated with the zabs = 1.3647 absorption system towards the gigahertz peaked-spectrum source PKS0237-233 using the Giant Metrewave Radio Telescope (GMRT). A high quality Ultraviolet and Visible Echelle Spectrograph (UVES) spectrum shows that CI and CI* are detected at this redshift together with CII*…
A low mass cluster of extremely red galaxies at z = 1.10 in the GOODS Southern Field
Rebolo, Rafael; Díaz-Sánchez, Anastasio; Pérez-Garrido, Antonio +1 more
We have studied the spatial clustering of high redshift (z > 1) extremely red objects (EROs) as a function of photometric redshift in the GOODS Southern Field using public data. A remarkable overdensity of extremely red galaxies (I - Ks > 4) is found at an average photometric redshift zphot = 1.10. Nine objects (six are…
INTEGRAL high-energy monitoring of the X-ray burster KS 1741-293
Ubertini, P.; Bazzano, A.; De Cesare, G. +4 more
KS 1741-293, discovered in 1989 by the X-ray camera TTM on the Kvant module of the Mir space station and identified as an X-ray burster, had not been detected in the hard X-ray band until the advent of the INTEGRAL observatory. Moreover, this source has recently been the object of scientific discussion, being also associated with a nearby extended…
Near-infrared polarimetry and modelling of the dusty young planetary nebula IRAS 19306+1407
Gledhill, T. M.; Lowe, K. T. E.
We present near-infrared polarimetric images of the dusty circumstellar envelope (CSE) of IRAS 19306+1407, acquired at the United Kingdom Infrared Telescope (UKIRT) using the UKIRT 1-5 µm Imager Spectrometer (UIST) in conjunction with the half-waveplate module IRPOL2. We present additional 450- and 850-µm photometry data obtained with …
Comparison of high- and low-state X-ray spectra in the type 1.5 quasi-stellar object 2MASS 0918+2117
Wilkes, B. J.; Pounds, K. A.
When observed by XMM-Newton in 2003, the type 1.5 quasi-stellar object 2MASS 0918+2117 was found to be in a low state, with an X-ray flux approximately four to five times fainter than during an earlier Chandra observation. The 2-6 keV spectrum was unusually hard (photon index Γ ~ 1.25), with evidence for a reflection-dominated continuum, while a s…
An unexpected outburst from A0535+262
Hill, A. B.; Bird, A. J.; Scaringi, S. +6 more
A0535+262 is a transient Be/X-ray binary system which was in a quiescent phase from 1994 to 2005. In this paper we report on the timing and spectral properties of the INTEGRAL detection of the source in 2003 October. The source is detected for ~6000 s in the 18-100 keV energy band at a luminosity of ~3.8 × 1035ergs-1 this is …