Search Publications
The most recent burst of star formation in the massive elliptical galaxy NGC 1052
Prieto, M. A.; Acosta-Pulido, J. A.; López-Sanjuan, C. +2 more
High spatial resolution near-infrared (NIR) images of the central 24 × 24 arcsec2 (∼2 × 2 kpc2) of the elliptical galaxy NGC 1052 reveal a total of 25 compact sources randomly distributed in the region. 15 of them exhibit Hα luminosities an order of magnitude above the estimate for an evolved population of extreme horizontal …
An extended XMM-Newton observation of the Seyfert galaxy NGC 4051 - II. Soft X-ray emission from a limb-brightened shell of post-shock gas
Vaughan, S.; Pounds, K. A.
An extended XMM-Newton observation of the Seyfert 1 galaxy NGC 4051 in 2009 revealed a complex absorption spectrum, with a wide range of outflow velocities and ionization states. The main velocity and ionization structure was interpreted in Paper I in terms of a decelerating, recombining flow resulting from the shocking of a still higher velocity …
Abundance profiles and cool cores in galaxy groups
Finoguenov, Alexis; Ponman, Trevor J.; Rasmussen, Jesper +2 more
Using data from the two-dimensional XMM-Newton Group Survey (2dXGS), we have examined the abundance profile properties of both cool core (CC) and non-cool core (NCC) galaxy groups. The 10 NCC systems in our sample represent a population which to date has been poorly studied in the group regime. Fitting the abundance profiles as a linear function o…
Spectral evolution and polarization of variable structures in the pulsar wind nebula of PSR B0540-69.3
Lundqvist, P.; Olofsson, G.; Shibanov, Yu. A. +4 more
We present high spatial resolution optical imaging and polarization observations of the PSR B0540-69.3 and its highly dynamical pulsar wind nebula (PWN) performed with Hubble Space Telescope, and compare them with X-ray data obtained with the Chandra X-ray Observatory. In particular, we have studied the bright region south-west of the pulsar where…
CoRoT 102699796, the first metal-poor Herbig Ae pulsator: a hybrid δ Sct-γ Dor variable?
Catala, C.; Ventura, P.; Ripepi, V. +7 more
We present the analysis of the time series observations of CoRoT 102699796 obtained by the Convection, Rotation and planetary Transits (CoRoT) satellite that show the presence of five independent oscillation frequencies in the range 3.6-5 c d-1. Using spectra acquired with FLAMES@VLT, we derive the following stellar parameters: spectral…
Emission sparks around M 81 and in some dwarf spheroidal galaxies
Makarova, Lidia; Kaisin, Serafim; Karachentsev, Igor +1 more
We use Hα images of three clumps of young stars situated between M 81 and NGC 3077 to estimate their star formation rate. Radial velocities of the clumps measured by us, as well as the velocity of the H II region in the dwarf spheroidal (dSph) galaxy KDG 61, are compatible with their location at the outskirts of a large rotating gaseous disc aroun…
SWIFT observations of the Arp 147 ring galaxy system
Salter, G.; Davies, R. L.; Thatte, N. +6 more
We present observations of Arp 147, a galaxy system comprising a collisionally created ring galaxy and an early-type galaxy, using the Oxford SWIFT integral field spectrograph (IFS) at the 200-inch Hale telescope. We derive spatially resolved kinematics from the IFS data and use these to study the interaction between the two galaxies. We find the …
Far-infrared luminosity function of local star-forming galaxies in the AKARI Deep Field-South
Goto, Tomotsugu; Clements, D. L.; Shirahata, Mai +8 more
We present a far-infrared galaxy luminosity function for the local universe. We have obtained 389 spectroscopic redshifts for galaxies observed at 90 µm in the AKARI Deep Field-South, using the AAOmega fibre spectrograph via optical identifications in the digitized sky survey and 4-m class optical imaging. For the luminosity function present…
[O II] emitters in the GOODS field at z∼ 1.85: a homogeneous measure of evolving star formation
Ryan-Weber, E. V.; McMahon, R. G.; Venemans, B. P. +2 more
We present the results of a deep, near-infrared, narrow-band imaging survey at a central wavelength of 1.062 µm (FWHM = 0.01 µm) in the GOODS-South field using the ESO VLT instrument, HAWK-I. The data are used to carry out the highest redshift search for [O II] λ3727 Å emission line galaxies to date. The images reach an emission line f…
Broad-band spectral analysis of Aql X-1
Dewangan, Gulab; Misra, Ranjeev; Raichur, Harsha
We present the results of a broad-band spectral study of the transient low-mass X-ray binary Aql X-1 observed by the Suzaku and Rossi X-ray Timing Explorer satellites. The source was observed during its 2007 outburst in the high/soft (Banana) state and in the low/hard (Extreme Island) state. Both the Banana state and the Extreme Island state spect…