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YSO jets in the Galactic plane from UWISH2 - I. MHO catalogue for Serpens and Aquila
Froebrich, D.; Ioannidis, G.
Jets and outflows from young stellar objects (YSOs) are important signposts of currently ongoing star formation. In order to study these objects, we are conducting an unbiased survey along the Galactic plane in the 1-0 S(1) emission line of molecular hydrogen at 2.122 µm using the United Kingdom Infrared Telescope. In this paper, we are focu…
Accretion flow diagnostics with X-ray spectral timing: the hard state of SWIFT J1753.5-0127
Maccarone, T. J.; Uttley, P.; Cassatella, P.
Recent XMM-Newton studies of X-ray variability in the hard states of black hole X-ray binaries (BHXRBs) indicate that the variability is generated in the 'standard' optically thick accretion disc that is responsible for the multi-colour blackbody emission. The variability originates in the disc as mass-accretion fluctuations and propagates through…
The properties of the brightest Lyα emitters at z=5.7
Schaerer, D.; Meisenheimer, K.; Lidman, C. +5 more
We use deep Very Large Telescope (VLT) optical and near-infrared spectroscopy and deep Spitzer/IRAC imaging to examine the properties of two of the most luminous Lyα emitters at z= 5.7. The continuum redward of the Lyα line is clearly detected in both objects, thus facilitating a relatively accurate measurement (10-20 per cent uncertainties) of th…
Variable stars in the Cetus dwarf spheroidal galaxy: population gradients and connections with the star formation history
Stetson, P. B.; Bono, G.; Fiorentino, G. +7 more
We investigate the variable star content of the isolated, Local Group, dwarf spheroidal (dSph) galaxy Cetus. Multi-epoch, wide-field images collected with the Very Large Telescope/Visible Multiobject Spectrograph camera allowed us to detect 638 variable stars (630 RR Lyrae stars and eight anomalous Cepheids), 475 of which are new detections. We pr…
X-ray colour-colour selection for heavily absorbed active galactic nuclei
Nandra, Kirpal; Brightman, Murray
We present a method for the identification of heavily absorbed active galactic nuclei (AGN) (NH > 1023 cm-2) from X-ray photometric data. We do this using a set of XMM-Newton reference spectra of local galaxies for which we have accurate NH information, as described in Brightman & Nandra. The tech…
Residual cooling and persistent star formation amid active galactic nucleus feedback in Abell 2597
Fabian, A. C.; Combes, F.; Salomé, P. +18 more
New Chandra X-ray and Herschel Far-Infrared (FIR) observations enable a multiwavelength study of active galactic nucleus (AGN) heating and intracluster medium (ICM) cooling in the brightest cluster galaxy (BCG) of Abell 2597 (z= 0.0821). The new Chandra observations reveal the central ≲30 kpc X-ray cavity network to be more extensive than previous…
Evolution of the spectral curvature in the ultraluminous X-ray source Holmberg II X-1
Kaaret, P.; Farrell, S. A.; Poutanen, J. +2 more
Ultraluminous X-ray sources (ULXs) are interesting systems as they can host intermediate-mass black holes. Alternatively, ULXs can represent stellar mass black holes accreting at super-Eddington rates. Recently, spectral curvature or breaks at energies above a few keV have been detected in high-quality ULX spectra. These spectral features have bee…
The luminosity function and stellar mass-to-light ratio of the massive globular cluster NGC 2419
Dalessandro, E.; Bellazzini, M.; Ibata, R. +1 more
We used archival Hubble Space Telescope Wide Field Camera 3 (WFC3) images to obtain the luminosity function of the remote globular cluster NGC 2419 from 2 mag above the horizontal branch level down to ≃ 3.0 mag below the turn-off point (to MI≃ 6.4), approximately covering the range of initial stellar masses ?. The completeness-corrected…
HESS observations of the Carina nebula and its enigmatic colliding wind binary Eta Carinae
Klochkov, D.; Santangelo, A.; Quirrenbach, A. +191 more
The massive binary system Eta Carinae and the surrounding H II complex, the Carina nebula, are potential particle acceleration sites from which very high energy (VHE; E≥ 100 GeV) γ-ray emission could be expected. This paper presents data collected during VHE γ-ray observations with the HESS telescope array from 2004 to 2010, which cover a full orb…
New insights into the star formation histories of candidate intermediate-age early-type galaxies from K'-band imaging of globular clusters
Georgiev, Iskren Y.; Goudfrooij, Paul; Puzia, Thomas H.
We investigate the age and metallicity distributions of bright globular clusters (GCs) in the candidate intermediate-age early-type galaxies NGC 3610, 584 and 3377 using a combination of new Gemini's Near InfraRed Imager and Spectrometer K'-band imaging and existing optical VI photometry from Hubble Space Telescope data. The V-I versus I-K' colour…