Search Publications
Cross-correlation of Lyman α absorbers with gas-rich galaxies
Ryan-Weber, Emma V.
The HI Parkes all-sky survey (HIPASS) galaxy catalogue is cross-correlated with known low redshift, low column density (NHI < 1015cm-2) Lyman α (Lyα) absorbers from the literature. The redshift-space correlation is found to be similar in strength to HIPASS galaxy self-clustering (correlation length s0,ag
X-ray spectra of sources in the 13H XMM-Newton/Chandra deep field
McHardy, I.; Page, M. J.; Seymour, N. +8 more
We present the X-ray spectra of 86 optically identified sources in the 13H XMM-Newton/Chandra deep field which have >70 X-ray counts. The majority of these sources have 2-10keV fluxes between 10-15 and 5 × 10-14ergcm-2s-1. The sample consists of 50 broad-line active galactic nuclei (BLAGN),…
Chandra monitoring observations of the ultraluminous X-ray source NGC 5204 X-1
Warwick, R. S.; Roberts, T. P.; Ward, M. J. +2 more
We report the results of a two-month campaign conducted with the Chandra X-ray observatory to monitor the ultraluminous X-ray source (ULX) NGC 5204 X-1. This was composed of a 50-ks observation, followed by ten 5-ks follow-ups spaced initially at ~3, then at ~10-d intervals. The ULX flux is seen to vary by factors ~5 on time-scales of a few days, …
INTEGRAL and XMM-Newton observations of the X-ray pulsar IGR J16320-4751/AX J1631.9-4752
Petrucci, P. -O.; Tomsick, J. A.; Rodriguez, J. +16 more
We report on observations of the X-ray pulsar IGR J16320-4751 (also known as AX J1631.9-4752) performed simultaneously with International Gamma-Ray Astrophysics Laboratory (INTEGRAL) and XMM-Newton. We refine the source position and identify the most likely infrared counterpart. Our simultaneous coverage allows us to confirm the presence of X-ray …
Mapping stellar kinematics across the Galactic bar: HST measurements of proper motions in 35 fields
Kozłowski, S.; Mao, S.; Wyrzykowski, Ł. +4 more
We present a proper motion mini-survey of 35 fields in the vicinity of Baade window, (l, b) = (1°, -4°), sampling roughly a 5 × 2.5-deg2 region of the Galactic bar. Our second epoch observations collected with the Advanced Camera for Surveys/High Resolution Channel instrument onboard the Hubble Space Telescope were combined with the arc…
Gemini/GMOS spectra of globular clusters in the Virgo giant elliptical NGC 4649
Forbes, Duncan A.; Beasley, Michael A.; Zepf, Stephen E. +8 more
NGC 4649 (M60) is one of a handful of giant Virgo ellipticals. We have obtained Gemini/GMOS (Gemini North Multi-Object Spectrograph) spectra for 38 globular clusters (GCs) associated with this galaxy. Applying the multi-index χ2 minimization technique of Proctor and Sansom with the single stellar population models of Thomas, Maraston an…
SCUBA observations of the Horsehead nebula - what did the horse swallow?
Bontemps, S.; Ward-Thompson, D.; Nutter, D. +2 more
We present observations taken with the Submillimetre Common-User Bolometer Array (SCUBA) on the James Clerk Maxwell Telescope (JCMT) of the Horsehead nebula in Orion (B33), at wavelengths of 450 and 850 µm. We see bright emission from that part of the cloud associated with the photon-dominated region (PDR) at the `top' of the horse's head, w…
Automated analysis of eclipsing binary light curves - II. Statistical analysis of OGLE LMC eclipsing binaries
Mazeh, T.; North, P.; Tamuz, O.
In the first paper of this series, we presented EBAS - Eclipsing Binary Automated Solver, a new fully automated algorithm to analyse the light curves of eclipsing binaries, based on the EBOP code. Here, we apply the new algorithm to the whole sample of 2580 binaries found in the Optical Gravitational Lensing Experiment (OGLE) Large Magellanic Clou…
Multiwavelength XMM-Newton observations of the Laor et al. sample of PG quasars
Schady, P.; Mason, K. O.; Starling, R. L. C. +3 more
We present XMM-Newton/EPIC spectra for the Laor et al. sample of Palomar Green (PG) quasars. We find that a power law provides a reasonable fit to the 2-5 keV region of the spectra. Excess soft X-ray emission below 2 keV is present for all objects, with the exception of those known to contain a warm absorber. However, a single power law is a poor …
The Tully-Fisher relation of intermediate redshift field and cluster galaxies from Subaru spectroscopy
Milvang-Jensen, B.; Aragón-Salamanca, A.; Bamford, S. P. +3 more
We have carried out spectroscopic observations in four cluster fields using Subaru's FOCAS multislit spectrograph and obtained spectra for 103 bright disc field and cluster galaxies at 0.06 <=z<= 1.20. 77 of these show emission lines, and 33 provide reasonably secure determinations of the galaxies' rotation velocity. The rotation velocities,…