Search Publications
Elemental abundances of Galactic bulge planetary nebulae from optical recombination lines
Wang, W.; Liu, X. -W.
Deep long-slit optical spectrophotometric observations are presented for 25 Galactic bulge planetary nebulae (GBPNe) and six Galactic disc planetary nebulae (GDPNe). The spectra, combined with archival ultraviolet (UV) spectra obtained with the International Ultraviolet Explorer and infrared spectra obtained with the Infrared Space Observatory, ha…
New scaling relations in cluster radio haloes and the re-acceleration model
Brunetti, G.; Setti, G.; Cassano, R. +2 more
In this paper we derive new expected scaling relations for clusters with giant radio haloes in the framework of the re-acceleration scenario in a simplified, but physically motivated, form, namely: radio power (PR) versus size of the radio emitting region (RH), and PR versus total cluster mass (MH) conta…
Central kiloparsec of Seyfert and inactive host galaxies: a comparison of two-dimensional stellar and gaseous kinematics
Emsellem, Eric; Nagar, Neil M.; Mundell, Carole G. +1 more
We investigate the properties of the two-dimensional distribution and kinematics of ionized gas and stars in the central kiloparsec of a matched sample of nearby active (Seyfert) and inactive galaxies, using the SAURON integral field unit on the William Herschel Telescope. The ionized gas distributions show a range of low-excitation regions, such …
The escape of Lyman photons from a young starburst: the case of Haro11†
Hayes, Matthew; Östlin, Göran; Leitherer, Claus +5 more
Lyman α (Lyα) is one of the dominant tools used to probe the star-forming galaxy population at high redshift (z). However, astrophysical interpretations of data drawn from Lyα alone hinge on the Lyα escape fraction which, due to the complex radiative transport, may vary greatly. Here, we map the Lyα emission from the local luminous blue compact ga…
SWSextantis stars: the dominant population of cataclysmic variables with orbital periods between 3 and 4h
Gänsicke, B. T.; Allende Prieto, C.; Hagen, H. -J. +15 more
We present time-series optical photometry of five new cataclysmic variables (CVs) identified by the Hamburg Quasar Survey (HQS). The deep eclipses observed in HS 0129+2933 (= TT Tri), HS 0220+0603 and HS 0455+8315 provided very accurate orbital periods of 3.35129827(65), 3.58098501(34) and 3.56937674(26) h, respectively. HS 0805+3822 shows grazing…
γ2 Velorum: orbital solution and fundamental parameter determination with SUSI
Tuthill, P. G.; Davis, J.; Tango, W. J. +1 more
The first complete orbital solution for the double-lined spectroscopic binary system γ2 Velorum, obtained from measurements with the Sydney University Stellar Interferometer (SUSI), is presented. This system contains the closest example of a Wolf-Rayet star and the promise of full characterization of the basic properties of this exotic …
Supernovae in the Subaru Deep Field: an initial sample and Type Ia rate out to redshift 1.6
Sharon, K.; Gal-Yam, A.; Filippenko, A. V. +12 more
Large samples of high-redshift supernovae (SNe) are potentially powerful probes of cosmic star formation, metal enrichment and SN physics. We present initial results from a new deep SN survey, based on re-imaging in the R, i', z' bands, of the 0.25 deg2 Subaru Deep Field (SDF), with the 8.2-m Subaru telescope and Suprime-Cam. In a singl…
The GLARE Survey - II. Faint z ~ 6 Lyα line emitters in the HUDF
Bunker, Andrew J.; Glazebrook, Karl; Abraham, Roberto G. +6 more
The galaxy population at z ~ 6 has been the subject of intense study in recent years, culminating in the Hubble Ultra Deep Field (HUDF) - the deepest imaging survey yet. A large number of high-redshift galaxy candidates have been identified within the HUDF, but until now analysis of their properties has been hampered by the difficulty of obtaining…
Modelling mid-Z element atmospheres for strongly magnetized neutron stars
Mori, Kaya; Ho, Wynn C. G.
We construct models for strongly magnetized neutron star atmospheres composed of mid-Z elements (carbon, oxygen and neon) with magnetic fields B = 1012-1013 G and effective temperatures Teff = (1 - 5) × 106 K; this is done by first addressing the physics relevant to strongly magnetized plasmas and calcul…
Towards an understanding of the Of?p star HD 191612: optical spectroscopy
Walborn, Nolan R.; Donati, J. -F.; Herrero, A. +17 more
We present extensive optical spectroscopy of the early-type magnetic star HD 191612 (O6.5f?pe-O8fp). The Balmer and He I lines show strongly variable emission which is highly reproducible on a well-determined 538-d period. He II absorptions and metal lines (including many selective emission lines but excluding He IIλ4686 Å emission) are essentiall…