Search Publications
AGB variables and the Mira period-luminosity relation
Whitelock, Patricia A.; Feast, Michael W.; Van Leeuwen, Floor
Published data for large-amplitude asymptotic giant branch variables in the Large Magellanic Cloud (LMC) are re-analysed to establish the constants for an infrared (K) period-luminosity relation of the form MK=ρ[log P- 2.38]+δ. A slope of ρ=-3.51 ± 0.20 and a zero-point of δ=-7.15 ± 0.06 are found for oxygen-rich Miras (if a distance mo…
The broad-lined Type Ic supernova 2003jd
Pian, E.; Frontera, F.; Gal-Yam, A. +28 more
The results of a worldwide coordinated observational campaign on the broad-lined Type Ic supernova (SN Ic) 2003jd are presented. In total, 74 photometric data points and 26 spectra were collected using 11 different telescopes. SN 2003jd is one of the most luminous SN Ic ever observed. A comparison with other Type Ic supernovae (SNe Ic) confirms th…
The structures of distant galaxies - I. Galaxy structures and the merger rate to z ~ 3 in the Hubble Ultra-Deep Field
Conselice, Christopher J.; Rajgor, Sheena; Myers, Robert
This paper begins a series in which we examine the structures of distant galaxies to directly determine the history of their formation modes. We start this series by examining the structures of zF850LP < 27 galaxies in the Hubble Ultra-Deep Field (UDF), the deepest high-resolution optical image taken to date. We investigate a few bas…
On the star formation rate - brightest cluster relation: estimating the peak star formation rate in post-merger galaxies
Bastian, N.
We further the recent discussion on the relation between the star formation rate (SFR) of a galaxy and the luminosity of its brightest star cluster (SFR versus MbrightestV). We first show that the observed trend of SFR versus MbrightestV is due to the brightest cluster in a galaxy being preferentially yo…
M dwarfs: effective temperatures, radii and metallicities
Casagrande, Luca; Flynn, Chris; Bessell, Michael
We empirically determine effective temperatures and bolometric luminosities for a large sample of nearby M dwarfs, for which high accuracy optical and infrared photometry is available. We introduce a new technique which exploits the flux ratio in different bands as a proxy of both effective temperature and metallicity. Our temperature scale for la…
Black holes and core expansion in massive star clusters
Davies, M. B.; Mackey, A. D.; Wilkinson, M. I. +1 more
In this study we present the results from realistic N-body modelling of massive star clusters in the Magellanic Clouds. We have computed eight simulations with N ~ 105 particles; six of these were evolved for at least a Hubble time. The aim of this modelling is to examine in detail the possibility of large-scale core expansion in massiv…
A catalogue of multiplicity among bright stellar systems
Eggleton, P. P.; Tokovinin, A. A.
We consider the multiplicity of stellar systems with (combined) magnitude brighter than 6.00 in Hipparcos magnitudes. We identify 4559 such bright systems (including the Sun), and the frequencies of multiplicities 1, 2,..., 7 are found to be 2718, 1437, 285, 86, 20, 11 and 2. We discuss the uncertainties, which are substantial. We also consider th…
Chandra unveils a binary active galactic nucleus in Mrk 463
Guainazzi, Matteo; Bianchi, Stefano; Piconcelli, Enrico +2 more
We analyse Chandra, XMM-Newton and Hubble Space Telescope (HST) data of the double-nucleus Ultraluminous Infrared Galaxy (ULIRG), Mrk 463. The Chandra detection of two luminous (L2-10keV = 1.5 × 1043 and 3.8 × 1042 erg cm-2 s-1), unresolved nuclei in Mrk 463 indicates that this galaxy hosts a …
The fraction of second generation stars in globular clusters from the analysis of the horizontal branch
D'Antona, F.; Caloi, V.
The majority of globular clusters show chemical inhomogeneities in the composition of their stars, apparently due to a second stellar generation in which the forming gas is enriched by hot-CNO cycled material processed in stars belonging to a first stellar generation. Clearly this evidence prompts questions on the modalities of formation of globul…
Mapping of molecular gas inflow towards the Seyfert nucleus of NGC4051 using Gemini NIFS
Storchi-Bergmann, Thaisa; Riffel, Rogemar A.; Winge, Cláudia +3 more
We present 2D stellar and gaseous kinematics of the inner ~130×180 pc2 of the Narrow-Line Seyfert 1 galaxy NGC4051 at a sampling of 4.5pc, from near-infrared K-band spectroscopic observations obtained with the Gemini's Near-infrared Integral Field Spectrograph (NIFS) operating with the ALTAIR adaptive optics module. We have used the CO …