Search Publications
The VMC survey - XXIII. Model fitting of light and radial velocity curves of Small Magellanic Cloud classical Cepheids
Clementini, G.; Ripepi, V.; Molinaro, R. +7 more
We present the results of the χ2 minimization model fitting technique applied to optical and near-infrared photometric and radial velocity data for a sample of nine fundamental and three first overtone classical Cepheids in the Small Magellanic Cloud (SMC). The near-infrared photometry (JK filters) was obtained by the European Southern …
Cosmic phylogeny: reconstructing the chemical history of the solar neighbourhood with an evolutionary tree
Jofré, Paula; Das, Payel; Foley, Robert +1 more
Using 17 chemical elements as a proxy for stellar DNA, we present a full phylogenetic study of stars in the solar neighbourhood. This entails applying a clustering technique that is widely used in molecular biology to construct an evolutionary tree from which three branches emerge. These are interpreted as stellar populations that separate in age …
Intrinsic AGN SED & black hole growth in the Palomar-Green quasars
Lani, Caterina; Lutz, Dieter; Netzer, Hagai
We present a new analysis of the Palomar-Green quasar sample based on Spitzer and Herschel observations. (I) Assuming polycyclic aromatic hydrocarbon (PAH)-based star formation luminosities (LSF) similar to Symeonidis et al. (S16), we find mean and median intrinsic active galactic nucleus (AGN) spectral energy distributions (SEDs). Thes…
Evidence against a supervoid causing the CMB Cold Spot
Kovács, András; Shanks, Tom; Bremer, Malcolm N. +5 more
We report the results of the 2dF-VST ATLAS Cold Spot galaxy redshift survey (2CSz) based on imaging from VST ATLAS and spectroscopy from 2dF AAOmega over the core of the CMB Cold Spot. We sparsely surveyed the inner 5° radius of the Cold Spot to a limit of IAB ≤ 19.2, sampling ∼7000 galaxies at z < 0.4. We have found voids at z = 0.1…
The selection function of the RAVE survey
Grebel, Eva K.; Steinmetz, Matthias; Bland-Hawthorn, Joss +23 more
We characterize the selection function of RAdial Velocity Experiment (RAVE) using 2 Micron All Sky Survey (2MASS) as our underlying population, which we assume represents all stars that could have potentially been observed. We evaluate the completeness fraction as a function of position, magnitude and colour in two ways: first, on a field-by-field…
The age of 47 Tuc from self-consistent isochrone fits to colour-magnitude diagrams and the eclipsing member V69
Grundahl, F.; Milone, A. P.; Bedin, L. R. +3 more
Our aim is to derive a self-consistent age, distance and composition for the globular cluster 47 Tucanae (47 Tuc; NGC104). First, we re-evaluate the reddening towards the cluster resulting in a nominal E(B - V) = 0.03 ± 0.01 as the best estimate. The Teff of the components of the eclipsing binary member V69 is found to be 5900 ± 72 K fr…
CMB signatures of metal-free star formation and Planck 2015 polarization data
Heinrich, Chen He; Miranda, Vinicius; Hu, Wayne +1 more
Standard analyses of the reionization history of the Universe from Planck cosmic microwave background (CMB) polarization measurements consider only the overall optical depth to electron scattering (τ), and further assume a step-like reionization history. However, the polarization data contain information beyond the overall optical depth, and the a…
Hierarchical star formation across the grand-design spiral NGC 1566
Gouliermis, Dimitrios A.; Grebel, Eva K.; Smith, Linda J. +19 more
We investigate how star formation is spatially organized in the grand-design spiral NGC 1566 from deep Hubble Space Telescope photometry with the Legacy ExtraGalactic UV Survey. Our contour-based clustering analysis reveals 890 distinct stellar conglomerations at various levels of significance. These star-forming complexes are organized in a hiera…
Probing cosmological isotropy with Planck Sunyaev-Zeldovich galaxy clusters
Bernui, A.; Ferreira, I. S.; Alcaniz, J. S. +1 more
We probe the statistical isotropy hypothesis of the large-scale structure with the second Planck Sunyaev-Zeldovich (PSZ2) galaxy clusters data set. Our analysis adopts a statistical-geometrical method that compares the two-point angular-correlation function of objects in antipodal patches of the sky. Given possible observational biases, such as th…
A high-resolution H I study towards the supernova remnant Puppis A and its environments
Reynoso, E. M.; Cichowolski, S.; Walsh, A. J.
We observed the supernova remnant Puppis A in the 21 cm line with the Australia Telescope Compact Array with the aim of determining the systemic velocity and, hence, the corresponding kinematic distance. For the compact, background sources in the field, we obtain absorption spectra by applying two methods: (a) subtracting profiles on- and off-sour…