Search Publications
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…
Ultraviolet C II and Si III Transit Spectroscopy and Modeling of the Evaporating Atmosphere of GJ436b
Loyd, R. O. Parke; Redfield, Seth; France, Kevin +2 more
Hydrogen gas evaporating from the atmosphere of the hot-Neptune GJ436b absorbs over 50% of the stellar Lyα emission during transit. Given the planet’s atmospheric composition and energy-limited escape rate, this hydrogen outflow is expected to entrain heavier atoms such as C and O. We searched for C and Si in the escaping atmosphere of GJ436b usin…
The ISLAnds Project. III. Variable Stars in Six Andromeda Dwarf Spheroidal Galaxies
McQuinn, Kristen B. W.; Dolphin, Andrew E.; Skillman, Evan D. +15 more
We present a census of variable stars in six M31 dwarf spheroidal satellites observed with the Hubble Space Telescope. We detect 870 RR Lyrae (RRL) stars in the fields of And I (296), II (251), III (111), XV (117), XVI (8), and XXVIII (87). We also detect a total of 15 Anomalous Cepheids, three eclipsing binaries, and seven field RRL stars compati…
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…
Inflation model selection meets dark radiation
Tram, Thomas; Vennin, Vincent; Vallance, Robert
We investigate how inflation model selection is affected by the presence of additional free-streaming relativistic degrees of freedom, i.e. dark radiation. We perform a full Bayesian analysis of both inflation parameters and cosmological parameters taking reheating into account self-consistently. We compute the Bayesian evidence for a few represen…
MC2: Multiwavelength and Dynamical Analysis of the Merging Galaxy Cluster ZwCl 0008.8+5215: An Older and Less Massive Bullet Cluster
Dawson, William A.; Jee, M. James; van Weeren, Reinout J. +2 more
We present and analyze a rich data set including Subaru/SuprimeCam, HST/Advanced Camera for Surveys and Wide Field Camera 3, Keck/DEIMOS, Chandra/ACIS-I, and JVLA/C and D array for the merging cluster of galaxies ZwCl 0008.8+5215. With a joint Subaru+HST weak gravitational lensing analysis, we identify two dominant subclusters and estimate the mas…
Constraining the ΛCDM and Galileon models with recent cosmological data
Möller, A.; Astier, P.; Guy, J. +4 more
Aims: The Galileon theory belongs to the class of modified gravity models that can explain the late-time accelerated expansion of the Universe. In previous works, cosmological constraints on the Galileon model were derived, both in the uncoupled case and with a disformal coupling of the Galileon field to matter. There, we showed that these mo…
IRIS Burst Spectra Co-spatial to a Quiet-Sun Ellerman-like Brightening
Erdélyi, R.; Mathioudakis, M.; Oliver, R. +3 more
Ellerman bombs (EBs) have been widely studied over the past two decades; however, only recently have the counterparts of these events been observed in the quiet-Sun. The aim of this article is to further understand small-scale quiet-Sun Ellerman-like brightenings (QSEBs) through research into their spectral signatures, including investigating whet…
Polarimetry at millimeter wavelengths with the NIKA camera: calibration and performance
Adam, R.; Benoît, A.; Catalano, A. +37 more
Magnetic fields, which play a major role in a large number of astrophysical processes can be traced via observations of dust polarization. In particular, Planck low-resolution observations of dust polarization have demonstrated that Galactic filamentary structures, where star formation takes place, are associated to well organized magnetic fields.…