Search Publications
The two-component giant radio halo in the galaxy cluster Abell 2142
Brunetti, G.; Rossetti, M.; Shimwell, T. W. +9 more
Aims: We report on a spectral study at radio frequencies of the giant radio halo in A 2142 (z = 0.0909), which we performed to explore its nature and origin. The optical and X-ray properties of the cluster suggest that A 2142 is not a major merger and the presence of a giant radio halo is somewhat surprising.
Methods: We performed deep r…
Suzaku observations of the merging galaxy cluster Abell 2255: The northeast radio relic
Zhang, Y. -Y.; Kaastra, J. S.; Fukazawa, Y. +12 more
We present the results of deep 140 ks Suzaku X-ray observations of the north-east (NE) radio relic of the merging galaxy cluster Abell 2255. The temperature structure of Abell 2255 is measured out to 0.9 times the virial radius (1.9 Mpc) in the NE direction for the first time. The Suzaku temperature map of the central region suggests a complex tem…
Dust and gas in star-forming galaxies at z 3. Extending galaxy uniformity to 11.5 billion years
Daddi, E.; Elbaz, D.; Dickinson, M. +10 more
We present millimetre dust emission measurements of two Lyman-break galaxies at z 3 and construct for the first time fully sampled infrared spectral energy distributions (SEDs), from mid-IR to the Rayleigh-Jeans tail, of individually detected, unlensed, UV-selected, main sequence (MS) galaxies at z = 3. The SED modelling of the two sources confirm…
Population synthesis to constrain Galactic and stellar physics. I. Determining age and mass of thin-disc red-giant stars
Reylé, C.; Robin, A. C.; Lagarde, N. +1 more
Context. The cornerstone mission of the European Space Agency, Gaia, together with forthcoming complementary surveys (CoRoT, Kepler, K2, APOGEE, and Gaia-ESO), will revolutionize our understanding of the formation and history of our Galaxy, providing accurate stellar masses, radii, ages, distances, as well as chemical properties for a very large s…
A test of Gaia Data Release 1 parallaxes: implications for the local distance scale
Casertano, Stefano; Riess, Adam G.; Bucciarelli, Beatrice +1 more
Aims: We present a comparison of Gaia Data Release 1 (DR1) parallaxes with photometric parallaxes for a sample of 212 Galactic Cepheids at a median distance of 2 kpc, and explore their implications on the distance scale and the local value of the Hubble constant H0.
Methods: The Cepheid distances are estimated from a recent ca…
Gaia Data Release 1. The photometric data
Gilmore, G.; Harrison, D. L.; Evans, N. W. +91 more
Context. This paper presents an overview of the photometric data that are part of the first Gaia data release.
Aims: The principles of the processing and the main characteristics of the Gaia photometric data are presented.
Methods: The calibration strategy is outlined briefly and the main properties of the resulting photometry are presen…
New constraints on the average escape fraction of Lyman continuum radiation in z 4 galaxies from the VIMOS Ultra Deep Survey (VUDS)
Maccagni, D.; Schaerer, D.; Thomas, R. +20 more
Context. Determining the average fraction of Lyman continuum (LyC) photons escaping high redshift galaxies is essential for understanding how reionization proceeded in the z> 6 Universe.
Aims: We want to measure the LyC signal from a sample of sources in the Chandra Deep Field South (CDFS) and COSMOS fields for which ultra-deep VIMOS spect…
Properties of the cosmological filament between two clusters: A possible detection of a large-scale accretion shock by Suzaku
Kaastra, J. S.; Mernier, F.; Ishisaki, Y. +7 more
We report on the results of a Suzaku observation of the plasma in the filament located between the two massive clusters of galaxies, Abell 399 and Abell 401. Abell 399 (z = 0.0724) and Abell 401 (z = 0.0737) are expected to be in the initial phase of a cluster merger. In the region between the two clusters, we find a clear enhancement in the tempe…
Partial redistribution in 3D non-LTE radiative transfer in solar-atmosphere models
Leenaarts, Jorrit; Sukhorukov, Andrii V.
Context. Resonance spectral lines such as H I Ly α, Mg II H&K, and Ca II H&K that form in the solar chromosphere, are influenced by the effects of 3D radiative transfer as well as partial redistribution (PRD). So far no one has modeled these lines including both effects simultaneously owing to the high computing demands of existing algorit…
Molecular gas properties of a lensed star-forming galaxy at z 3.6: a case study
Kneib, J. -P.; Schaerer, D.; Rujopakarn, W. +12 more
We report on the galaxy MACSJ0032-arc at zCO = 3.6314 discovered during the Herschel Lensing snapshot Survey of massive galaxy clusters, and strongly lensed by the cluster MACS J0032.1+1808. The successful detections of its rest-frame ultraviolet (UV), optical, far-infrared (FIR), millimeter, and radio continua, and of its CO emission e…