Search Publications
Flux and composition of interstellar dust at Saturn from Cassini’s Cosmic Dust Analyzer
Kempf, S.; Postberg, F.; Srama, R. +12 more
Interstellar dust (ISD) is the condensed phase of the interstellar medium. In situ data from the Cosmic Dust Analyzer on board the Cassini spacecraft reveal that the Saturnian system is passed by ISD grains from our immediate interstellar neighborhood, the local interstellar cloud. We determine the mass distribution of 36 interstellar grains, thei…
Cosmological axion and neutrino mass constraints from Planck 2015 temperature and polarization data
Di Valentino, Eleonora; Melchiorri, Alessandro; Mena, Olga +3 more
Axions currently provide the most compelling solution to the strong CP problem. These particles may be copiously produced in the early universe, including via thermal processes. Therefore, relic axions constitute a hot dark matter component and their masses are strongly degenerate with those of the three active neutrinos, as they leave identical s…
First detection of a diamagnetic cavity at comet 67P/Churyumov-Gerasimenko
Altwegg, K.; Glassmeier, K. -H.; Nilsson, H. +16 more
Context. The Rosetta magnetometer RPC-MAG has been exploring the plasma environment of comet 67P/Churyumov-Gerasimenko since August 2014. The first months were dominated by low-frequency waves which evolved into more complex features. However, at the end of July 2015, close to perihelion, the magnetometer detected a region that did not contain any…
The extraordinary amount of substructure in the Hubble Frontier Fields cluster Abell 2744
Kneib, J. -P.; Egami, E.; Eckert, D. +21 more
We present a joint optical/X-ray analysis of the massive galaxy cluster Abell 2744 (z = 0.308). Our strong- and weak-lensing analysis within the central region of the cluster, I.e. at R < 1 Mpc from the brightest cluster galaxy, reveals eight substructures, including the main core. All of these dark matter haloes are detected with a significanc…
Measuring the dynamical state of Planck SZ-selected clusters: X-ray peak - BCG offset
Bersanelli, M.; Maino, D.; Rossetti, M. +6 more
We want to characterize the dynamical state of galaxy clusters detected with the Sunyaev-Zeldovich (SZ) effect by Planck and compare them with the dynamical state of clusters selected in X-rays survey. We analysed a representative subsample of the Planck SZ catalogue, containing the 132 clusters with the highest signal to noise ratio and character…
Gaia Data Release 1. Pre-processing and source list creation
Mora, A.; Boudreault, S.; Jordan, S. +104 more
Context. The first data release from the Gaia mission contains accurate positions and magnitudes for more than a billion sources, and proper motions and parallaxes for the majority of the 2.5 million Hipparcos and Tycho-2 stars.
Aims: We describe three essential elements of the initial data treatment leading to this catalogue: the image analy…
Young Stars and Ionized Nebulae in M83: Comparing Chemical Abundances at High Metallicity.
Bresolin, Fabio; Kudritzki, Rolf-Peter; Urbaneja, Miguel A. +3 more
We present spectra of 14 A-type supergiants in the metal-rich spiral galaxy M83. We derive stellar parameters and metallicities and measure a spectroscopic distance modulus µ =28.47+/- 0.10 (4.9 ± 0.2 Mpc), in agreement with other methods. We use the stellar characteristic metallicity of M83 and other systems to discuss a version of the gala…
A Hubble Space Telescope survey of the host galaxies of Superluminous Supernovae
Lyman, J. D.; Angus, C. R.; Fruchter, A. S. +4 more
We present Hubble Space Telescope (HST) Wide Field Camera 3 UV and near-IR (nIR) imaging of 21 Superluminous Supernovae (SLSNe) host galaxies, providing a sensitive probe of star formation and stellar mass within the hosts. Comparing the photometric and morphological properties of these host galaxies with those of core-collapse supernovae (CCSNe) …
First Results from the MADCASH Survey: A Faint Dwarf Galaxy Companion to the Low-mass Spiral Galaxy NGC 2403 at 3.2 Mpc
Bell, Eric F.; Forbes, Duncan A.; Romanowsky, Aaron J. +13 more
We report the discovery of the faintest known dwarf galaxy satellite of a Large Magellanic Cloud (LMC) stellar-mass host beyond the Local Group (LG), based on deep imaging with Subaru/Hyper Suprime-Cam. Magellanic Analog Dwarf Companions And Stellar Halos (MADCASH) J074238+652501-dw lies ∼35 kpc in projection from NGC 2403, a dwarf spiral galaxy a…
A spectroscopic survey of X-ray-selected AGNs in the northern XMM-XXL field
Georgakakis, A.; Salvato, M.; Buchner, J. +10 more
This paper presents a survey of X-ray-selected active galactic nuclei (AGNs) with optical spectroscopic follow-up in a ∼ 18 deg2 area of the equatorial XMM-XXL north field. A sample of 8445 point-like X-ray sources detected by XMM-Newton above a limiting flux of F_{0.5-10 keV} > 10^{-15} erg cm^{-2} s^{-1} was matched to optical (Slo…