Search Publications

Variations in cometary dust composition from Giotto to Rosetta, clues to their formation mechanisms

Langevin, Yves; Fischer, Henning; Briois, Christelle +18 more

This paper reviews the current knowledge on the composition of cometary dust (ice, minerals and organics) in order to constrain their origin and formation mechanisms. Comets have been investigated by astronomical observations, space missions (Giotto to Rosetta), and by the analysis of cometary dust particles collected on Earth, chondritic porous i…

Ultramassive dense early-type galaxies: Velocity dispersions and number density evolution since z = 1.6

Gargiulo, A.; Saracco, P.; Tamburri, S. +2 more

Aims: We investigate the stellar mass assembly history of ultramassive (M_⋆ ≳ 10¹¹M_⊙) dense (Σ = M_⋆/2πR_e²> 2500M_⊙ pc^-2) early-type galaxies (ETGs, elliptical and spheroidal galaxies) selected on basis of visual classification over the last 9 Gyr.
Me…

A Search for Hyperluminous X-Ray Sources in the XMM-Newton Source Catalog

Bachetti, M.; Godet, O.; Webb, N. A. +2 more

We present a new method to identify luminous off-nuclear X-ray sources in the outskirts of galaxies from large public redshift surveys, distinguishing them from foreground and background interlopers. Using the 3XMM-DR5 catalog of X-ray sources and the SDSS DR12 spectroscopic sample of galaxies, with the help of this off-nuclear cross-matching tech…

Chandra X-Ray and Hubble Space Telescope Imaging of Optically Selected Kiloparsec-scale Binary Active Galactic Nuclei. II. Host Galaxy Morphology and AGN Activity

Shen, Yue; Ho, Luis C.; Strauss, Michael A. +4 more

Binary active galactic nuclei (AGNs) provide clues to how gas-rich mergers trigger and fuel AGNs and how supermassive black hole (SMBH) pairs evolve in a gas-rich environment. While significant effort has been invested in their identification, the detailed properties of binary AGNs and their host galaxies are still poorly constrained. In a compani…

Systematic or signal? How dark matter misalignments can bias strong lensing models of galaxy clusters

Kneib, J. P.; Jauzac, M.; Harvey, D.

We explore how assuming that mass traces light in strong gravitational lensing models can lead to systematic errors in the predicted position of multiple images. Using a model based on the galaxy cluster MACS J0416 (z = 0.397) from the Hubble Frontier Fields, we split each galactic halo into a baryonic and dark matter component. We then shift the …

Improved algorithm for the transmittance estimation of spectra obtained with SOIR/Venus Express

Bertaux, Jean-Loup; Vandaele, Ann Carine; Ristic, Bojan +5 more

Controlling Influence of Magnetic Field on Solar Wind Outflow: An Investigation using Current Sheet Source Surface Model

Poduval, B.

This Letter presents the results of an investigation into the controlling influence of large-scale magnetic field of the Sun in determining the solar wind outflow using two magnetostatic coronal models: current sheet source surface (CSSS) and potential field source surface. For this, we made use of the Wang and Sheeley inverse correlation between …

Resolving the Fan-spine Reconnection Geometry of a Small-scale Chromospheric Jet Event with the New Solar Telescope

Chen, Bin; Cao, Wenda; Goode, Philip R. +2 more

Jets are ubiquitously present in both quiet and active regions on the Sun. They are widely believed to be driven by magnetic reconnection. A fan-spine structure has been frequently reported in some coronal jets and flares, and has been regarded as a signature of ongoing magnetic reconnection in a topology consisting of a magnetic null connected by…

SOAR Optical and Near-infrared Spectroscopic Survey of Newly Discovered Massive Stars in the Periphery of Galactic Massive Star Clusters I-NGC 3603

Roman-Lopes, A.; Sanmartim, D.; Franco, G. A. P.

In this work, we present the results of a spectroscopic study of very massive stars (VMSs) found outside the center of the massive stellar cluster NGC 3603. From the analysis of the associated Southern Astrophysical Research (SOAR) Telescope spectroscopic data and related optical-near-IR (NIR) photometry, we confirm the existence of several VMSs i…

3C 279 in Outburst in 2015 June: A Broadband SED Study Based on the INTEGRAL Detection

Pian, Elena; Böttcher, Markus; Bottacini, Eugenio +1 more

Blazars radiate from radio through gamma-ray frequencies and thereby make ideal targets for multifrequency studies. Such studies allow the properties of the emitting jet to be constrained. 3C 279 is among the most notable blazars and therefore subject to extensive multifrequency campaigns. We report the results of a campaign ranging from near-IR t…