Search Publications
MUSE observations of the lensing cluster Abell 1689
Bina, D.; Pelló, R.; Richard, J. +14 more
Context. This paper presents the results obtained with the Multi Unit Spectroscopic Explorer (MUSE) for the core of the lensing cluster Abell 1689, as part of MUSE's commissioning at the ESO Very Large Telescope.
Aims: Integral-field observations with MUSE provide a unique view of the central 1 × 1 arcmin2 region at intermediate sp…
The Bullet cluster at its best: weighing stars, gas, and dark matter
Kneib, J. -P.; Jullo, E.; Richard, J. +4 more
Aims: We present a new strong lensing mass reconstruction of the Bullet cluster (1E 0657-56) at z = 0.296, based on WFC3 and ACS HST imaging and VLT/FORS2 spectroscopy. The strong lensing constraints underwent substantial revision compared to previously published analysis, there are now 14 (six new and eight previously known) multiply-imaged …
The mass of the black hole in RE J1034+396
Hryniewicz, K.; Życki, P. T.; Czerny, B. +7 more
Context. The black hole mass measurement in active galaxies is a challenge, particularly in sources where the reverberation method cannot be applied.
Aims: We aim to determine the black hole mass in a very special object, RE J1034+396, one of the two active galactic nuclei (AGN) with quasi-periodic oscillations detected in X-rays, and a singl…
A closer look at a coronal loop rooted in a sunspot umbra
Peter, H.; Chitta, L. P.; Young, P. R.
Context. Extreme UV (EUV) and X-ray loops in the solar corona connect regions of enhanced magnetic activity, but they are not usually rooted in the dark umbrae of sunspots because the strong magnetic field found there suppresses convection. This means that the Poynting flux of magnetic energy into the upper atmosphere is not significant within the…
Theoretical modelling of the AGN iron line vs. continuum time-lags in the lamp-post geometry
Papadakis, I. E.; Emmanoulopoulos, D.; Dovčiak, M. +4 more
Context. Theoretical modelling of time-lags between variations in the Fe Kα emission and the X-ray continuum might shed light on the physics and geometry of the X-ray emitting region in active galaxies (AGN) and X-ray binaries. We here present the results from a systematic analysis of time-lags between variations in two energy bands (5-7 vs. 2-4 k…
Controversial age spreads from the main sequence turn-off and red clump in intermediate-age clusters in the LMC
Cabrera-Ziri, I.; Bastian, N.; Kozhurina-Platais, V. +5 more
Most star clusters at an intermediate age (1-2 Gyr) in the Large and Small Magellanic Clouds show a puzzling feature in their color-magnitude diagrams (CMD) that is not in agreement with a simple stellar population. The main sequence turn-off of these clusters is much broader than expected from photometric uncertainties. One interpretation of this…
The atmosphere of comet 67P/Churyumov-Gerasimenko diagnosed by charge-exchanged solar wind alpha particles
Kallio, E.; Gunell, H.; Behar, E. +6 more
Context. The ESA/Rosetta mission has been orbiting comet 67P/Churyumov-Gerasimenko since August 2014, measuring its dayside plasma environment. The ion spectrometer onboard Rosetta has detected two ion populations, one energetic with a solar wind origin (H+, He2+, He+), the other at lower energies with a cometary o…
High-redshift supernova rates measured with the gravitational telescope A 1689
Dahle, H.; Lidman, C.; Amanullah, R. +12 more
Aims: We present a ground-based, near-infrared search for lensed supernovae behind the massive cluster Abell 1689 at z = 0.18, which is one of the most powerful gravitational telescopes that nature provides.
Methods: Our survey was based on multi-epoch J-band observations with the HAWK-I instrument on VLT, with supporting optical data fr…
Is there any evidence that ionized outflows quench star formation in type 1 quasars at z < 1?
Maiolino, R.; Marconi, A.; Brusa, M. +6 more
Aims: The aim of this paper is to test the basic model of negative active galactic nuclei (AGN) feedback. According to this model, once the central black hole accretes at the Eddington limit and reaches a certain critical mass, AGN driven outflows blow out gas, suppressing star formation in the host galaxy and self-regulating black hole growt…
The XXL Survey. VI. The 1000 brightest X-ray point sources
Chiappetti, L.; Paltani, S.; Lidman, C. +36 more
Context. X-ray extragalactic surveys are ideal laboratories for the study of the evolution and clustering of active galactic nuclei (AGN). Usually, a combination of deep and wide surveys is necessary to create a complete picture of the population. Deep X-ray surveys provide the faint population at high redshift, while wide surveys provide the rare…