Search Publications
AGN spectral states from simultaneous UV and X-ray observations by XMM-Newton
Merloni, A.; Guainazzi, M.; Svoboda, J.
Context. It is generally believed that the supermassive black holes in active galactic nuclei (AGN) and stellar-mass black holes in X-ray binaries (XRBs) work in a similar way.
Aims: While XRBs evolve rapidly and several sources have undergone a few complete cycles from quiescence to an outburst and back, most AGN remain in the same state ove…
The First Scattered-light Image of the Debris Disk around the Sco-Cen Target HD 129590
Hinkley, Sasha; Matthews, Elisabeth; Stapelfeldt, Karl +7 more
We present the first scattered-light image of the debris disk around HD 129590, a ∼1.3 M ⊙ G1V member of the Scorpius-Centaurus association with an age of ∼10-16 Myr. The debris disk is imaged with the high contrast imaging instrument SPHERE at the Very Large Telescope, and is revealed by both the IRDIS and IFS subsytems, operating in t…
Distance biases in the estimation of the physical properties of Hi-GAL compact sources - I. Clump properties and the identification of high-mass star-forming candidates
Benedettini, M.; Elia, D.; Pezzuto, S. +8 more
The degradation of spatial resolution in star-forming regions, observed at large distances (d ≳ 1 kpc) with Herschel, can lead to estimates of the physical parameters of the detected compact sources (clumps), which do not necessarily mirror the properties of the original population of cores. This paper aims at quantifying the bias introduced in th…
The Highly Ionized Circumgalactic Medium is Kinematically Uniform around Galaxies
Charlton, Jane C.; Kacprzak, Glenn G.; Churchill, Christopher W. +3 more
The circumgalactic medium (CGM) traced by O VI λ λ 1031,1037 doublet absorption has been found to concentrate along the projected major and minor axes of the host galaxies. This suggests that O VI traces accreting and outflowing gas, respectively, which are key components of the baryon cycle of galaxies. We investigate this further by examining th…
Galaxy Merger Candidates in High-redshift Cluster Environments
Cooper, M. C.; Demarco, R.; Lidman, C. +14 more
We compile a sample of spectroscopically and photometrically selected cluster galaxies from four high-redshift galaxy clusters (1.59< z< 1.71) from the Spitzer Adaptation of the Red-Sequence Cluster Survey (SpARCS), and a comparison field sample selected from the UKIDSS Deep Survey. Using near-infrared imaging from the Hubble Space Telescope…
ZFIRE: The Evolution of the Stellar Mass Tully-Fisher Relation to Redshift ∼2.2
Kewley, Lisa J.; Kacprzak, Glenn G.; Glazebrook, Karl +8 more
Using observations made with MOSFIRE on Keck I as part of the ZFIRE survey, we present the stellar mass Tully-Fisher relation at 2.0< z< 2.5. The sample was drawn from a stellar-mass-limited, {K}s-band-selected catalog from ZFOURGE over the CANDELS area in the COSMOS field. We model the shear of the Hα emission line to derive rota…
Polarization and long-term variability of Sgr A* X-ray echo
Sunyaev, R.; Churazov, E.; Ponti, G. +1 more
We use a model of the molecular gas distribution within ∼100 pc from the centre of the Milky Way (Kruijssen, Dale & Longmore) to simulate time evolution and polarization properties of the reflected X-ray emission, associated with the past outbursts from Sgr A*. While this model is too simple to describe the complexity of the true gas distribut…
The ASTRODEEP Frontier Fields catalogues. III. Multiwavelength photometry and rest-frame properties of MACS-J0717 and MACS-J1149
Elbaz, D.; McLure, R. J.; Dunlop, J. S. +14 more
Aims: We present the multiwavelength photometry of two Frontier Fields massive galaxy clusters, MACS-J0717 and MACS-J1149, and their parallel fields, ranging from Hubble Space Telescope (HST) to ground-based K and Spitzer IRAC bands, and the public release of photometric redshifts and rest-frame properties of galaxies found in cluster and par…
Reformation of rippled quasi-parallel shocks: 2-D hybrid simulations
Wang, Shui; Huang, Can; Hao, Yufei +3 more
One-dimensional (1-D) hybrid simulations have demonstrated that a quasi-parallel shock is nonstationary and undergoes a reformation process. Recently, two-dimensional (2-D) hybrid simulations have revealed that ripples along the shock front is an inherent property of a quasi-parallel shock. In this paper, we investigate reformation process of a ri…
Binaries among low-mass stars in nearby young moving groups
Henning, Thomas; Brandner, Wolfgang; Schlieder, Joshua +5 more
The solar galactic neighborhood contains a number of young co-moving associations of stars (known as young moving groups) with ages of 10-150 Myr, which are prime targets for a range of scientific studies, including direct imaging planet searches. The late-type stellar populations of such groups still remain in their pre-main sequence phase, and a…