Search Publications
A giant elliptical galaxy with a lightweight initial mass function
Lucey, John R.; Smith, Russell J.
We present new observations of the closest known strong-lensing galaxy, the σ ≈ 330 km s- 1 giant elliptical ESO325-G004, made with the ESO Very Large Telescope. The low redshift of the lens (zl = 0.035) results in arcs being formed at a small fraction of the effective radius (REin = 2.85 arcsec ≈ Reff/4…
The bright end of the exo-Zodi luminosity function: disc evolution and implications for exo-Earth detectability
Wyatt, M. C.; Kennedy, G. M.
We present the first characterisation of the 12 µm warm dust (`exo-Zodi') luminosity function around Sun-like stars, focusing on the dustiest systems that can be identified by the WISE mission. We use the sample of main-sequence stars observed by Hipparcos within 150 pc as an unbiased sample, and report the detection of six new warm dust can…
Red Giant Branch Bump Brightness and Number Counts in 72 Galactic Globular Clusters Observed with the Hubble Space Telescope
Udalski, Andrzej; Pinsonneault, Marc H.; Nataf, David M. +1 more
We present the broadest and most precise empirical investigation of red giant branch bump (RGBB) brightness and number counts ever conducted. We implement a new method and use data from two Hubble Space Telescope globular cluster (GC) surveys to measure the brightness and star counts of the RGBB in 72 GCs. The median measurement precision is 0.018…
An X-Ray View of the Jet Cycle in the Radio-loud AGN 3C120
Miller, Eric D.; Fabian, Andrew C.; Brenneman, Laura W. +10 more
We present a study of the central engine in the broad-line radio galaxy 3C120 using a multi-epoch analysis of a deep XMM-Newton observation and two deep Suzaku pointings (in 2012). In order to place our spectral data into the context of the disk-disruption/jet-ejection cycles displayed by this object, we monitor the source in the UV/X-ray bands, a…
The Impact of Starbursts on the Circumgalactic Medium
Heckman, Timothy; Wild, Vivienne; Borthakur, Sanchayeeta +2 more
We present a study exploring the impact of a starburst on the properties of the surrounding circumgalactic medium (CGM): gas located beyond the galaxy's stellar body and extending out to the virial radius (~200 kpc). We obtained ultraviolet spectroscopic data from the Cosmic Origins Spectrograph (COS) probing the CGM of 20 low-redshift foreground …
Relativistic electron microbursts due to nonlinear pitch angle scattering by EMIC triggered emissions
Omura, Yoshiharu; Zhao, Qinghua
We show that the anomalous cyclotron resonance between relativistic electrons and electromagnetic ion cyclotron (EMIC) triggered emissions takes place very effectively near the magnetic equator because of the variation of the ambient magnetic field. Efficient precipitations are caused by nonlinear trapping of relativistic electrons by electromagne…
Why circumstellar disks are so faint in scattered light: the case of HD 100546
Dominik, C.; Min, M.; Schneider, G. +2 more
Context. Scattered light images of circumstellar disks play an important role in characterizing the planet forming environments around young stars. The characteristic size of the scattering dust grains can be estimated from the observed brightness asymmetry between the near and far side of the disk, for example using standard Mie theory. Such mode…
The Extended GMRT Radio Halo Survey. I. New upper limits on radio halos and mini-halos
Brunetti, G.; Kale, R.; Giacintucci, S. +5 more
Context. A fraction of galaxy clusters host diffuse radio sources called radio halos, radio relics and mini-halos. These are associated with the relativistic electrons and magnetic fields present on ~Mpc scales in the intra-cluster medium.
Aims: We aim to carry out a systematic radio survey of all luminous galaxy clusters selected from the RE…
Formation of the compact jets in the black hole GX 339-4.
Aussel, H.; Tomsick, J. A.; Rodriguez, J. +15 more
Galactic black hole binaries produce powerful outflows which emit over almost the entire electromagnetic spectrum. Here, we report the first detection with the Herschel observatory of a variable far-infrared source associated with the compact jets of the black hole transient GX 339-4 during the decay of its recent 2010-2011 outburst, after the tra…
A Cosmic Microwave Background Lensing Mass Map and Its Correlation with the Cosmic Infrared Background
Bock, J.; Conley, A.; Bleem, L. E. +54 more
We use a temperature map of the cosmic microwave background (CMB) obtained using the South Pole Telescope at 150 GHz to construct a map of the gravitational convergence to z ~ 1100, revealing the fluctuations in the projected mass density. This map shows individual features that are significant at the ~4σ level, providing the first image of CMB le…