Search Publications
Constraining the absolute orientation of η Carinae's binary orbit: a 3D dynamical model for the broad [Fe III] emission
Gull, T. R.; Madura, T. I.; Owocki, S. P. +3 more
We present a three-dimensional (3D) dynamical model for the broad [Fe III] emission observed in η Carinae using the Hubble Space Telescope/Space Telescope Imaging Spectrograph (STIS). This model is based on full 3D smoothed particle hydrodynamics simulations of η Car's binary colliding winds. Radiative transfer codes are used to generate synthetic…
A Statistical Study of Solar Electron Events over One Solar Cycle
Krucker, Säm; Lin, R. P.; Mason, Glenn M. +1 more
We survey the statistical properties of 1191 solar electron events observed by the WIND 3DP instrument from <1 keV to gsim300 keV for a solar cycle (1995 through 2005). After taking into account times of high background, the corrected occurrence frequency of solar electron events versus peak flux exhibits a power-law distribution over three ord…
Reconstructing the Near-infrared Background Fluctuations from Known Galaxy Populations Using Multiband Measurements of Luminosity Functions
Ricotti, Massimo; Kashlinsky, Alexander; Helgason, Kari
We model fluctuations in the cosmic infrared background (CIB) arising from known galaxy populations using 233 measured UV, optical, and near-IR luminosity functions (LFs) from a variety of surveys spanning a wide range of redshifts. We compare best-fit Schechter parameters across the literature and find clear indication of evolution with redshift.…
The Herschel Virgo Cluster Survey. X. The relationship between cold dust and molecular gas content in Virgo spirals
Bianchi, S.; Fritz, J.; Madden, S. C. +16 more
Aims: We examine whether dust mass can trace the total or molecular gas mass in late-type Virgo cluster galaxies, and how the environment affects the dust-to-gas ratio and the molecular fraction.
Methods: Using the far-infrared emission, as observed by the Herschel Virgo Cluster Survey (HeViCS), and the integrated HI 21-cm and CO J = 1-0…
Sunyaev-Zel'dovich clusters in Millennium gas simulations
Thomas, Peter A.; Kay, Scott T.; Liddle, Andrew R. +5 more
Large surveys using the Sunyaev-Zel'dovich (SZ) effect to find clusters of galaxies are now starting to yield large numbers of systems out to high redshift, many of which are new discoveries. In order to provide theoretical interpretation for the release of the full SZ cluster samples over the next few years, we have exploited the large-volume Mil…
Estimating turbulent velocities in the elliptical galaxies NGC 5044 and NGC 5813
Kaastra, J. S.; de Plaa, J.; Churazov, E. +5 more
Context. The interstellar and intra-cluster medium (ICM) in giant elliptical galaxies and clusters of galaxies is often assumed to be in hydrostatic equilibrium. Numerical simulations, however, show that about 5-30% of the pressure in a cluster is provided by turbulence induced by, for example, the central active galactic nucleus (AGN) and merger …
Radio and X-Ray Observations of SN 2006jd: Another Strongly Interacting Type IIn Supernova
Chandra, Poonam; Fransson, Claes; Chevalier, Roger A. +5 more
We report four years of radio and X-ray monitoring of the Type IIn supernova SN 2006jd at radio wavelengths with the Very Large Array, Giant Metrewave Radio Telescope, and Expanded Very Large Array; at X-ray wavelengths with Chandra, XMM-Newton, and Swift-XRT. We assume that the radio and X-ray emitting particles are produced by shock interaction …
Outer-disk Populations in NGC 7793: Evidence for Stellar Radial Migration
Holwerda, Benne W.; Radburn-Smith, David J.; de Jong, Roelof S. +8 more
We analyzed the radial surface brightness profile of the spiral galaxy NGC 7793 using HST/ACS images from the GHOSTS survey and a new HST/WFC3 image across the disk break. We used the photometry of resolved stars to select distinct populations covering a wide range of stellar ages. We found breaks in the radial profiles of all stellar populations …
The Herschel Virgo Cluster Survey - VIII. The Bright Galaxy Sample
Ciesla, L.; Bianchi, S.; Fritz, J. +20 more
We describe the Herschel Virgo Cluster Survey and the first data that cover the complete survey area (four 4 × 4 deg2 regions). We use these data to measure and compare the global far-infrared properties of 78 optically bright galaxies that are selected at 500 µm and detected in all five far-infrared bands. We show that our measur…
An Observed Link between Active Galactic Nuclei and Violent Disk Instabilities in High-redshift Galaxies
Dickinson, Mark; Daddi, Emanuele; Juneau, Stéphanie +7 more
We provide evidence for a correlation between the presence of giant clumps and the occurrence of active galactic nuclei (AGNs) in disk galaxies. Giant clumps of 108-109 M ⊙ arise from violent gravitational instability in gas-rich galaxies, and it has been proposed that this instability could feed supermassive black…