Search Publications
Modeling ULF waves in a compressed dipole magnetic field
Rae, I. J.; Rankin, R.; Degeling, A. W. +2 more
This paper presents the results of a linear model for global scale magneto-hydrodynamic (MHD) waves in a compressed dipole model magnetosphere. We examine scenarios where a localized monochromatic source along the magnetopause boundary launches MHD fast mode ultralow frequency (ULF) waves into the magnetosphere, where they couple to shear Alfvén w…
Scaling Laws and Temperature Profiles for Solar and Stellar Coronal Loops with Non-uniform Heating
Martens, P. C. H.
The bulk of solar coronal radiative loss consists of soft X-ray emission from quasi-static loops at the cores of active regions. In order to develop diagnostics for determining the heating mechanism of these loops from observations by coronal imaging instruments, I have developed analytical solutions for the temperature structure and scaling laws …
The kilohertz quasi-periodic oscillations during the Z and atoll phases of the unique transient XTE J1701-462
Homan, Jeroen; Belloni, Tomaso; Wijnands, Rudy +6 more
We analysed 866 observations of the neutron star low-mass X-ray binary XTE J1701-462 during its 2006-2007 outburst. XTE J1701-462 is the only example so far of a source that during an outburst showed, beyond any doubt, spectral and timing characteristics both of the Z and atoll type. There are 707 RXTE observations (~2.5 Ms) of the source in the Z…
Diamonds on the Hat: globular clusters in the Sombrero galaxy (M104)
Bailin, Jeremy; Spitler, Lee R.; Forbes, Duncan A. +1 more
Images from the Hubble Space Telescope Advanced Camera for surveys are used to carry out a new photometric study of the globular clusters (GCs) in M104, the Sombrero galaxy. The primary focus of our study is the characteristic distribution function of linear sizes [size distribution function (SDF)] of the GCs. We measure the effective radii for 65…
The Herschel Virgo Cluster Survey . VI. The far-infrared view of M 87
Böhringer, H.; Bomans, D. J.; Bianchi, S. +29 more
The origin of the far-infrared emission from the nearby radio galaxy M 87 remains a matter of debate. Some studies find evidence of a far-infrared excess due to thermal dust emission, whereas others propose that the far-infrared emission can be explained by synchrotron emission without the need for an additional dust emission component. We present…
Searching for the inverse-Compton emission from bright cluster-centre radio galaxies
Hardcastle, M. J.; Croston, J. H.
We use deep archival Chandra and XMM-Newton observations of three of the brightest cluster-centre radio galaxies in the sky, Cygnus A, Hercules A and Hydra A, to search for inverse-Compton emission from the population of electrons responsible for the low-frequency radio emission. Using simulated observations, we derive robust estimates for the unc…
Magnetic field dipolarization in the deep inner magnetosphere and its role in development of O+-rich ring current
Keika, K.; Koshiishi, H.; Matsumoto, H. +5 more
We studied magnetic field dipolarization and associated ion acceleration in the deep inner magnetosphere, using magnetic field data obtained by the magnetometer on board the Mission Demonstration Satellite 1 (MDS-1) and the energetic neutral atom (ENA) flux data obtained by the high-energy neutral analyzer imager on board the Imager for Magnetopau…
The Double-degenerate Nucleus of the Planetary Nebula TS 01: A Close Binary Evolution Showcase
Wilms, Jörn; Rauch, Thomas; Tomsick, John +8 more
We present a detailed investigation of SBS 1150+599A, a close binary star hosted by the planetary nebula PN G135.9+55.9 (TS 01). The nebula, located in the Galactic halo, is the most oxygen-poor known to date and is the only one known to harbor a double degenerate core. We present XMM-Newton observations of this object, which allowed the detection…
Herschel-PACS imaging of protostars in the HH 1-2 outflow complex
Maret, S.; Henning, T.; Manoj, P. +22 more
We present 70 and 160 µm Herschel science demonstration images of a field in the Orion A molecular cloud that contains the prototypical Herbig-Haro objects HH 1 and 2, obtained with the Photodetector Array Camera and Spectrometer (PACS). These observations demonstrate Herschel's unprecedented ability to study the rich population of protostar…
Long-term X-ray Changes in the Emission from the Anomalous X-ray Pulsar 4U 0142+61
Gonzalez, M. E.; Kaspi, V. M.; Woods, P. M. +3 more
We present results obtained from X-ray observations of the anomalous X-ray pulsar (AXP) 4U 0142+61 taken between 2000 and 2008 using XMM-Newton, Chandra, and Swift. These observations coincide with periods of long-term changes and burst epochs previously reported using the Rossi X-ray Timing Explorer (RXTE). In observations taken before 2006, we f…