Search Publications
Magnetic White Dwarfs in the Two Micron All Sky Survey: A Search for Candidate Binary Systems
Hoard, D. W.; Wachter, Stefanie; Howell, S. B. +2 more
Our understanding of the formation and evolution of magnetic cataclysmic variables from initially detached, post-common-envelope binary stars containing a magnetic white dwarf and a main-sequence star is currently poorly constrained, due to the lack of observational identification of the progenitor systems. Very few potential pre-cataclysmic varia…
The cool wake around 4C 34.16 as seen by XMM-Newton
Hardcastle, M. J.; Ponman, T. J.; Stevens, I. R. +3 more
We present XMM-Newton observations of the wake-radio galaxy system 4C 34.16, which shows a cool and dense wake trailing behind the host galaxy of 4C 34.16. A comparison with numerical simulations is enlightening, as they demonstrate that the wake is produced mainly by ram pressure stripping during the galactic motion through the surrounding cluste…
Evolution of the Dependence of Rest-Frame Color and Morphology Distribution on Stellar Mass for Galaxies in the Hubble Deep Field-North
Yamada, T.; Kajisawa, M.
Using very deep Subaru K'-band imaging and archival Hubble Space Telescope WFPC2/NICMOS data of the Hubble Deep Field-North, we investigate the evolution of the stellar mass, color, and morphology of galaxies to z~3. We mainly examine the rest-frame U-V color distribution of galaxies as a function of stellar mass. At 0.3<~z<~2, galaxies seem…
Discovery of CH and OH in the -513 km s-1 Ejecta of η Carinae
Gull, T. R.; Nielsen, K. E.; Bruhweiler, F. +3 more
The very massive star η Carinae (η Car) is enshrouded in an unusual complex of stellar ejecta, which is highly depleted in C and O and enriched in He and N. This circumstellar gas gives rise to distinct absorption components corresponding to at least 20 different velocities along the line of sight. The velocity component at -513 km s-1 …
Noise characteristics of full-disc helioseismic observations made by resonant scattering spectrometers
Chaplin, W. J.; Elsworth, Y.; Isaak, G. R. +3 more
Resonant scattering spectrometers (RSSs) have been used to make high-precision full-disc helioseismic observations since the 1970s. They are capable of very high-precision determinations of line-shift, meaning that they are used to obtain precise velocity measurements, and, for suitably configured RSSs, the disc-averaged longitudinal magnetic fiel…
XMM-Newton observations of the interacting galaxy pairs NGC 7771/0 and NGC 2342/1
Zezas, A.; Roberts, T. P.; Ward, M. J. +1 more
We present XMM-Newton X-ray observations of the interacting galaxy pairs NGC 7771/7770 and NGC 2342/2341. In NGC 7771, for the first time we are able to resolve the X-ray emission into a bright central source plus two bright (LX > 1040 erg s-1) ultraluminous X-ray sources (ULXs) located either end of the bar. In…
Supersolar N/C in the Narrow-Line Seyfert 1 Galaxy Markarian 1044
Pogge, Richard W.; Nicastro, Fabrizio; Mathur, Smita +2 more
Narrow-line Seyfert 1 galaxies (NLS1s) are known to have extreme values of a number of properties compared to active galactic nuclei (AGNs) as a class. In particular, previous emission-line studies have suggested that NLS1s are unusually metal-rich compared to broad-line AGNs of comparable luminosity. We present low- and medium-resolution spectros…
HST/NICMOS observations of a proto-brown dwarf candidate
Henning, T.; Apai, D.; Lemke, D. +3 more
We present deep HST/NICMOS observations peering through the outflow cavity of the protostellar candidate IRAS 04381+2540 in the Taurus Molecular Cloud-1. A young stellar object as central source, a jet and a very faint and close (0.6'') companion are identified. The primary and the companion have similar colours, consistent with strong reddening. …
Cluster electron observations of the separatrix layer during traveling compression regions
Balogh, A.; Fazakerley, A. N.; Owen, C. J. +2 more
We present Cluster 4-point observations of electrons during traveling compression regions (TCRs) on 19 September 2001. The electron and |B| signatures vary with distance from the plasma sheet, confirming that transient plasma sheet bulges propagate past Cluster. TCRs with |B| increases have either no electron signature, or unidirectional ~1 keV el…
Dissipation scales in the Earth's plasma sheet estimated from Cluster measurements
Balogh, A.; Nakamura, R.; Baumjohann, W. +5 more
In order to estimate the dissipation time-scale in magnetic turbulence in the plasma sheet a novel method is introduced for classification of velocity dependent patterns of two-point probability density functions' shapes near their maxima. For the first time, we provide evidence for Reynolds number (velocity) dependent widening of the inertial ran…