Polly Alexander

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We present high-resolution VLA observations at 8.4 GHz of the seventeen FRII radio galaxies with 0:15 < z < 0:30 and LAS < 190 arcsec from the sample of Laing, Riley & Longair (1983), together with 5-GHz MERLIN observations of one source. Jets have been discovered in 3C20, 4C14.11, 3C 234 and 3C436, and well imaged for the rst time in a number of other(More)
Den sites are critical resources that ultimately influence the population dynamics of many species. Little is known about cougar den selection, even though dens likely play important roles in cougar fitness and kitten survivorship. Thus, we aimed to describe cougar den site selection in the Southern Yellowstone Ecosystem (SYE) at two scales (third- and(More)
The propagation of underwater acoustic signals in polar regions is dominated by an upward refracting sound speed environment and the presence of a dynamic highly variable ice canopy. This paper provides an overview of the acoustic properties of sea ice and assesses the influence of ice canopy and water column properties on acoustic transmission loss for(More)
The nearby FRI radio source 3C 66B has been studied with the VLA at 1.5, 8 and 15 GHz with high resolution and sensitivity. The rst detailed maps of the counterjet are presented. Polarization maps in the jet and counterjet are shown; in each a resolved parallel-eld region surrounds a central core which changes from a parallel to a perpendicular eld(More)
We present Giant Metrewave Radio Telescope 21-cm HI observations towards a sample of compact radio sources behind galaxy groups, to search for cool HI. The results – from high dynamic range spectra for 8 lines-of-sight through 7 galaxy groups – do not show any evidence for absorption by cool HI. At a resolution of 20 km s −1 , the optical depth upper limits(More)
We present data probing the spatial and kinematical distribution of both the atomic (H I) and molecular (CO) gas in NGC 5218, the late-type barred spiral galaxy in the spiral–elliptical interacting pair, Arp 104. We consider these data in conjunction with far-infrared and radio continuum data, and N-body simulations, to study the galaxies interactions, and(More)
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