5,110 research outputs found
For the Love of Men
The HSUS is concerned that sled-dog racing is gaining popularity and support. The society is committed to protecting the interests of animals and improving the quality of their lives, and sled-dog racing is an unnecessary and dangerous activity for people as well as animals.
In March, David K. Wills, HSUS vice president for investigations, went to Alaska to observe the Iditarod sled-dog race. The HSUS views the Iditarod, in theory and in practice, with increasing concern. We believe that unless the organizers of such spectacles eliminate the elements of risk to the animals, the events should be prohibited in their entirety. The challenge is to determine how such reforms or prohibitions are to be achieved
A Parsec-Scale Study of the 5/15 GHz Spectral Indices of the Compact Radio Sources in M82
Observations of the starburst galaxy, M82, have been made with the VLA in its
A-configuration at 15 GHz and MERLIN at 5 GHz enabling a spectral analysis of
the compact radio structure on a scale of < 0.1'' (1.6 pc). Crucial to these
observations was the inclusion of the Pie Town VLBA antenna, which increased
the resolution of the VLA observations by a factor of ~2. A number of the
weaker sources are shown to have thermal spectra and are identified as HII
regions with emission measures ~10^7 cm^-6 pc. Some of the sources appear to be
optically thick at 5 GHz implying even higher emission measures of ~10^8 cm^-6
pc. The number of compact radio sources in M82 whose origin has been determined
is now 46, of which 30 are supernova related and the remaining 16 are HII
regions. An additional 15 sources are noted, but have yet to be identified,
meaning that the total number of compact sources in M82 is at least 61. Also,
it is shown that the distribution of HII regions is correlated with the
large-scale ionised gas distribution, but is different from the distribution of
supernova remnants. In addition, the brightest HII region at (B1950) 09h 51m
42.21s +69 54' 59.2'' shows a spectral index gradient across its resolved
structure which we attribute to the source becoming optically thick towards its
centre.Comment: Accepted for publication in MNRAS. 15 pages, 9 figure
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