414 research outputs found
Mexico\u27s New Foreign Investment Regulations: A Legal Analysis
new Regulations seem to open Mexico up for foreign investment, they cause potential legal problems of which an investor must be aware. The Regulations are vague and confusing in many areas, and the Mexican government exercises great discretion in interpreting many of its provisions. Moreover, the Regulations, as they are written, appear to violate certain provisions of Mexico\u27s Constitution. 7 If so, a potential investor may one day find, that though he followed the Regulations to the letter, he nonetheless violated Mexican law. This could have serious ramifications for both himself and his investment
Hubble Space Telescope Images of the Subarcsecond Jet in DG Tau
We have applied a new restoration technique to archival [O~I], H, and
continuum HST images of DG~Tau. The restored [O~I] and H images show
that DG~Tau has a jet with a projected length of 25~AU and width 10~AU,
and is already collimated at a projected distance of ~40~AU (0\farcs25)
from the star. Such a narrow width and short collimation distance for a stellar
jet places important constraints on theoretical models of jet formation.Comment: 6 pages, 3 figures included. All in postscript, please read
instructions at the beginning of the file. Accepted by the Ap.J. Letter
Model for Gravitational Interaction between Dark Matter and Baryons
We propose a phenomenological model where the gravitational interaction
between dark matter and baryons is suppressed on small, subgalactic scales. We
describe the gravitational force by adding a Yukawa contribution to the
standard Newtonian potential and show that this interaction scheme is
effectively suggested by the available observations of the inner rotation
curves of small mass galaxies. Besides helping in interpreting the cuspy
profile of dark matter halos observed in N-body simulations, this potential
regulates the quantity of baryons within halos of different masses.Comment: 4 pages, 2 figures, final versio
A Catalogue of Field Horizontal Branch Stars Aligned with High Velocity Clouds
We present a catalogue of 430 Field Horizontal Branch (FHB) stars, selected
from the Hamburg/ESO Survey (HES), which fortuitously align with high column
density neutral hydrogen (HI) High-Velocity Cloud (HVC) gas. These stars are
ideal candidates for absorption-line studies of HVCs, attempts at which have
been made for almost 40 years with little success. A parent sample of 8321 HES
FHB stars was used to extract HI spectra along each line-of-sight, using the HI
Parkes All-Sky Survey. All lines-of-sight aligned with high velocity HI
emission with peak brightness temperatures greater than 120mK were examined.
The HI spectra of these 430 probes were visually screened and cross-referenced
with several HVC catalogues. In a forthcoming paper, we report on the results
of high-resolution spectroscopic observations of a sample of stars drawn from
this catalogue.Comment: 7 pages, 4 figures. ApJS accepted. Full catalogue and all online-only
images available at
http://astronomy.swin.edu.au/staff/cthom/catalogue/index.htm
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