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Old March 1st 07, 06:47 PM posted to sci.astro.research
Oh No
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Posts: 433
Default Doppler Tests on Local Stars

Thus spake Stupendous_Man
... I have for some while been looking for a way
to test this, and finally came up with a simple statistical test on
local stars. For stars in perfect circular orbits, Doppler shifts,
together with the teleconnection correction, would cancel, but real
measured velocities show a wide random scatter. We can't measure the
true motion of any individual star without using Doppler, but if the
teleconnection is right then the radial component of velocity will be
overstated. I have been looking for a way to show that quoted radial
motions are systematically large compared to transverse ones. I


Have you included the systematic deviations from random
velocities due to the differential rotation of stars in the disk
and their actual, non-circular motions?

Suppose stellar orbits are elliptical, not circular.


Indeed, they are. More so than I had naively imagined.

Then stars
in our local neighborhood will be a mixture of populations,
which we can describe as a) stars with semi-major axes
smaller than the Sun's, which are currently at the apoapsis
of their orbits, b) stars with semi-major axes about the same
as the Sun's and c) stars with semi-major axes larger
than the Sun's, which are currently at the periapsis
of their orbits. The orbital velocities of these populations
will be different in systematic ways. The number of stars
from each population which we measure locally depends
on the overall radial gradient of stellar density in the
Milky Way, and on some geometry.


It is extremely complicated. Its not actually possible to divide the
whole into discrete populations like this. Moreover not all stars have
the same eccentricity. Although older stars give a fairly random, and
not exactly ellipsoidal mix (nearer three quadrants in the U-V plane,
though more even in the U-W and V-W planes), young ones do not and
contribute bulk motions.

It is possible that the effect of these different
populations could mimic the effect you see.


Certainly not all the effects. Even if some of the effects could be
mimicked in the manner you suggest (and I don't think they can) your
argument does not apply to halo stars, which gave the strongest
correlation of any population, rejecting the standard prediction with
99.999% confidence. Nor does it apply to correlations on the W axis,
which gave the highest correlation of any axis, rejecting the standard
prediction with 99.999999% confidence.

The fact that these two tests gave such strong results is entirely in
accordance with the teleconnection prediction. It is expected that the
Doppler error is largest for faster moving stars, and it is expected
that the correlations should show up best when the distribution is more
uniform.


Regards

--
Charles Francis
moderator sci.physics.foundations.
substitute charles for NotI to email