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./toolbox
chdoppler.pro

Last modification date:
Sun Jul 27 03:20:02 2014

chdoppler

function chdoppler(ra, dec, julday, [obspos=double [2]], [/light])

computes the projected velocity of the telescope wrt six coordinate systems: geo, helio, bary, lsrk, lsrd, gal negative velocities mean approach The standard LSR is defined as follows: the sun moves at 20.0 km/s toward ra=18.0h, dec=30.0 deg in 1900 epoch coords Fully vectorized. All three arguments must have the same dimensions.

This code came via e-mail from Carl Heiles via Tom Bania on 11/04/2004. Updated using code found via google from same source on 11/30/2009. Local changes:

Previous revision history: carlh 29oct04

Returns
The velocity in km/s, or as a faction of c if the keyword /light is specified. the result is a 6-element vector whose elements are [geo, helio, bary, lsrk, lsrd, gal].
Uses
baryvel precess juldaytolmst
Version
$Id$

Parameters
ra
in, required
The source ra in decimal hours, equinox 2000
dec
in, required
The source dec in decimal hours, equinox 2000
julday
in, required
The julian day

Keywords
obspos
in, optional
double [2]
observatory position [East longitude, latitude] in degrees. Uses the GBT position if not specified.
light
in, optional
boolean
When set, returns the velocity as a fraction of c


Produced by IDLdoc 1.6 on Sun Jul 27 03:20:14 2014