This online applet runs barycorr
from Wright &
Eastman (2014) which calculates the barycentric velocity correction
for each UTC with a maximum error of 2.4 mm/s, compared to TEMPO2 (See
Figures 2 and 3). Mouse over the inputs for an explanation and the
required precision of inputs for desired precision of output. For 3
m/s precision, all optional fields can be ignored.
For m/s precision, one should calculate the barycentric correction
throughout the exposure and perform a flux and barycentric correction
weighted average. This error scales as the square of the exposure
time.
There is a programmatic interface to this applet. Here
is an example that recreates the values found in Table 2 (Tau Ceti
with coordinates in the Hipparcos Epoch), multiplied by c. The
optional parameters, if not specified, will default to the values
displayed here. You may also set OBSNAME to an allowed string in
observatory.pro and RAUNITS to "hours" to signify the input RA is in
hours instead of its default of degrees.
If you have made use of this calculator (or the source
code) in a scientific paper, please cite our
paper, which contains a more thorough explanation of the various
corrections involved in this calculation.