STARPROC

Name

starproc

Purpose

Collect and process final (standard) star photometry

Description

This program processes the accumulated stellar photometry into final
averages. The data are generated by REDUCTOR and have been saved
to the final output directory (set via PATH keyword).
This program can reduce all stars in this directory or just one star.
On starting the program, the contents of the photometry directory are
scanned and a selection widget is presented. You can either choose
a single object by its name or choose the item "ALL". If you do one
object, it will be analyzed and plots of the data are provided. If
you choose ALL, each star in turn is analyzed but no plots are generated.
The photometry for each star is examined and a mean for each color is
found. The mean comes from weighted average of all points. After the
mean is determined, the photometry is examined against the mean. Any
point found to be greater than 5 sigma from the mean is discarded and
the mean is recalculated. If plotted, these removed points will plot
with a different symbol (filled circle with overlayed asterisk). This
point removal continues until no points are removed or 10 passes are
made.
The final uncertainty for the combined photometry is comes from taking the
standard deviation of the data and dividing by the sqrt of the number
of nights of data (NOT the number of points). My assumption is that
the errors tend to be systematic within a night but random from night
to night. Obviously, the photometry will not be particularly trustworthy
until there are quite a few nights in the average.
The final output file is a listing, one line per star, of the final averaged
values. Left to right, the values are:
Name, B (mag, err, npoints, nights, chisq),
V (mag, err, npoints, nights, chisq),
R (mag, err, npoints, nights, chisq),
B-V (color, err)
V-R (color, err)

Calling Sequence

starproc[,PATH=path]

Inputs

This is an interactive program, there are no explicit inputs.

Optional Input Parameters

Keyword Input Parameters

PATH - Directory where the star data is located. Default is
/net/frakir/raid/buie/photometry/stars

Outputs

output is written to a file ALL.DAT in the stars directory.

Keyword Output Parameters

Common Blocks

Side Effects

Restrictions

Procedure

Modification History

97/02/27, Written by Marc W. Buie, Lowell Observatory
2004/02/09, MWB, changed default for PATH