mucalc: Calculate relative proper motions of objects over multiple...

In esplint/IRACpm: Apply Distortion Correction to SPITZER IRAC Data

Description

Measures the apparent motion of stars between multiple epochs using a linear model of the motion. Optional use of the error on individual measurements normalized by the number of detections as weights.

Usage

mucalc(data, year, weight = FALSE)

Arguments

data	Array containing all coordinates organized by epoch.
year	Vector containing the time of each epoch in years.
weight	Logical: if the errors on the coordinates divided by the number of detections should be used as weights in the linear model fit. Defaults to FALSE.

Details

The structure of data should be an array with 3 dimensions. The first dimension should be the named star_id and the length of star_id (see output of read.in.data). The second dimension should be the epochs labeled ('1','2','3'...). And the final dimension labeled 'RA', 'DEC', 'e_RA', 'e_DEC', 'n_detections' (see calc.all.ch12).

This function will not work if any coordinate has no associated error.

Value

Returns matrix with columns labeled as mu.ra, mu.dec, mu.ra.sig, and mu.dec.sig, which correspond to the apparent proper motion in the RA and DEC direction, and their respective errors. Row names are the star id as indicated in the index object.

Author(s)

Taran Esplin

Examples

#This takes a while to run.
data(epochs3)
str(epochs3)
test <- mucalc(epochs3,c(0.56,5.10,9.77))
test <- test[!is.na(test[,1]),]
test[1:10,]

esplint/IRACpm documentation built on May 16, 2019, 8:52 a.m.