9 Time Series Data

9.1 Input of Data

Time series data handled by TSP can come from a variety of sources, and can range from simple single channel photometry, to multichannel polarimetric data. There are a number of routines which allow time series data to be read into the system:

RHATHSP

— Reads high speed photometry data taken with the Hatfield polarimeter, working in its 5 channel photometer mode.

RHATPOL

— Reads 6 channel polarimetry data taken with the Hatfield polarimeter.

RHSP3

— Reads tapes created with the HSP3 high speed photometry system at the AAT.

RIRPS

— Reads time series infrared photometry obtained with the AAO Infrared Photometer Spectrometer (IRPS).

RTURKU

— Reads files containing data from the University of TURKU UBVRI polarimeter. These data sets have 5 channels and can include either linear or linear plus circular polarization.

Time series photometry and polarimetry can also be extracted from time series imaging data as described later.

9.2 Processing Data

Processing of time series data includes the following options.

LTCORR

— This corrects a time series dataset for light travel time, yielding a heliocentric or barycentric time axis.

TEXTIN

— This corrects a time series dataset for atmospheric extinction.

TMERGE

— This merges two time series datasets. The two datasets must have the same number of channels. Because TSP does not require the time axis of datasets to be evenly spaced it is possible to combine observations taken even years apart into a single file.

TBIN

— Bin a time series into time bins of a specified size.

TDERIV

— Calculate a new time series which is the time derivative of the intensity data in a time series.

9.3 Plotting Time Series Data

The following commands are available for plotting time series data:

TSPLOT

— Plots time series data against time. There are lots of options to plot up to six items which can be different channels, polarization components etc. The plotted data can be binned if necessary.

PHASEPLOT

— Plots time series data against phase on some period. There are similar options to those in TSPLOT.

QPLOT

— A ‘quick’ version of TSPLOT with less options.