elcplot takes the output of lccorr as input. elcplot produces plots of the EPIC time series. These plots show both net and background light curves as well as either the Good Time Intervals (GTIs) or the background flare time series and the Fractional Exposure of each bin on a single page. Good Time Intervals are shown by a value 1.0. Bad time intervals are indicated by a 0.0. These values are shown as a histogram. If there are more than 200 GTIs, the GTIs are binned up to show a maximum of 200 intervals, for clarity. If such a binning takes place, it is indicated in the bottom right hand corner of the plot. The background flare time series is binned up in the same way as the net and background light curves. On the same plot the fractional exposure times of each bin are shown as points, plotted using a similar binning scheme to the net and background lightcurves. A portrait output is the most suitable.
The input FITS files must contain net count rates, background count rates and the associated errors, as produced by lccorr. The time series must follow a regular binning scheme (i.e. equispaced time bins) . The bin width is given by the keyword TIMEDEL. The GTI file should be that produced by tabgtigen.
Plots give count rates on the Y-axis against time on the X-axis after either TSTART (keyword in the FITS file), the default, or the user can choose to use either the start time (UTC) of the exposure (DATE-OBS keyword) by selecting tscaleoffset=0.0 or a value specified by the user in either MJD days or seconds. The user can also choose to flag the `forcestart' parameter, so that the first recorded time value of the time series is always used and the last recorded time value is the last value used. This may be useful to the user who chooses that all of his lightcurves (MOS or PN) start and finish (using evselect) at the same time for comparison, even if the DATE-OBS keyword is different for the two cameras. The time on the X-axis can also be displayed in either seconds or days as specified by the user.
elcplot allows the user to input the device type (e.g. Xwindow, Postscript, ...) for the output. The y-scale of the background counts can be forced to be the same as the source counts by setting the parameter `bkgdyscale' to `yes'. Otherwise the y-axis is scaled to the most appropriate value for the background counts.
As described in , light curves should be rebinned if necessary in order to limit the number of plotted data points to 512. If such a rebinning takes place, a warning is raised and the new bin size is indicated on the top right of the plot.