NAME

SYNOPSIS

DESCRIPTION

The Suzaku task aeattcor corrects Suzaku attitude data for the effects of "thermal wobbling" caused by thermal distortions of the satellite bodies. See fhelp aeattcor for more information on that tool.

This tool (aeattcor2) further corrects the attitude data for thermal wobbling using mean event positions as a function of time.

aeattcor2 performs the following steps to produce a corrected attitude file:

1. Runs fcurve to create a time series of the mean X and Y positions of events within the input region (see regionfile parameter). The time series will have integ_time second wide bins.
2. Runs ftselect to filter out under-exposed time series bins (see minfrexp parameter).
3. Calculates the overall mean X and Y event position, optionally using sigma clipping (see clipmean, clipsigma and clipiter parameters).
4. Calculates the angular offset from the mean position as a function of time, and interpolates these differences onto the input attitude file and adjusts attitude euler angles accordingly.

NOTE: This tool does not change the input attitude, or input event files. It is left to the user to re-run the xiscoord Suzaku tool with the corrected attitude file.

CAVEATS

Only screened (clean) events should be used as input to this tool, and the region (see regionfile parameter) should be centered on a single source (preferably bright).

PARAMETERS

attitude [string]

Name of input attitude file.

outfile [string]

Name of corrected output attitude file. This can be used to correct event positions with the xiscoord Suzaku ftool.

eventfile [string]

Name of input event file to use for correction. This should be a screened XIS event file.

regionfile [string]

Name of region file to use when selecting events for mean position calculation. Any format recognized by the CFITSIO library's "regfilter" functionality can be used. The region should be centered on a reasonably bright source (does not need to be a point source).

A value of 'NONE' will cause no region filtering to be used.

(integ_time) [real]

Integration time (seconds) over which mean event positions will be calculated.

(gtifile) [string]

Name of additional GTI file to use in filtering events. Enter 'NONE' for no additional GTI filtering.

(savexycurve) [bool]

Save time-series of mean X/Y event positions, and Euler angle offsets?

(xycurve) [string]

Name of output file to contain time-series of mean X/Y event positions and Euler angle offsets.

(minfrexp) [real]

Minimum fractional exposure to include when calculating mean event positions.

(clipmean) [bool]

Calculate overall mean event positions using sigma clipping? The amount of clipping used can be controlled with the clipsigma and clipiter parameters. See fhelp ftstat for more details.

(clipsigma) [real]

Number of sigma to clip (see clipmean parameter).

(clipiter) [int]

Maximum number of clipping iterations (see clipmean parameter).

(cleanup) [bool]

Remove temporary files?

(chatter) [0,5]

Terminal chat level. 0 => no chatter; 5 => debugging

(clobber) [bool]

Overwrite existing output files?

(history) [bool]

Add history keywords?

NOTES

http://space.mit.edu/cxc/software/suzaku/aeatt.html

for information on the original tool.

LAST MODIFIED

June 2010