symmetrize

Synopsis

Adjust the tg_d values of LETG/HRC-S evt2 data to make cross-dispersion profiles more symmetric

Syntax

symmetrize infile outfile

Description

symmetrize reads in an LETG/HRC-S evt2 file (usually this will be the output of the detilt command) and adjusts the TG_D values of all events. This makes the cross-dispersion profiles more symmetric about TG_D=0 so that EEFRAC values (used in the gRMF) will be accurate even when using narrower-than-standard spectral extraction regions. See Corrections to TG_D for Wiggles, Tilt, and Asymmetry for details. Only TG_D values are affected; the output file will not exhibit any changes if displayed in sky or detector coordinates.

symmetrize is generally used in combination with the dewiggle and detilt commands--also contributed software tools--to prepare LETG/HRC-S spectra so that narrower spectral extraction regions can be used to improve the S/N of low-S/N data.

Example

symmetrize input_evt2.fits output_evt2.fits clobber+

Run the program with the clobber parameter enabled.

Parameters

name	type	ftype	def	min	max	reqd	stacks
infile	file					yes	no
outfile	file	output				yes	no
sfile	file		${ASCDS_CONTRIB}/data/eefracIDEAL09.symm78corr				no
verbose	integer		0	0	5
clobber	boolean		no

Detailed Parameter Descriptions

Parameter=infile (file required stacks=no)

Input FITS file event list with columns TG_D and TG_MLAM.

Parameter=outfile (file required filetype=output default= stacks=no)

Output FITS file event list with modified TG_D column.

Parameter=sfile (file default=${ASCDS_CONTRIB}/data/eefracIDEAL09.symm78corr stacks=no)

File containing the TG_D correction as a function of wavelength.

Parameter=verbose (integer default=0 min=0 max=5)

Tool chatter level

Controls the amount of information tool prints to the screen.

Parameter=clobber (boolean default=no)

Remove outfile if it already exists?

About Contributed Software

This tool is not an official part of the CIAO release but is made available as "contributed" software via the CIAO scripts page. Please see this page for installation instructions.

Bugs

See the bugs page on the CIAO website for an up-to-date listing of known bugs.

Refer to the CIAO bug pages for an up-to-date listing of known issues.