NAME

corrlam - apply wavelength corrections to an LETG+HRC-S event list

SYNOPSIS

corrlam [options] origfile newfile

DESCRIPTION

Provides empirically-derived corrections to photon wavelengths in level 1.5 and level 2.0 event lists to ameliorate HRC-S event position errors.

Wavelength corrections are read from an ASCII text file in a simple format - two columns containing TDETY values and their associated wavelength correction (lambda_new = lamda_orig -/+ lambda_corr for TG_M = +/- 1). New wavelengths are computed using an interpolation of these corrections from the event data TDETY values. The file is expected to be named corrlam.dat, but this can be changed with the --corrfile option.

origfile should be an L1.5 or L2 event file containing columns TDETY, TG_LAM, TG_MLAM, TG_M, TG_R and TG_D. Of these, the columns to be modified include TG_LAM, TG_MLAM and TG_R. Only events with abs(TG_M)==1 and abs(TG_D)<1.33e-2 deg are modified, all others are left unaltered. The TG_D contraint can be customized with the --maxtgd option.

OPTIONS

--help: Show help and exit.
--version: Show version and exit.
--corrfile=s: File containing wavelength corrections as a function of TDETY. The default is corrlam.dat.
--extname=s: Name of the binary table containing data to be corrected. The default name is events.
--maxtgd=f: Events whose absolute value of TG_D is greater than this are left unaltered. The default value is 1.33e-2 degrees.

HISTORY

December 17, 2004: Initial version 1.0

AUTHOR