Appendix C: Description of source code used for numerical simulations
Download source code
Source code consists of modules of the Cfits system. You can download the required source code with this script. Check the Cfits page for installation instructions.
C.1 Raytracing
All raytracing code is contained in the RayTrace module of Cfits.
High-resolution raytracing code is used to compute astrometric distortions due to errors in the optical surfaces and mirrors alignment.
Raytracing code is run in the ./raytrace_run directory, with results stored in the ./Raytrace directory.
Optical surface errors on M2 and M3
Files aberr2.fits and aberr3.fits.
Computing values for static astrometric distortions due to optical surface errors
- script
./runrt
in directories ./raytrace/w1, w2, w3, w4 and w5 -> w*/astrmap.txt files
- script
./combine
in ./raytrace combines the w*/astrmap.txt files -> astrmap.txt file
Computing values for astrometric distortions introduced by alignment errors
- script
./alignM2z
for distortion introduced by z motion of M2 -> ./alignM2z/astrmap.txt
- script
./alignM2z_ideal
for ideal (perfect optics) distortion introduced by z motion of M2 -> ./alignM2z_ideal/astrmap.txt
- script
./alignM3z
for distortion introduced by z motion of M3 -> ./alignM3z/astrmap.txt
- script
./alignM3z_ideal
for ideal (perfect optics) distortion introduced by z motion of M3 -> ./alignM3z_ideal/astrmap.txt
- script
./aligndetecz
for distortion introduced by z motion of detector -> ./aligndetecz/astrmap.txt
- script
./aligndetecz_ideal
for ideal (perfect optics) distortion introduced by z motion of detector -> ./aligndetecz_ideal/astrmap.txt
C.2 Data acquisition and processing
The source code used to perform the numerical simulations is written in C.
They are part of the Cfits system, so the C code calls many routines in other Cfits modules.
The raytracing code in a separate module, and is not included in the 2 files above.