grisudet cherenkov utilities
A program for the analysis of simulation data
Full Documentation coming soon.
In ./Analysis, if you type make veritas, it will compile analysis.cpp, linking to the vbf (VERITAS binary data format library) and mysql as well as including veritas.h which contains veritas specific procedure to deal with the tracking information and reading of VERITAS data. In the present version, reconstruction methods might not all properly take into account the VERITAS tracking information.
THREE RECONSTRUCTION METHODS IMPLEMENTED AND TESTED
With this version, you may use the analysis code to generate Hillas parameters from a single ACT telescope or an array of telescopes. The code accepts simulation files from grisudet.c or real data files from the VERITAS prototype telescope passed through the raw2grisu code. The analysis code accepts either QADC input files or FADC input files.
The code calculates the pedvars, does pedestal
subtraction, and pixel cleaning. The file, analysis.pilot, manages the
operation of analysis. Should you wish to use a pilot file with a
different name, just place the new filename on the analysis command
line. The default for no command-line filename is analysis.pilot.
Compiling with the option ("make stereo")
includes the reconst_shower.h file thus enabling the reconstruction
methods for array simulations. This option requires the use of the gsl
(gnu scientific library) minimizer functions. The resulting .rsl
file contains the reconstruction details as well as the global image
width (in degrees on the camera) and the global shower width (in meters
parallel to the telescope plane). The analysis.pilot file
contained in this package and given below presents substantial
documentation on the use of the reconstruction methods.
FADC Sums: There are two summing operations.
The analysis.pilot file specifies a sample number where summing begins and two sample numbers where summing stops. The code can produce two FADC sums, each beginninig at the start_sum channel and ending respectively at each stop_sum channel. The output file contains two sets of Hillas parameters, one for each sum region.
The output file will contain Hillas parameters for all options set for grisudet output files. That is, it may contain Hillas parameters for QADC or FADC or N-type grisudet output (or any combination of these three types of output).
Cleaning Operations: There are now two options for image cleaning
Image cleaning is in units of either pedestal widths (as is customary) or in units of digital counts. The analysis.pilot file specifies the cleaning mode and the cleaning parameters. It specifies two sets of cleaning parameters, one for each of the two FADC sums.
Pedestal Options: The analysis.pilot file specifies one of four pedestal options:
Pedestals and pedestal widths may be determined from specific pedestal records in the input data stream or read from a separate pedestal/pedestal width file.
Pedestals and pedestal widths determined from input records may be written to a pedestal/pedestal width file.
Pedestals and pedestal widths may be determined for each input record using initial FADC samples with ranges specified in the analysis.pilot file.
Gain and Timing Operations: These options accomodate specific time delays in each channel and non-uniform gains, both determined by laser runs, either in the real data or in simulated data.
Use gain factors and time delays given for each pixel in the telescope configuration file
Read the gain factors and time delays in a gain_time file.
Write a gain_time file where the input stream contains laser or nitrogen flasher data (either real data or simulated data)
Analysis requires these files:
GrISU/Analysis/reconstruct_shower.h ("stereo" only)
Analysis Input Parameters and Input Files
Analysis Log File
Analysis Code Description
Verification and Testing