FlexIRF, developed as a test bench for the future Cherenkov Telescope Array Data Models, is a tool to read/write an Instrument Response Function into a single FITS file. Due to the large number of external parameters affecting Imaging Atmospheric Cherenkov Telescopes performance, the IRF is required to be defined in a wide phase space to reduce systematic uncertaintie. This code attemps to provide more flexibility to current IRF generators.
The code is written in C++, making use of the CFITSIO library. Few dependencies, to be removed in the future, make use of ROOT libraries (current standard in gamma-ray astronomy).
License: Apache v2
Currently, the software uses the following dependencies:
git dpkg-dev make g++ gcc binutils libx11-dev libxpm-dev libxft-dev libxext-dev cmake autoconf
It also uses CFITSIO library ("libcfitsio3" "libcfitsio3-dev" packages on ubuntu machines) and swig, although with no python working wrapper yet.
ROOT is currently an optional library used by some executables, but will be removed in the future.
Build git version using:
./setup.sh
cd build && make all && cd ..Although this project still lacks proper documentation, several very simple macros were created to show the typical use cases of the different classes:
IRFsimpleWriteIrf.cc:
This simple macro generates a fits file "examples/testEffArea.fits" containing a mock effective area into a FITS file. To run it, simply execute:
bin/IRFsimpleWriteIrfIt shows how "AxisType", "VarType" and other variables are used in the definition of a "GIRFAxis" object, and then how the IRF element is created using a "GIRFPdf" and introduced into the generic "GIRF".
IRFsimpleWriteParamIrf.cc:
Similarly as "IRFsimpleWriteIrf", this script writes a parameterized effective area (1D gaussian) into a FITS file, stored in "examples/testParamEffArea.fits":
bin/IRFsimpleWriteParamIrfIRFsimpleWriteIrfSerialization.cc:
Again an example macro nearly idenatical to "IRFsimpleWriteIrf". In this case, 2 different serializations are used to write the same IRF into two different FITS files: "examples/testEffAreaIMAGE.fits" and "examples/testEffAreaBINTABLE.fits". To run this script execute:
bin/IRFsimpleWriteIrfSerializationIRFsimpleReadIrf.cc:
This script reads a previously generated GIRF FITS file (such as "examples/testEffArea.fits" or "examples/testParamEffArea.fits"), loading it into a GIRF object, extracting an effective area as a "GIRFPdf" and printing it (& drawing it, if you have ROOT properly installed, generating the "plot.png" file). To run it, execute:
bin/IRFsimpleReadIrf examples/testEffArea.fitsor
bin/IRFsimpleReadIrf examples/testParamEffArea.fitsNote the use of the "GIRFConfig" class, used to extract the IRF with a specific configuration and valid range. Also note the process to read an IRF element is identical in the case of a binned or parameterized axis.
The following are older and more complicated (working, but nearly deprecated) examples.
IRFconverter_root2FITS:
This tool takes a dummy configuration file and (for now), the performance file "Performance_2Q_Aar_50h_20150217.root". Run the following command from the build directory to convert the root histograms in the performance file into the fits format being developed at IFAE.
Example -
bin/IRFconverter_root2FITS dummy/dummyconfig.txt prodfiles/Performance_2Q_Aar_50h_20150505.rootOutput will be
testRoot2FITS_converter.fits
IRFgenerator_rootio:
For the moment, this program reads in a dummy configuration file (located in dummy/dummyconfig.txt) and a CTA MC analysis file (located in prodfiles/DESY.d20140105.Erec1.V3.ID0NIM2.prod2-Tenerife-NS.N.2NN-MST.180000s.root) and generates three fits files ( Ebias_offaxis.fits (2D), ERes_offaxis.fits (2D) and AngRes_offaxis.fits (3D) ) in the build directory
Example -
In the parent directory run
./bin/IRFgenerator_rootio dummy/dummyconfig.txt prodfiles/DESY.d20140105.Erec1.V3.ID0NIM2.prod2-Tenerife-NS.N.2NN-MST.180000s.rootOutput will be
ERes_offaxis.fits, Ebias_offaxis.fits and AngRes_offaxis.fits