Testbeam Reconstruction Details

Installation: http://eutelescope.web.cern.ch/content/installation

After installing and sourcing environment (build_env.sh) the main directory is $EUTELESCOPE

Useful directories

src (include): contains processor source code (headers)
build: recompilation after code changes
- > cmake ..
- > make install
jobsub: includes examples folder with template reconstructions
pixgeo: where geometry files for sensor libraries are stored
external: includes eudaq code

Working Folder

In working folder: $EUTELESCOPE/jobsub/examples/SOME_EXAMPLE

Steering folder: Steering files for each reconstruction step. Each file contains list of Processors executed in the step
Configuration file: Specifies user directories: data directory, output directories
- general parameters: number of events, output frequency
- steering parameters: specific to each reconstruction step
Gear file: Specifies devices and physical positions/orientations of set-up
Runlist file: Parameters specific to particular runs
Output directories: Store histograms and hit sets form each reconstruction step

OUTPUT DIRECTORIES

These are specified in the config file.

In working folder: $EUTELESCOPE/jobsub/examples/SOME_EXAMPLE/output

histograms: Root files with distribution plots produced in reconstruction step
lcio: Input/output collections used by EUTelescope and passed between steps
database: Parameters used by the reconstruction
logs: Log files for each jobsub execution

Each file has standard prefix (set in config): runXXXXXX

XXXXXX is run number specified on execution -always six digits

RECONSTRUCTION STEPS:

There are five basic steps to run the reconstruction chain (i.e. to transform raw data into analysis ready data):

converter: Read in telescope and DUT hit information, from native DAQ to LCIO format
clustering: Combine individual hits on each plane to hit clusters on each plane
hitmaker: Globally orient planes
align: Global alignment of planes: based on pattern recognition & track fitting
fitter: Generate tracks --> device resolution

Parameters used in each reconstruction step are defined between config, runlist and steering files: config includes global parameters; runlist includes run specific parameters; and, gear file has the sensor specification. Other values can be found in the individual steering files, though any non-global values can be defined elsewhere. Parameters are refered to across files using @NAME@ syntax.

Other steps are definable in the steering directory. All follow the form of a recipe of processors (in execution order) with processor definitions below (no order required). The source coude for each processor can be found in $EUTELESCOPE/src (include) by identifying the processor "type" specified at the top of each processor definition in the steering file.

The basic steps are expanded on below.

Converter

Two functions

Decode raw files: telescope plane and DUT hit information
- Translated into LCIO hits (format of EUTELESCOPE), Uses eudaq to convert from native format.
- Converter file found in: $EUTELESCOPE/external/eudaq/<version>/main/lib/src
check for hot pixels -> create list for masking later

REQUIRES:

Specification of planes: gear file & steering file
- Plane names (i.e. numbers) to expect
- Correct specification of devices (# detector elements) in gear file
Library of detector geometry required

SET: