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Synopsis

lardon [options]
At minimum you must provide -det, -run, -sub, and at least one reconstruction mode flag (-trk and/or -pds).

Detector and run flags

These flags identify the data to process. -det and -run are always required. -sub is required unless you supply -file.
-det
string
required
Which detector to process. Must be one of: cb1top, cb1bot, dp, cbtop, cbbot, 50l, pdhd, pdvd.See Supported Detectors for descriptions of each option.
-run
string
default:"-1"
required
Run number to process (e.g. 39229). Must be provided explicitly; the default of -1 causes LARDON to exit with a usage message.
-sub
string
required
Subfile name to read (e.g. 24, 1_a, 0). Required unless using -file.

Reconstruction mode flags

At least one of these flags must be set, or LARDON will exit with a usage message.
-trk
boolean
Enable TPC/charge reconstruction. Processes wire signals, finds hits, builds 2D and 3D tracks.
-pds
boolean
Enable PDS/light reconstruction. Processes photon detector signals.
PDS reconstruction is only configured for pdvd and cbbot. Other detectors (pdhd, cbtop, cb1top, cb1bot, dp, 50l) do not have PDS geometry configured. The README notes PDS does not work for pdhd.

File location flags

LARDON searches for raw files using the paths defined in each detector’s path.json. The flags below help it locate the right file when data is stored in non-default locations or named with additional components.
-flow
string
default:"-1"
Dataflow number (e.g. 4). Used when the raw file was written by multiple dataflow/datawriter applications (high trigger rate, long readout windows).When both -flow and -writer are left at their defaults (-1), LARDON treats them both as 0 and omits the flow/writer suffix from the output filename. When either is set to a non-default value, the suffix _{flow}{writer} (and optionally _s{server}) is appended to the output filename.
-writer
string
default:"-1"
Datawriter number (e.g. 0). Used together with -flow to identify files written by specific writer processes. See -flow for suffix behaviour.
-serv
string
default:"-1"
DAQ server number (e.g. 5). May be needed for some PDVD runs. You can find it in the raw filename under the -s0x- component (e.g. -s05--serv 5).
-hash
string
default:"xx/xx"
Hashed subdirectory where the data file lives (e.g. 86/ad). LARDON searches both the top-level data directory and several hashed subdirectory patterns. Use rucio to look up the correct hash for a given file.
-file
string
Full path to the raw file. Supports local paths and XRootD URLs (e.g. root://eosserver.cern.ch//eos/.../file.hdf5).When -file is given, LARDON extracts the run number, subfile, dataflow, datawriter, DAQ server, and detector directly from the filename. You do not need to pass -run, -sub, -det, etc. separately.Use this option for files outside of CERN/Fermilab or copied to a non-standard location. Ensure your XRootD authentication (justin / rucio) is configured before use.

Event selection

-n
number
default:"-1"
Number of events to process. -1 (or omitting the flag) processes the entire file.
-skip
number
default:"0"
Number of events to skip at the start of the file before processing begins.
-event
number
default:"-1"
Analyse only a single specific event. Setting -event 11 is equivalent to setting -n 12 -skip 11. Takes precedence over -n and -skip when provided.

Output control

-out
string
default:""
Extra suffix appended to the output HDF5 filename (e.g. one_event). A leading underscore is added automatically. If omitted, no suffix is added.Output filenames follow the pattern:
{detector}_{run}_{sub}[_{flow}{writer}[_s{server}]][_{outname}].h5
Without -job, the file is written to $LARDON_RECO/. With -job, it is written to the current working directory.

Special modes

-pulse
boolean
Charge pulsing/calibration data mode. LARDON finds and fits pulses in the waveforms instead of running the standard track reconstruction.
Pulsing reconstruction is significantly slower than standard reconstruction. Expect substantially longer run times.
-online
boolean
Online monitoring mode (LARDONline). Produces an event display and control plots live during processing. Intended for use at the detector site during data-taking.
-job
boolean
Flag that LARDON is running as a batch job. Changes output path behaviour: the output HDF5 file is written to the current working directory instead of $LARDON_RECO.
Gallery visualisation mode. Displays data using an effective channel mapping so that tracks appear continuous rather than broken across readout boundaries.Accepted values: beam, top, bottom, both.
  • beam — shows only channels relevant to the beam track, zoomed around the expected beam time.
  • top / bottom — shows the top or bottom drift volume.
  • both — produces two separate images for the top and bottom volumes.
Gallery mode is only supported for pdvd data. Running with any other detector will cause LARDON to exit.

Required flag combinations

GoalMinimum flags required
TPC reconstruction-det -run -sub -trk
PDS reconstruction-det -run -sub -pds
TPC + PDS-det -run -sub -trk -pds
Single eventadd -event <n>
Non-default file locationadd -flow -writer and/or -hash -serv
File from XRootD path-file <path> -trk and/or -pds
Pulsing calibration-det -run -sub -pulse
Gallery visualisation-det pdvd -run -sub -gallery <mode>

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