org.lcsim ILC Reconstruction and Analysis

Tony Johnson

SLAC

March 2005

org.lcsim ILC Reconstruction and Analysis Earlier Packages

hep.lcd Reconstruction and Analysis LCIOPlugin

Goals of org.lcsim Components

Conditions Handling Geometry Access Event Access Reconstruction Analysis Tools JAS Plugin

Accessing Code Status and Plans

hep.lcd Overview

Java based analysis reconstruction and analysis package In use for 5+ years Runs standalone or inside JAS Full Reconstruction (tracking+calorimetry) Analysis Tools (including WIRED event display) Fast MC

Smeared tracks and calorimetry clusters Physics Tools (Vertex Finding, Jet Finding) Beam Background Overlays Contributed Area

Analysis Utilities and sample analyses provided by users

hep.lcd Physics Utilities Physics Utilities

4-vector, 3-vector classes Event shape/Thrust finder Jet Finders

Many kT algorithms implemented (e.g. Jade and Durham ) Extensible to allow implementation of other algorithms

Topological Vertexing Implementation of SLD’s ZVTOP

Event Generators Framework Diagnostic Generator

User-defined particle mix, momenta and vertices. Framework for reading stdhep files Generator interface for direct connection to (fortran) event

generators PYTHIA, HERWIG, ISAJET, …

Beam background overlay

Full Reconstruction Tracking

Hit Smearing/Efficiency (detector simulation puts out “perfect” hits) Random Background overlay Track Finding:

Full pattern recognition in the Central Barrel region Tuned for Large and Silicon Detectors

Track Fitters: SLD Weight Matrix Fitter Can do Single Detector or Combined fit (e.g. VTX+TPC)

Calorimetry Cluster Finding

Several Clustering Algorithms Currently Implemented Cluster QA package developed

Cluster Refinements Combine HAD + EM clusters Endcap + Barrel overlap region Identify cluster as originating from charged/neutral hadron, EM

Recent improvements to hep.lcd Ported to work with JAS3 (T. Johnson) New digitization routines being added (N.Sinev) Cluster identification code (G. Bower) Cluster diagnostic package (R. Cassell) Improved Stepper (C. Milstene) Forward Tracking (N. Graf) Flavour Tagging (D. Jackson) Particle ID (B. Wilson, S. Rolnick) Support for Non-Projective geometries (G. Lima) “Garfield” track-finder (E. von Toerne et al)

hep.lcd analysis tools

Tutorial: http://jas.freehep.org/jas3/Tutorial/index.html

hep.lcd package pros-and-cons Features:

Can run standalone or inside JAS Runs on almost any platform No dependencies on pre-installed software or network

connections. Can install and run in <15 minutes from Snowmass 2001 CD

Problems: IO based on old LCD SIO format No way to write output from reconstruction Dependent on old geometry description (detector.ini)

limited to cylindrical dectectors

LCIO plugin for JAS3 Works with any LCIO file Diagnostic tools allow to step through and view events

LCIO plugin for JAS3 Event Analysis

Wizard will create outline of analysis, and

can include sample analysis code. Main

routine allows running outside of JAS

Using WIRED with LCIOPlugin LCIO files can (but don’t necessarily) contain positions

of all hits, but no detector geometry info except “detector name”

LCIOPlugin+WIRED can view hits for any file, but these are hard to visualize without detector LCIOPlugin can read external

HepRep2 file describing detector geometry Location currently needs to be specified HepRep file (xml) can be generated:

by hand (quite easy for simple geometry) by Geant4 using HepRep2 writer (perhaps

with some filtering to remove excess details)

By program using Java or C++ HepRep API

LCIOPlugin with WIRED4

LCIOPlugin with WIRED4

LCIO Plugins pros-and-cons

Features: Not dependent on any detector specific assumptions Simple environment for debugging problems with LCIO and

writing simple analysis routines Detector independent event display

Problems: No connection to reconstruction or analysis tools Detector geometry must be specified by hand Existing LCIO API does not emphasize user-friendliness

org.lcsim Reconstruction and Analysis package

org.lcsim Goals Retain core functionality from hep.lcd package

Full suite of reconstruction and analysis tools available to all LCIO users

Update to use LCIO for IO and as basis for simulation, raw data and reconstruction event formats Isolate users from raw LCIO structures

Update/simplify framework using experience from hep.lcd Provide good tutorial documentation

Internationalization Try to make package independent of detector, geometry

assumptions so can work with any detector Read properties of detectors at runtime

Update to Java 1.5 Many improvements since hep.lcd framework was created.

Ability to run standalone or in JAS3

org.lcsim Conditions Database Goal: Using “detector name” in LCIO file

Provide access to a extensible set of conditions including: Detector Geometry Algorithm Specific Constants

E.g. FastMC smearing parameters

Don’t make assumptions about format of data Don’t rely on internet access, or local database

installation Make it easy for users to define new detectors

org.lcsim Conditions Database:Implementation Detector Constants stored in .zip file

Typically contains: Compact geometry file Set of (ascii) constants for standard algorithms

Could additionally contain: Arbitrary files (xml, ascii, binary) needed by other algorithms Other geometry formats (HepRep, LCDD) Links to database (e.g. for access to LCCD).

To define a new detector just create a new .zip file.

org.lcsim Conditions Database:Implementation org.lcsim locates file based on detector name by:

Looking in alias.properties file in User’s home directory Built-in to org.lcsim software On www.lcsim.org website*

If translated name is a URL (file:, ftp:, http) Read .zip file at specified location

Search for .zip file in ~/.lcsim/detectors Built-in to org.lcsim software In http://www.lcsim.org/detectors*

*Downloaded files are cached locally for future use

org.lcsim Conditions Database:Accessing constants

Later on if constants change, listener will be called

Constants are accessed by name (actually path in zip file)

Geometry Access

Geometry Access is build on top of conditions database Framework reads and decodes compact geometry

description. User can iterate over detectors or access detector by name or id

Provides access to detector properties (# layers etc). “Shape” of detector

Framework builds “IDDecoder” objects for each hit collection. ID decoder unpacks ID’s in LCIO files

Provides access hit position, detector layer etc. Can provide additional utilities, for instance list of neighboring cells

in calorimeter

org.lcsim Drivers, Event Access Reconstruction and Analysis Code is written by extending Driver

class. Most code extends only a single method

process(EventHeader event) which passes in EventHeader through which all event data,

conditions, and geometry is accessed. EventHeader maintains features which users liked from old

hep.lcd framework, but adds compatibility with LCIO events All LCIO data is accessible. Arbitrary user data, either collections or single objects can be

added to event. Event can be written out

Currently only objects understood by LCIO are written out MCParticles, Hits, Clusters, Tracks, Reconstructed Particles (can include

Jets, Vertices) Maybe be able to use LCIO “GenericObjects” to write out more in future.

Reconstruction: Clustering

Several Clustering Algorithms now included Cluster Cheater

uses MC information Nearest Neighbor

Clusterer Cone Clusterer

Algorithms can be run in parallel for comparison

org.lcsim: IO Can read LCIO files, stdhep files (for FastMC) Can write LCIO files

org.lcsim: JAS Plugin

The org.lcsim can be used standalone, or inside JAS3. Same code can be used in both places, so easy to move back and forth E.g. develop in IDE and run in JAS3 E.g. develop in JAS3 and run in batch

JAS3 plugin adds: Example Analysis Code Event browser (similar to LCIOPlugin) Easy viewing of AIDA plots WIRED event display integration

org.lcsim: Examples

org.lcsim: Examples

org.lcsim: Plot Viewing

Org.lcsim: WIRED event display

org.lcsim Status Physics Utilities - done

stdhep reader 3, 4-vector utilities diagnostic generator Jet finder, event shape utilities

Conditions framework – done Ability to read detector constants from “zip” file To define new detector just create new zip file and place on web

File is read and cached locally Ability to read compact geometry file

Driver framework – done Fast MC – done IO Framework – done Event Access – working, still being improved Event Display interface – mostly done Reconstruction

Clustering – done Tracking – TRF - in progress, very nearly done Vertex finding – needs port from hep.lcd Hit digitization – needs port from hep.lcd Swimmer, cluster analysis tools, pfa, etc. – needs port from hep.lcd

Accessing Code

To use you can just download JAS3, and then use the JAS3 Plugin Manager to install the org.lcsim Plugin http://confluence.slac.stanford.edu/display/ilc/

Installing+JAS3 To add new software to the framework check

out the software from CVS and build using “maven” http://confluence.slac.stanford.edu/display/ilc/Buil

ding+org.lcsim+software

org.lcsim: To Do List Improve Documentation/Tutorials Continue to (work with others to) migrate reconstruction algorithms

from hep.lcd Strongly encourage people to work in CVS:

If we make changes to event access etc. we can update all code in CVS using refactoring tools

Remove divergences from LCIO standard 100% compatible with LCIO file format, philosophy Attempts to make event access easier should be merged back into

LCIO standard interfaces? LCIOPlugin and org.lcsim plugin should be merged

Test ability to interoperate with other software, e.g. slic, marlin, mokka, jupiter, brahms, lelaps, etc.

Produce new CD, hopefully well before Snowmass meeting. Online weekly clinic using VRVS/ES net?