GlueX Analysis Workshop 2013

Purpose

The purpose of this tutorial/workshop session will be to give an introduction to using the Hall-D analysis tools. It is open to anyone either inside or outside the GlueX collaboration who has an interest in doing physics inside Hall-D. The tutorial will cover the basics of:

• Physics Analysis Framework
• Using Boosted Decision Trees
• Amplitude Analysis using AMPtools

The tutorial will consist of a few talks with room for questions/discussion.

Location and Time

The tutorial will take place:

DATE: July. 10-11, 2013

TIME: 9:00am to 4:30pm EDT (i.e. JLab time).

LOCATION: CEBAF Center L102 - L104

Schedule Details (Work in Progress)

Overview (Matt)

• Talk (? min): Physics Overview
  • Why amplitude analysis, underlying physics
• Talk (? min): Analysis Overview
  • Full combinatorics, kinematic fitting, some cuts in DANA and ROOT, BDT for primary signal/background separation, amplitude analysis

Monte Carlo (Matt)

• Talk (? min): Signal generation
• Talk (? min): Other standard monte carlo tools
• Exercise (? min): Generate γp→π⁺π⁺π^-n with intermediate resonances

JANA/DANA (Paul)

• Talk (30 mins): Intro to JANA/DANA (factories & plugins)
  • JANA is a framework: multithreaded, factory-based (describe concept of factories, tags (e.g. BCAL)), event-processors control the work flow
  • The primary executable (hd_root) does virtually nothing by itself, the processor in your plugin tells it what to do
  • Primary factory & plugin methods: init(), brun(), evnt(), erun(), fini()
  • Basic Analysis Classes: DKinematicData, DChargedTrackHypothesis, DChargedTrack, DNeutralShower, DMCThrown, DBeamPhoton
  • hd_dump: Prints data to screen
• Exercises (20 mins): Print basic analysis objects (DMCThrown, etc.) to screen via hd_dump and inside of plugin

ANALYSIS Library (Paul)

• Talk (25 mins): Analysis Overview
  • User specifies reaction & decay chain, library generates all particle combinations
  • Particle Combinations: Why, and why so many? (extra tracks, any PID of same q, decay products of different particles)
  • Basic example plugin: 3pi_n (go over line by line)
• Exercise (25 mins): Intro to Analysis
  • Generate 3pi_n plugin, manually histogram some quantities
• Much more to come...

Amplitude Analysis (Matt)

• Exercise (? mins): performing a single fit and analyzing projections
• Exercise (? mins): fitting the entire spectrum