Dalitz Analysis Fitting Tools Survey

HOT item

What this survey is?

Dalitz fitting tools "checklist"

• Software basis (Fortran, ROOT, RooFit, EvtGenBase, etc.)
• B and/or D decays
• Fit techniques: unbinned/binned maximum likelihood (UML/BML), chi2
• Goodness-of-fit (GOF): likelihood, chi2, adaptative binning
• Dalitz model(s):
• Dynamics: isobar (Breit-Wigner), K-matrix/P-vector, partial waves (PWA)
  
• Spin formalism: Helicity  (ps), Zemach Tensors (pdf) (covariant and non-covariant), partial waves
  
• Normalization of amplitudes: toy MC, numerical, analytical
  
• Efficiency and mass resolution (for narrow resonances) treatment
• Background Dalitz shapes and characterization (mES, DeltaE, Fisher, mD, tag info)
• Fit support for masses and widths
• How are the fit fractions calculated?
• Visualization of results (ALL)
• Input: flat and/or ROOT file (ALL)
• Any other specific feature (CVS availability, documentation,...)?
  

Tools and filled checklist

• Charm AWG
• Bari (A. Palano)
• Cincinnati (B. Meadows)
• Checklist:
• Custom, Fortran based
• D decays
• UML
• Likelihood, chi2 and adaptative binning GOF
• Isobar model (BWs, Flatte, LASS), PWA
• Helicity and Zemach tensors (no covariant)
• Normalization: phase space MC weifghted by the polynomial efficiency
• Efficiency correction: fitted 3rd order polynomial. No mass resolution
• Background: Gaussian to describe D
• Fractions computed as:

• Breco AWG
• D0(Dalitz)K-
• RooDKDalitz
• General framework, RooFit and EvtGenBase based
• D decays, can easily be adapted for B decays
  
• RooBenDalitz
• Custom, RooFit based
• Essentially, a custom version of RooDKDalitz optimized for D0->Kspi+pi- (3-body) studies and tunning
• Simple
• Fast
• Addition of channels requires hard coding
• Complementary to RooDKDalitz
• Available in BaBar CVS repository: cvs co RooBenDalitz
  
• D*-a1+
• DOOM (Dalitz Object Oriented Modeling)
  
• General framework, ROOT and StatTools based
• Potentially for B and D decays
• Now applied to study of 3 pion system in the B->D*3pi decay
• UML
• Isobar model with covariant Zemach tensors
• Likelihood GOF
• Normalization: phase space MC
• Efficiency correction: not yet available
• Background: SB mES
• Mass and width fitting: could be implemented if required
• Fit fractions: account for interference
• Visualization based on toy MC random extraction
• Available in BaBar CVS repository: cvs co BToDstar3pi
• Optimized for batch running rather than interactive analysis
  
• D(*)pi-pi- (DJ states)
• BToDjFittingTools
• General framework, RooFit and EvtGenBase based
• EvtGenBase classes for amplitude calculation (Pto3P classes)
• Potentially for B and D decays (P->PPP and P->VPP)
• Only B decay tested
• UML
• Isobar model
• Likelihood goodness-of-fit
• Normalization: phase space MC and several numerical methods
• Normalization calculated for each fit iteration, allowing mass and width fitting
• Efficiency correction: yes
• Fit fractions: account for interference
• Available in BaBar CVS repository: cvs co BToDjFittingTools
  

• Charmless AWG
• 3pi,Kpipi,3K: Laura++
• KKKs: custom
• h+h+h- (h=pi/K): custom
• Kpipi0, rhopi: RhoPiTools