/x3872cohbkg

Toys for coherent background in X(3872) -> J/psi pi+ pi-

Primary LanguagePython

x3872cohbkg

A toy model for X(3872) -> J/psi pi+ pi- with coherenct background. Invariant mass m(J/psi pi+ pi-) is considered. The X(3872) lineshape is described with a relativistic Breit-Wigner. Backgound is divided into coherennt and non-coherent parts. Coherent background is described with 1st order polynomial, while non-coherent background is described with 2nd order polynomial. Detector resolution is described with Gaussian.

The model parameters are:

  1. X(3872) mass
  2. X(3872) width
  3. fraction of coherent background
  4. phase of coherent background
  5. fraction of non-coherent background
  6. width of the Gaussian (detector resolution)
  7. polynomial coefficient for coherent background lineshape 8 and 9. two polynomial coefficients for non-coherent background lineshape

Dependences:

  • scipy: numpy and matplotlib
  • iminuit

Content:

  • lineshapes.py contains model definition and model parameters
  • plots.py contains a number of ploting functions
  • toymc.py runs toy MC generation
  • fitter.py runs toy MC generation and then fitting with different models
  • interactive_model.py runs interactive lineshape visualization