PAWIAN PWA Software
alysis Software) is a partial wave analysis software package with the aim to support analyses dedicated to all physics cases at PANDA and partly to specific items at other hadron spectroscopy experiments. Real data originated from the pbar p annihilation processes and from the e+ e- reactions are currently under investigation with PAWIAN. Essential parts of the powerful, user-friendly and highly modular software are already available. It is possible to define complicated decay trees, to choose different spin formalisms and dynamics as well as to set up numerous other parameters via a simple configuration file without modifying and compiling any code. The key features of PAWIAN which can be setup via such a configuration file with a user-friendly syntax are as follows:
- The amplitudes can be described with different formalisms. The widely-used helicity, canonical and the Lorentz-invariant Rarita-Schwinger formalisms are supported so far.
- A couple of different descriptions of the dynamics can be chosen which are among other things the Breit-Wigner parametrization with or without barrier factors, the FlattÃ©-formalism and the K-matrix formalism.
- The minimization is realized with an event-based maximum likelihood fit. It makes use of the MINUIT2 minimization package. In addition one can start with a pre-fitter based on generic algorithms.
- To improve the performance for the very time-consuming fit procedure the applications can be run in parallel on multi-core CPUs and/or on computer clusters.
- Coupled channel analyses are supported.
- The analyst can generate events based on the user-defined decay model or on the fit result obtained with real data.
- Tools for quality assurance, histogramming and for extracting values of different goodness-of-fit criteria are also available.
PAWIAN is written in C++ and follows an object-oriented approach with a wide range of flexibility. This software code ensures therefore to easily add further decay models, complete amplitudes and also another descriptions for the dynamics.
Outcome of the PAWIAN Activities
- 03 Jul 2014