The Study Of Partial Wave Analysis Based On The Roofit

The method of partial wave analysis (PWA) is often used in the study of high energy physics experiments, especially it is widely used in the study of the low energy hadron spectroscopy. In high energy physics experiments, experiments directly detected at the end of the stable particles of energy, momentum and charge, and it can not directly detect any information of resonances. And even can’t directly to know whether resonance in the reaction process. Detected physical information directly by experiments should do intensive physical analysis to get information of resonance, and the method of partial wave analysis is a powerful means in physical analysis. Partical Wave Analysis is very important for the physics study at BES. Partial Wave Analysis is a useful tool for extracting physics, such as spin, parity and so on, especially when the effects of interference are important.This paper introduces a new implementation of partial wave analysis based on the RooFit. RooFit is originally designed as a partical physics data analysis tool for BaBar collaboration of the high energy experiment at Stanford Linear Accelerator Center. We take coupled channel of J/ψâ†'φK+K-(φâ†'K+K-) and J/ψâ†'φπ+Ï€-(φâ†'K+K-) as an example to do research. RooFit can make particles analysis language expand to particles analysis language of arbitrary complexity. We develop a toolkit of partial wave analysis for BESâ…¢ partical physics experiment through using the capability of RooFit to handle the probability density function (PDF). We can conveniently construct the PDF of the corresponding physical process by this toolkit of partial wave analysis based on RooFit. This toolkit of partial wave analysis based on RooFit provides various handy functionality of partial wave analysis, such as simultaneous fit of multi channels, background subtraction, calculation of the fitting error of resonance parameters and fraction of decay process, produce plots and generate ’detector Monte Carlo sample’ for various studies. The input and output checks indicate that the toolkit of partial wave analysis software based on RooFit is stable and reliable.