计算双通道散射BUBBLEGUM v.2 的源代码-The FORTRAN code BUBBLEGUM.f calculates the unitary, analytic T-matrix for a two-channel problem with an arbitrary number of resonances. It also gives the approximate results from the K-matrix method, the Breit-Wigner approximation, or the perturbative method for the same problem.

The FORTRAN code EPLOT.f generates a standard eps figure "plot.eps" from the data files generated by BUBBLEGUM.f. It allows one to include and exclude certain data files.

The Coherent Bubble Sum Approximation (hence the name "bubblegum") which is used to determine the exact T-matrix is explained in the paper bubblegum.ps (bubblegum.pdf).

Three key features of bubblegum, which are absent in most coupled channel codes:

ANALYTICITY AND UNITARITY

MASS SHIFTS DIRECTLY CORRELATED WITH THE HADRONIC FORM FACTORS

EXPANSION FOR THE FORM FACTORS　ALLOWS ONE TO FIT THE FORM FACTORS FROM THE DATA