The effective Regge trajectory, ~aeff(t), for a given t is de-Chew-Frautschi Plot, Least-squares. termined by first interpolating the experimental do/dt to obtain values at the same t-but different s-values (where s is the square of the c.m. energy and -t is the square of the 4-Nature of physical problem momentum transfer). The aeff is then calculated by perform-Regge theory forms the basis of most of the current at-ing a least-squares fit of ~n(da/dt) to Qn s. Several t-values are tempts to understand the strong interactions of elementary fitted simultaneously so that the normalization of an experiparticles. Consequently as a preliminary to any serious analy-ment at a given s-value may be determined. Further, for a sis of high-energy data for two-body reactions it is desirable given energy, Qn(da/dt) can be parametrised by a polynomial to extract the effective Regge trajectory from the differential in t of degree specified by the user, and a least-squares fit is cross section (do/dt) data for each reaction under study. A pro-used to calculate the parameters from the experimental data. gram has therefore been written to calculate these effective trajectories from the data. The program includes the option of Restrictions on the complexity of the problem determining the t-independent overall normalization of a given A maximum of six different reacti6ns may be analysed experiment, and it calculates the slope of the differential cross in one run. For each reaction do/dt data can be used at up to section, and the integrated cross section. 20 different momenta, and ~eff can be calculated at up to 20 different t-values. Typical running time * Work supported by the Science Research Council. About eight seconds to calculate aeff at six t-values using da/dt data at eight different momenta. * * .554E 00 * X* ('.5408 0(' * * (.544E00 * * (.5395 V * P D.5342 0" * -* 1'.529E or, * -* 0.5245 ~r 'P * 1.5195 00 * ".5145 C') * * 0.5 95 (1 * * D.54E OC * A * 10 * * .4945 0') * * ~.489E ('0 * * .4845 00 * -* '.479E 0(' * * '.474E CD * -* (.469E 1r * * 4645 CC * * '.4505 (1 * * .4545 '~D * * '4498 CI' * X * (4445 0" * * .439EC' *-* (.434E ('0 * * ~.429F C" * * (.4245 00 * --* .4IgE C) * * '414E~.' * * (.4 9E CC