From Twistor-Particle Models to Massive Amplitudes

In his twistor-particle programme of the 1970's, Roger Penrose introduced a representation massive particle phase space in terms pair twistors subject to an internal symmetry group. Here we use this introduce chiral string whose target is complexification space, extended so as incorporate supersymmetry. We show that gauge anomalies associated group vanish only for maximal supersymmetry, and correlators these models describe amplitudes involving particles with manifest The amplitude formulae exhibit double copy structure from theory on Coulomb branch gravity, although graviton remains massless. are closely related those obtained earlier by authors expressed polarised scattering equations.