Early tests of scale invariance in high-energy muon scattering

Data are presented on deep inelastic scattering of 56.3- and 150-GeV μ⁺ from an iron target at the Fermi National Acceleratory Laboratory. Observed event rates, averaged over a wide range in ω, are compared to scale-invariance predictions for q² up to 44 (GeV/c)². The ratio of the 150-GeV data to the scale-invariance prediction versus q² is not constant for all accepted ω values. A fit of the form (1+g²/Λ²)⁻² yields a lower limit of Λ>10 GeV with 90% confidence, averaged over a restricted ω range.