Properties of hadron final states in e+e− annihilation at 13 GeV and 17 GeV center of mass energies

We have observed e+e− hadrons at C.M. energies of 13 GeV and 17 GeV at PETRA using the TASSO detector. We find R(13 GeV) = 5.6 ± 0.7 and R(17 GeV) = 4.0 ± 0.7. The additional systematic uncertainty is 20%. Comparing inclusive charged hadron spectra we observe scaling between 5 GeV and 17 GeV for x = p/pbeam > 0.2; however the 13 GeV cross section is above the 17 GeV cross section for smaller x. This may be due to copious b production. The events become increasingly jet like at high energies as evidenced by a shrinking sphericity distribution with increasing energy.