Thermodynamic inclusive single particle spectra and particle production ratios at the ISR

Two essential modifications of the thermodynamic single particle spectra using fireballs according to the strong bootstrap model are described: (i) An energy-dependent velocity weight function is introduced which leads to better agreement with the flat single particle spectra in the central region observed at the ISR. (ii) Heavy pair production is modified by producing the two particles in different steps of the decay chain of the fireballs. The fact that heavy fireballs are produced leads in the model to a natural understanding of the deviations from scaling behaviour in the central region of single particle spectra p + p → π^+-, p role=presentation style=font-size: 90%; display: inline-block; position: relative;>$\text{p}$$\text{p}$ or K⁻ + anything between 20 GeV and ISR energies. The particle production ratios p role=presentation style=font-size: 90%; display: inline-block; position: relative;>$\text{p}$$\text{p}$/π⁻, K⁻/π⁻, π⁺/p, K⁺/p and p role=presentation style=font-size: 90%; display: inline-block; position: relative;>$\text{p}$$\text{p}$/p are compared to recent ISR data.