The European Physical Journal C - Particles and Fields

, Volume 19, Issue 1, pp 129–136

Hadronic cross-sections in \(\gamma \gamma\) processes and the next Linear Collider


  • R.M. Godbole
    • Centre for Theoretical Studies, Indian Institute of Science, Bangalore 560 012, India
  • G. Pancheri
    • Laboratori Nazionali di Frascati dell'INFN, Via E. Fermi 40, 00044, Frascati, Italy
Theoretical physics

DOI: 10.1007/s100520100549

Cite this article as:
Godbole, R. & Pancheri, G. Eur. Phys. J. C (2001) 19: 129. doi:10.1007/s100520100549


In this note we address the issue of theoretical estimates of the hadronic cross-sections for \(\gamma\gamma\) processes. We compare the predictions of the mini-jet model with data as well as other models, highlighting the band of uncertainties in the theoretical predictions, as well as those in the final values of the \(\sigma (\gamma \gamma \rightarrow{\mathrm{hadrons}}) \) extracted from the data. We find that the rise of \(\sigma_{\gamma \gamma}^{\mathrm{tot}}\) with energy shown in the latest \(\gamma \gamma\) data is in tune with the faster rise expected in the eikonal mini-jet models (EMM). We present an estimate of the accuracy with which this cross-section needs to be measured, in order to distinguish between the different theoretical models which try to “explain” the rise of total cross-sections with energy. We find that the precision of measurement required to distinguish the EMM-type models from the proton-like models, for \( 300 < s^{1/2}_{\gamma \gamma} < 500 \) GeV, is \(\lesssim 20% \), whereas to distinguish between various proton-like models or among the different parametrisations of the EMM, a precision of \(\lesssim 8\)–9% or \(\lesssim 6\)–7%, respectively, is required. We also comment briefly on the implications of these predictions for hadronic backgrounds at the next linear collider (NLC) to be run in the \(\gamma \gamma\) mode or \(e^+e^-\) mode.

Copyright information

© Springer-Verlag Berlin Heidelberg 2001