2020 Impact factor 4.590
Particles and Fields
Eur. Phys. J. C 18, 181-193
DOI 10.1007/s100520000520

The $\gamma \gamma \to A^0 A^0 $ process at a $\gamma
\gamma $ collider

G.J. Gounaris - P.I. Porfyriadis

Department of Theoretical Physics, Aristotle University of Thessaloniki, 54006, Thessaloniki, Greece

Received: 12 July 2000 / Published online: 13 November 2000 - © Springer-Verlag 2000

The helicity amplitudes for the process $\gamma \gamma \to A^0 A^0 $ are studied to 1-loop order in the minimal SUSY (MSSM) model, where A0 is the CP-odd Higgs particle. Simple exact analytic formulae are obtained in terms of the C0 and D0 Passarino-Veltman functions, in spite of the fact that the loop diagrams often involve different particles running along their sides. For a usual mSUGRA set of parameters, $\sigma (\gamma \gamma \to A^0 A^0) \sim 0.1$-0.2fb is expected. If SUSY is realized in nature, these expressions should be useful for understanding the Higgs sector.

Copyright Società Italiana di Fisica, Springer-Verlag 2000