2021 Impact factor 4.991
Particles and Fields

Eur. Phys. J. C 19, 463-469
DOI: 10.1007/s100520100585

The light Higgs window in the 2HDM at GigaZ

M. Krawczyk1, P. Mättig2 and J. Zochowski3

1  Institute of Theoretical Physics, University of Warsaw, Warsaw, 00-681, Poland
2  Weizmann Institute, Rehovot, Israel
3  Faculty of Physics, Bialystok University, Bialystok, Poland

(Received: 18 September 2000 / Revised version: 22 December 2000 / Published online: 15 March 2001 -© Springer-Verlag 2001)

The sensitivity to a light Higgs boson in the general 2HDM (II), with a mass below 40 GeV, is estimated for a future e+e- Linear Collider operating with a very high luminosity at the Z peak (GigaZ). We consider possible Higgs boson production via the Bjorken process, the (hA) pair production, the Yukawa process $Z\rightarrow b{\bar b}h(A), \rightarrow \tau {\bar \tau}
h(A)$, and the decay $Z{\rightarrow}h(A)+\gamma$. Although the discovery potential is considerably extended compared to the current sensitivities, mainly from LEP, the existence of a h or A even with a mass of a few GeV cannot be excluded with two billion Z decays. The need to study the very light Higgs scenario at a e+e- Linear Collider running at several hundred GeV and the LHC is emphasized.

© Società Italiana di Fisica, Springer-Verlag 2001