Search for ηb in two-photon collisions at LEP II with the DELPHI detector

The pseudoscalar meson ηb has been searched for in two-photon interactions at LEP II. The data sample corresponds to a total integrated luminosity of 617 pb−1 at centre-of-mass energies ranging from 161 to 209 GeV. Upper limits at a confidence level of 95% on the product Γγγ(ηb)×BR(ηb) are 190, 470 and 660 eV/c2 for the ηb decaying into 4, 6 and 8 charged particles, respectively.