Search for stable hadronizing squarks and gluinos in e + e − collisions up to √ s = 209 GeV

Searches for stable, hadronizing scalar quarks and gluinos are performed using the data collected with the ALEPH detector at LEP. Gluon splitting into a gluino or a squark pair is searched for at centre-of-mass energies around the Z resonance, in the e + e − → q¯q˜g˜g and q¯q˜q¯˜q processes. Stable squark pair production, and stop pair production with subsequent decays into a stable gluino, ˜t → c˜g, are also directly searched for at centre-of-mass energies from 183 to 209 GeV. Altogether, stable hadronizing stop (sbottom) quarks are excluded up to masses of 95 (92) GeV /c 2 , and stable hadronizing gluinos are excluded up to 26.9 GeV /c 2 , at 95% confidence level. In the framework of R-parity-conserving supersymmetric models in which the gluino and the stop quark are the two lightest supersymmetric particles, a 95% C.L. lower limit of 80 GeV /c 2 is set on the stop quark mass.