In extended supersymmetric models like the N =1 / N =2 hybrid model or the R-symmetric MSSM massive coloured scalar particles that decay into gluons are predicted. These are the scalar partners of a Dirac gluino called scalar gluons (sgluons). Sgluons have positive R-parity and since their coupling to quarks are suppressed by the quark masses, for masses of order 100 GeV sgluons decay mostly to a pair of gluons. Hyperpions from compositeness model have similar properties.

This search is based on the pair production of sgluons each decaying to two gluons, hence this is a four jet (and no missing transverse momentum) topology. Kinematic and topological cuts are used to select the jet pairs compatible with sgluon pair production. The opening angle of the two jets, the reconstructed mass difference of the two jet pairs as well as the production angle of the reconstructed sgluons are used to further purify the sample. The phenomenological study preparing the analysis was done in collaboration with Steffen Schumann (Göttingen University). The most recent results published by ATLAS are based on 4.6 inverse femtobarn at 7 TeV.

ATLAS search for massive coulored scalar particles in four jets.

Group member : Dirk Zerwas (staff)