Discussing direct search of dark matter particles in the Minimal Supersymmetric extension of the Standard Model with light neutralinos

摘要

We examine the status of light neutralinos in an effective MinimalSupersymmetric extension of the Standard Model (MSSM) at the electroweak scalewhich was considered in the past and discussed in terms of the available dataof direct searches for dark matter (DM) particles. Our reanalysis is promptedby new measurements at the Tevatron and B-factories which might potentiallyprovide significant constraints on the MSSM model. Here we examine in detailall these new data and show that the present published results from theTevatron and B-factories have only a mild effect on the original lightneutralino population. This population, which fits quite well the DAMA/LIBRAannual modulation data, would also agree with the preliminary results of CDMS,CoGeNT and CRESST, should these data, which are at present only hints orexcesses of events over the expected backgrounds, be interpreted as authenticsignals of DM. For the neutralino mass we find a lower bound of 7-8 GeV. Ourresults differ from some recent conclusions by other authors because of a fewcrucial points which we try to single out and elucidate.