2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/197243The relic abundance and the scalar cross-section off nucleon for light neutralinos (of mass below about 45 GeV) are evaluated in an effective MSSM model without GUT-inspired relations among gaugino masses. It is shown that these neutralinos may provide a sizeable contribution to the matter density in the Universe and produce measurable effects in WIMP direct detection experiments. These properties are elucidated in terms of simple analytical arguments.11 pages, 4 figures, typeset with ReVTeX4. The paper may also be found at http://www.to.infn.it/~fornengo/papers/light.ps.gz Some comments and references addedHigh Energy Physics - PhenomenologyAstrophysicsHigh Energy Physics - Experimenttext