SIMPLE Dark Matter Experiment

Welcome to the SIMPLE homepage


The SIMPLE (Superheated Instrument for Massive ParticLe Experiments) dark matter search project is located in a 61mcavern at the 500 level of the Laboratoire Souterrain à Bas Bruit (LSBB) near Apt in southern France.

The project detector, until recently, was based on superheated droplet detectors (SDDs), a suspension of 1%–2% superheated liquid C2ClF5 droplets (~ 30 um radius) in a viscoelastic 900 ml gel matrix which undergo transitions to the gas phase upon energy deposition by incident radiation.

The next phase of SIMPLE involves the transition from SDDs to Bubble Chambers (
C2ClF5 & C3F8), with a re-sitting of the measurements to the LSBB Capsule in order to accommodate a factor 2 increase in the detector neutron shielding thickness.

  • Phase III of SIMPLE in progress...