Results of a search for annual modulation of WIMP signals

A search for particle cold dark matter (CDM) has been carried out at the Canfrane Underground Laboratory (Spain) with a set of three sodium iodide scintillators of 10.7 kg each, during about 2 yr of data taking. The results, corresponding to an exposure of 4613.6 kg day are presented in the form of exclusion plots of the WIMP-target nuclei cross section versus WIMP mass (both Tor spin-independent and spin-dependent WIMP-matter interactions), obtained with the standard method of comparing the observed ate with the expected signal. A distinctive feature of the CDM signal, like: its expected annual modulation, has also been looked for in 1342.8 kg day of data. The nonobservance of such a modulation has been used to draw more stringent exclusion plots than those derived from the standard method.