Extending the CRESST-II commissioning run limits to lower masses

Motivated by the recent interest in light weakly interacting massive particles (WIMPs) of mass ~O(10 GeV/c²), an extension of the elastic, spin-independent, WIMP-nucleon cross-section limits resulting from the CRESST-II commissioning run (2007) are presented. Previously, these data were used to set cross-section limits from 1000 GeV/c² down to ~17 GeV/c², using tungsten recoils, in 47.9 kg-days of exposure of calcium tungstate. Here, the overlap of the oxygen and calcium bands with the acceptance region of the commissioning run data set is reconstructed using previously published quenching factors. The resulting elastic WIMP cross-section limits, accounting for the additional exposure of oxygen and calcium, are presented down to 5 GeV/c².