Validation of techniques to mitigate copper surface contamination in CUORE

Validation of techniques to mitigate copper surface contamination in CUORE. Astrop. Phys. 45 (2013), 13-22

In thisarticlewedescribethebackgroundchallengesfortheCUOREexperimentposedbysurfacecon-
tamination ofinertdetectormaterialssuchascopper,andpresentthreetechniquesexploredtomitigate
these backgrounds.Usingdatafromadedicatedtestapparatusconstructedtovalidateandcomparethese
techniqueswedemonstratethatcoppersurfacecontaminationlevelsbetterthan107- 108 Bq/cm2 are
achieved for 238U and 232Th. IftheselevelsarereproducedinthefinalCUOREapparatustheprojected90%
C.L. upperlimitonthenumberofbackgroundcountsintheregionofinterestis0.02–0.03counts/keV/kg/
y dependingontheadoptedmitigationtechnique.