Details

Autor(en) / Beteiligte

• Aguilar-Arevalo, A.
• Amidei, D.
• Baxter, D.
• Cancelo, G.
• Cervantes Vergara, B.A.
• Chavarria, A.E.
• Darragh-Ford, E.
• D'Olivo, J.C.
• Estrada, J.
• Favela-Perez, F.
• Gaïor, R.
• Guardincerri, Y.
• Hossbach, T.W.
• Kilminster, B.
• Lawson, I.
• Lee, S.J.
• Letessier-Selvon, A.
• Matalon, A.
• Mitra, P.
• Piers, A.
• Privitera, P.
• Ramanathan, K.
• Da Rocha, J.
• Sarkis, Y.
• Settimo, M.
• Smida, R.
• Thomas, R.
• Tiffenberg, J.
• Traina, M.
• Vilar, R.
• Virto, A.L.

Titel

Measurement of the bulk radioactive contamination of detector-grade silicon with DAMIC at SNOLAB

Ist Teil von

• Journal of instrumentation, 2021-06, Vol.16 (6), p.P06019

Ort / Verlag

Bristol: IOP Publishing

Erscheinungsjahr

2021

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Abstract We present measurements of bulk radiocontaminants in the high-resistivity silicon CCDs from the DAMIC experiment at SNOLAB. We utilize the exquisite spatial resolution of CCDs to discriminate between α and β decays, and to search with high efficiency for the spatially-correlated decays of various radioisotope sequences. Using spatially-correlated β decays, we measure a bulk radioactive contamination of 32 Si in the CCDs of 140 ± 30 μBq/kg, and place an upper limit on bulk 210 Pb of < 160 μBq/kg. Using similar analyses of spatially-correlated α and β decays, we set upper limits of < 11 μBq/kg (0.9 ppt) on 238 U and < 7.3 μBq/kg (1.8 ppt) on 232 Th in the bulk silicon. The ability of DAMIC CCDs to identify and reject spatially-coincident backgrounds, particularly from 32 Si, has significant implications for the next generation of silicon-based dark matter experiments, where β's from 32 Si decay will likely be a dominant background.