Double-beta decay investigation with highly pure enriched [Formula: see text]Se for the LUCIFER experiment.
Eur Phys J C Part Fields
; 75: 591, 2015.
Article
in En
| MEDLINE
| ID: mdl-26705394
ABSTRACT
The LUCIFER project aims at deploying the first array of enriched scintillating bolometers for the investigation of neutrinoless double-beta decay of [Formula see text]Se. The matrix which embeds the source is an array of ZnSe crystals, where enriched [Formula see text]Se is used as decay isotope. The radiopurity of the initial components employed for manufacturing crystals, that can be operated as bolometers, is crucial for achieving a null background level in the region of interest for double-beta decay investigations. In this work, we evaluated the radioactive content in 2.5 kg of 96.3 % enriched [Formula see text]Se metal, measured with a high-purity germanium detector at the Gran Sasso deep underground laboratory. The limits on internal contaminations of primordial decay chain elements of [Formula see text]Th, [Formula see text]U and [Formula see text]U are respectively [Formula see text]61, [Formula see text]110 and [Formula see text]74 [Formula see text]Bq/kg at 90 % C.L. The extremely low-background conditions in which the measurement was carried out and the high radiopurity of the [Formula see text]Se allowed us to establish the most stringent lower limits on the half-lives of the double-beta decay of [Formula see text]Se to 0[Formula see text], 2[Formula see text] and 2[Formula see text] excited states of [Formula see text]Kr of 3.4[Formula see text]10[Formula see text], 1.3[Formula see text]10[Formula see text] and 1.0[Formula see text]10[Formula see text] y, respectively, with a 90 % C.L.
Full text:
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Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
Eur Phys J C Part Fields
Year:
2015
Type:
Article