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Title: Separating $${^{39}\hbox {Ar}}$$ from $${^{40}\hbox {Ar}}$$ by cryogenic distillation with Aria for dark-matter searches
Abstract

Aria is a plant hosting a$${350}\,\hbox {m}$$350mcryogenic isotopic distillation column, the tallest ever built, which is being installed in a mine shaft at Carbosulcis S.p.A., Nuraxi-Figus (SU), Italy. Aria is one of the pillars of the argon dark-matter search experimental program, lead by the Global Argon Dark Matter Collaboration. It was designed to reduce the isotopic abundance of$${^{39}\hbox {Ar}}$$39Arin argon extracted from underground sources, called Underground Argon (UAr), which is used for dark-matter searches. Indeed,$${^{39}\hbox {Ar}}$$39Aris a$$\beta $$β-emitter of cosmogenic origin, whose activity poses background and pile-up concerns in the detectors. In this paper, we discuss the requirements, design, construction, tests, and projected performance of the plant for the isotopic cryogenic distillation of argon. We also present the successful results of the isotopic cryogenic distillation of nitrogen with a prototype plant.

Authors:
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Award ID(s):
1812504 1812472 1622327
Publication Date:
NSF-PAR ID:
10224248
Journal Name:
The European Physical Journal C
Volume:
81
Issue:
4
ISSN:
1434-6044
Publisher:
Springer Science + Business Media
Sponsoring Org:
National Science Foundation
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