Challenges in Double Beta Decay

Table 7

NEXT-100	^136Xe (𝑄𝛽𝛽 = 2457 keV) under construction
FWHM	12.5 keV
MASS	90 kg of ^136Xe (100 kg of enriched Xe)
BKG
Rejection	Event topology (predicted background rejection ratios are of ∼2 × 10^−7 and detection efficiency of 25%)
Goal	8 × 10^−4 counts/(keV·kg·yr) (evaluation done on the basis of the background budget and rejection factors)
𝐹^0𝜈68%C.L.	1.6 × 10^26 yr in 5 years