Search for β+/EC double beta decay of 120Te

Abstract

a b s t r a c tWe present a search for b + /EC double beta decay of 120 Te performed with the CUORICINO experiment, an array of TeO 2 cryogenic bolometers. After collecting 0.0573 kg Á y of 120 Te, we see no evidence of a signal and therefore set the following limits on the half-life: T 0m 1=2 > 1:9 Á 10 21 y at 90% C.L. for the 0m mode and T 2m 1=2 > 7:6 Á 10 19 y at 90% C.L. for the 2m mode. These results improve the existing limits by almost three orders of magnitude (four in the case of 0m mode).

Search for double-βdecay processes in106Cd with the help of a106CdWOBelli1, Bernabei2, Boiko3 et al. 2012Phys. Rev. C

“…The results of the searches for the capture of two electrons from atomic shells (2ε), electron capture with positron emission (εβ + ), and emission of two positrons (2β + ) are at the level of 10 16 -10 21 yr (see review [2] and original works [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27]); although allowed, the two-neutrino mode of these processes has not yet been detected. 1 High-sensitivity experiments to search for neutrinoless 2ε and εβ + decays are also important because they could clarify a contribution of right-handed admixtures in weak interactions [31].…”

Search for neutrinoless β+EC decay of Te120 with CUORE-0

“…Using the most recent evaluation of the 120 Te natural abundance, f 120 = 0.09(1)% [15], the 120 Te mass contained in CUORE-0 is 28 g, corresponding to 1.3 × 10 23 atoms of 120 Te. We note that this value of f 120 differs from the 0.096(2)% used by Cuoricino [21], which was taken from Ref. [28].…”

“…[21], was obtained by Cuoricino [22]. The exposure of CUORE-0 is just about half of the Cuoricino one; however, the lower background and higher signal efficiency lead to a higher sensitivity.…”

“…We describe a new analysis method for the simultaneous fit of signatures with different event topology, and of data subsets with different signal efficiency, obtaining a limit on the half-life of the decay of T 1/2 > 1.6 × 10 21 yr at 90% credibility interval (CI). Combining this with results from Cuoricino, a predecessor experiment, we obtain the strongest limit to date, corresponding to T 1/2 > 2.7 × 10 21 yr at 90% CI.…”

A measurement of the 2 neutrino double beta decay rate of Te-130 in the CUORICINO experiment

“…CUORICINO was intended as a prototype detector for the Cryogenic Underground Observatory for Rare Events (CUORE), but was also a sensitive physics experiment on its own. Although the primary aim of CUORI-CINO was to search for 0νββ of 130 Te, the detector was also used to search for other kinds of rare events, such as dark matter interactions, 2νββ, and other rare nuclear processes ( [77], [78]). …”