Analysis around Q ββ for 76 Ge Double Beta Decay experiments , and Statistics at Low Count Rates
نویسندگان
چکیده
The background in the region of the Q-value for neutrinoless double beta decay of Ge has been investigated by different methods: Simulation with GEANT 4 of the HEIDELBERG-MOSCOW experiment, analysis of other Ge double beta experiments. Statistical features of the analysis at very low count rates are discussed.
منابع مشابه
Majorons from Double Beta Decay *
We explain the existence of excess events near the endpoints of the double beta decay (ββ) spectra of several elements, using the neutrinoless emission of massless Goldstone bosons. Models with scalars carrying lepton number −2 are proposed for this purpose so that ordinary neutrinoless ββ is forbidden, and we can raise the scale of global symmetry breaking above the 10 keV scale needed for obs...
متن کاملExact evaluation of the nuclear form factor for new kinds of majoron emission in neutrinoless double beta decay ∗
We have developed a formalism, based on the Fourier-Bessel expansion, that facilitates the evaluation of matrix elements involving nucleon recoil operators, such as appear in serveral exotic forms of neutrinoless double beta decay (ββ 0ν). The method is illustrated by applying it to the " charged " majoron model, which is one of the few that can hope to produce an observable effect. From our nu...
متن کاملDouble Beta Decay: Theory, Experiment, and Implications
Double beta decay is a rare spontaneous nuclear transition in which the nuclear charge changes by two units while the mass number remains the same. It has been long recognized as a powerful tool to study lepton number conservation in general, and neutrino properties in particular. Since the lifetimes of double beta decays are so long, the experiments on double beta decay are very challenging an...
متن کاملCharged Majoron Emission in Neutrinoless Double Beta Decay *
We examine in detail the predictions of the charged majoron model, introduced recently by Burgess and Cline, for 0 + → 0 + ββ transitions. The relevant nuclear matrix elements are evaluated, within the quasiparticle random phase approximation, for 76 Ge, 128 Te and 150 Nd nuclei. The calculated transition rates turn out to be much smaller than the experimental upper limits on possible majoron e...
متن کاملNeutrinoless Double Beta Decay Constraints∗
A brief overview is given of theoretical analyses with neutrinoless double beta decay experiments. Theoretical bounds on the “observable”, 〈m〉ββ , are presented. By using experimental bounds on 〈m〉ββ , allowed regions are obtained on the ml-cos 2θ12 plane, where ml stands for the lightest neutrino mass. It is shown that Majorana neutrinos can be excluded by combining possible results of future ...
متن کامل