DOUBLE BETA DECAY AND BEYOND STANDARD MODEL PARTICLE PHYSICS

2011 ◽  
Author(s):  
HANS V. KLAPDOR-KLEINGROTHAUS ◽  
IRINA V. KRIVOSHEINA
Keyword(s):  
Beyond Standard Model ◽  
Standard Model ◽  
Beta Decay ◽  
Particle Physics ◽  
Double Beta Decay ◽  
Standard Model Particle ◽  
Model Particle

scholarly journals Shell Model Studies of Competing Mechanisms to the Neutrinoless Double-Beta Decay in 124Sn, 130Te, and 136Xe

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Andrei Neacsu ◽  
Mihai Horoi
Keyword(s):  
Beyond Standard Model ◽  
Standard Model ◽  
Shell Model ◽  
Beta Decay ◽  
Neutrinoless Double Beta Decay ◽  
Mass Scale ◽  
Double Beta Decay ◽  
Majorana Fermion ◽  
Mass Hierarchy ◽  
Model Studies

Neutrinoless double-beta decay is a predicted beyond Standard Model process that could clarify some of the not yet known neutrino properties, such as the mass scale, the mass hierarchy, and its nature as a Dirac or Majorana fermion. Should this transition be observed, there are still challenges in understanding the underlying contributing mechanisms. We perform a detailed shell model investigation of several beyond Standard Model mechanisms that consider the existence of right-handed currents. Our analysis presents different venues that can be used to identify the dominant mechanisms for nuclei of experimental interest in the mass A~130 region (124Sn, 130Te, and 136Xe). It requires accurate knowledge of nine nuclear matrix elements that we calculate in addition to the associated energy-dependent phase space factors.

FROM NUCLEAR PHYSICS TO PHYSICS BEYOND THE STANDARD MODEL: FIRST EVIDENCE FOR LEPTON NUMBER VIOLATION AND THE MAJORANA CHARACTER OF NEUTRINOS

2004 ◽  
Vol 13 (10) ◽  
pp. 2107-2126 ◽  
Author(s):  
H. V. KLAPDOR-KLEINGROTHAUS
Keyword(s):  
Beyond Standard Model ◽  
Standard Model ◽  
Beta Decay ◽  
Neutrino Mass ◽  
Half Life ◽  
Nuclear Physics ◽  
High Energy ◽  
Lepton Number ◽  
Double Beta Decay ◽  
Boson Mass

Nuclear double beta decay provides an extraordinarily broad potential to search for beyond-standard-model physics. The occurrence of the neutrinoless decay(0νββ) mode has fundamental consequences: first, the total lepton number is not conserved, and second, the neutrino is a Majorana particle. Furthermore, the measured effective mass provides an absolute scale of the neutrino mass spectrum. In addition, double beta experiments yield sharp restrictions for other beyond-standard-model physics. These include SUSY models (R-parity breaking and conserving), leptoquarks (leptoquark-Higgs coupling), compositeness, left-right symmetric models (right-handed W boson mass), test of special relativity and of the equivalence principle in the neutrino sector and others. First evidence for neutrinoless double beta decay was reported by the HEIDELBERG–MOSCOW experiment in 2001. The HEIDELBERG–MOSCOW experiment is by far the most sensitive0νββ experiment since more than 10 years. It is operating 11 kg of enriched 76Ge in the GRAN SASSO Underground Laboratory. The analysis of the data taken from 2 August 1990–20 May 2003 is presented here. The collected statistics is 71.7 kg y. The background achieved in the energy region of the Q value for double beta decay is 0.11 events/kg y keV. The two-neutrino accompanied half-life is determined on the basis of more than 100,000 events to be [Formula: see text] years. The confidence level for the neutrinoless signal has been improved to a 4.2σ level. The half-life is [Formula: see text] years. The effective neutrino mass deduced is (0.2–0.6) eV (99.73% C.L.), with the consequence that neutrinos have degenerate masses. The sharp boundaries for other beyond SM physics, mentioned above, are comfortably competitive to the corresponding results from high-energy accelerators like TEVATRON, HERA, etc.

scholarly journals What Is Matter According to Particle Physics, and Why Try to Observe Its Creation in a Lab?

Universe ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. 61
Author(s):  
Francesco Vissani
Keyword(s):  
Standard Model ◽  
Conservation Laws ◽  
Beta Decay ◽  
Particle Physics ◽  
Neutrinoless Double Beta Decay ◽  
Lepton Number ◽  
Double Beta Decay ◽  
Nuclear Process ◽  
The Standard Model ◽  
Technical Considerations

The standard model of elementary interactions has long qualified as a theory of matter, in which the postulated conservation laws (one baryonic and three leptonic) acquire theoretical meaning. However, recent observations of lepton number violations—neutrino oscillations—demonstrate its incompleteness. We discuss why these considerations suggest the correctness of Ettore Majorana’s ideas on the nature of neutrino mass and add further interest to the search for an ultra-rare nuclear process in which two particles of matter (electrons) are created, commonly called neutrinoless double beta decay. The approach of the discussion is mainly historical, and its character is introductory. Some technical considerations, which highlight the usefulness of Majorana’s representation of gamma matrices, are presented in the appendix.

scholarly journals Neutrinoless Double-Beta Decay

2012 ◽  
Vol 2012 ◽  
pp. 1-38 ◽  
Author(s):  
Andrea Giuliani ◽  
Alfredo Poves
Keyword(s):  
Beta Decay ◽  
Particle Physics ◽  
Nuclear Physics ◽  
Experimental Situation ◽  
Neutrinoless Double Beta Decay ◽  
Majorana Neutrino ◽  
Double Beta Decay ◽  
Point Of View ◽  
The Status ◽  
Majorana Neutrino Mass

This paper introduces the neutrinoless double-beta decay (the rarest nuclear weak process) and describes the status of the research for this transition, both from the point of view of theoretical nuclear physics and in terms of the present and future experimental scenarios. Implications of this phenomenon on crucial aspects of particle physics are briefly discussed. The calculations of the nuclear matrix elements in case of mass mechanisms are reviewed, and a range for these quantities is proposed for the most appealing candidates. After introducing general experimental concepts—such as the choice of the best candidates, the different proposed technological approaches, and the sensitivity—we make the point on the experimental situation. Searches running or in preparation are described, providing an organic presentation which picks up similarities and differences. A critical comparison of the adopted technologies and of their physics reach (in terms of sensitivity to the effective Majorana neutrino mass) is performed. As a conclusion, we try to envisage what we expect round the corner and at a longer time scale.

scholarly journals NEUTRINO-LESS DOUBLE BETA DECAY AND PARTICLE PHYSICS

2011 ◽  
Vol 20 (09) ◽  
pp. 1833-1930 ◽  
Author(s):  
WERNER RODEJOHANN
Keyword(s):  
Beta Decay ◽  
Particle Physics ◽  
Nuclear Physics ◽  
Double Beta Decay ◽  
Standard Interpretation ◽  
Sterile Neutrinos ◽  
Physics Potential ◽  
Majorana Neutrinos ◽  
Alternative Processes ◽  
Extensive List

We review the particle physics aspects of neutrino-less double beta decay. This process can be mediated by light massive Majorana neutrinos (standard interpretation) or by something else (non-standard interpretations). The physics potential of both interpretations is summarized and the consequences of future measurements or improved limits on the half-life of neutrino-less double beta decay are discussed. We try to cover all proposed alternative realizations of the decay, including light sterile neutrinos, supersymmetric or left-right symmetric theories, Majorons, and other exotic possibilities. Ways to distinguish the mechanisms from one another are discussed. Experimental and nuclear physics aspects are also briefly touched, alternative processes to double beta decay are discussed, and an extensive list of references is provided.

Sign in / Sign up

Export Citation Format

Share Document