Moreover, because of the presence of right-handed currents, the exchange of light neutrinos does not necessarily require a chirality violating mass insertion. The effective mass depends thus on 7 out of those 9 physical neutrino parameters: Of these seven parameters, we currently do not know the phases and the lightest mass, where in addition the mass ordering is unknown, i.e. Two quarks in the initial state are converted into a same-sign di-lepton signal and two jets (from [105]). As demonstrated previously, the effect of the color-mismatch arising from loops with gluons linking the quarks from different color-singlet currents participating in the effective operators has a dramatic impact on the predictions for some particular Wilson coefficients. The short-range contribution has been discussed in [87–89]. To answer this question, a comparison of different isotopes and matrix elements is necessary. �"9Qi������*C\u����� & @ Z t � � � � �.Id���� %A^z���� &Ca~����1Om����&Ed����#Cc����'Ij����4Vx���&Il����Ae����@e���� Ek���*Qw���;c���*R{���Gp���@j���>i��� A l � � �! Neutrinoless double beta decay. Double beta decay is a rare second-order process involving the emission of two electrons from a nucleus simultaneously. Many sum-rule examples have been discussed in the literature [50–53]. Updated version (April 2012): Typos corrected, issue with Feynman diagrams solved. Neutrinoless Double Beta Decay: 2015 Review StefanoDell Oro, 1 SimoneMarcocci, 1 MatteoViel, 2,3 andFrancescoVissani 1,4 INFN, Gran Sasso Science Institute, Viale F. Crispi, L Aquila, Italy /Height 588 To discuss such a phenomenon of '0\nu \beta \beta-LHC complementarity' though it is necessary to distinguish between the various mechanisms which may be responsible for the decay. In this section we will discuss various contributions to double beta decay in left–right symmetric models which embed the SM gauge group into an SU(3){}_{c}\otimes SU(2){}_{{\rm{L}}}\otimes SU(2){}_{{\rm{R}}}\otimes U(1){}_{B-{\rm{L}}}. Neutrinoless Double Beta Decay Neutrinoless double beta decay (0νββ) is a very slow lepton-number-violating nuclear transition that occurs if neutrinos have mass (and oscillation experiments tell us they do), and are their own antiparticles, i.e. stream While hunting for this hypothetical nuclear process, a significant amount of two-neutrino double beta decay data have become available. dr. Miha Nemev sek Jo zef Stefan Institute, Ljubljana Ljubljana, February 2017 ... beta decay spectrum in Fig. The most general operator inducing the decay can be parametrized in terms of effective couplings parametrizing interactions which appear point-like at the nuclear Fermi momentum scale (the inverse size of the nucleon) {\mathcal{O}}(100){\rm{MeV}}. Such theories necessarily predict right-handed neutrinos which are included in an SU(2)R doublet as a consequence of the left–right symmetry. �����z���p���g���_���X���Q���K���F���Aǿ�=ȼ�:ɹ�8ʷ�6˶�5̵�5͵�6ζ�7ϸ�9к�܊�ݖ�ޢ�)߯�6��D���S���c���s���� ����2��F���[���p������(��@���X���r������4���P���m��������8���W���w����)���K���m���� C By combining this argument with the results of [75, 76] mentioned above, one can conclude that an observation of short-range 0\nu \beta \beta decay will typically imply that LNV processes should be detected at the LHC as well. (1b) and its Feynman diagram in Fig. For a comparative analysis of all scalar-mediated models based on the SM gauge group see [66]. In [107] it has thus been pointed out that any observation of LNV at the LHC will falsify high-scale leptogenesis. Cosmology yields the best limits in terms of numbers, and can even contribute to the question of mass ordering. To this day, it has not been found. ' �m��o�YOfV�&/oHE�59�\�l�������l%(� F)�BrZA��>zk�e����ɰw�FyF�Wɤ{����_d�DGeUeE�ҮMi�>��b��ތ*����U^5���Kr�wjN�]���� K蟀.��tx�� Q�q�9o!�BT�,��+�G��zR�� j���>�99�ܠ������\ú� 1 0 obj 17 115010, 1 << /S /GoTo /D (subsection.2.1) >> However, in terms of numbers the limits are and will be the weakest, and further improvement beyond 0.1 eV seems impossible. One of the most important open questions in neutrino physics is whether the neutrino is a Majorana fermion. Feynman diagrams for the leading diagrams of neutrinoless double beta decay in left–right symmetric theories: heavy neutrino exchange with right-handed currents, triplet exchange, the λ- and the η-diagram (from left to right). The conventional mechanism is based on the exchange of a massive Majorana neutrino between the two decaying neutrons. Neutrino mixing angle { \theta } _ { 12 } DPG sees itself as particles... Will typically be triggered by a light Majorana neutrino exchange number violating operators thus would if! 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