Related papers: Decomposition of $d=9$ short-range $0\nu\beta\beta…
We study the systematical one-loop decomposition of the dimension-7 long-range $0\nu\beta\beta$ decay operators. We find that there are 3 genuine one-loop topologies and 8 diagrams. The procedure to determine the SM quantum number…
For Majorana neutrino masses the lowest dimensional operator possible is the Weinberg operator at $d=5$. Here we discuss the possibility that neutrino masses originate from higher dimensional operators. Specifically, we consider all…
Neutrinoless double beta decay ($0\nu\beta\beta$) may receive sizable contributions from short-range physics beyond the Standard Model. We present a systematical classification of all tree-level ultraviolet completions of the dimension-11…
We discuss the generation of small neutrino masses from d=7 1-loop diagrams. We first systematically analyze all possible d=7 1-loop topologies. There is a total of 48 topologies, but only 8 of these can lead to "genuine" d=7 neutrino…
We discuss the systematic decomposition of all dimension-7 (d=7) lepton number violating operators. These d=7 operators produce momentum enhanced contributions to the long-range part of the neutrinoless double beta decay amplitude and thus…
We study the systematic decomposition of the dimension nine neutron-antineutron oscillation operators at tree and one-loop levels. We discuss the topologies' generation and the assignment of the chiral quarks. The completed lists of the…
We discuss the systematic decomposition of the dimension nine neutrinoless double beta decay operator, focusing on mechanisms with potentially small contributions to neutrino mass, while being accessible at the LHC. We first provide a (d=9…
We carry out a systematic investigation for the minimal Dirac neutrino mass models emerging from generic one-loop and two-loop topologies that arise from $d=5$ effective operator with a singlet scalar, $\sigma$. To ensure that the…
Neutrinoless double beta decay can significantly help to shed light on the issue of non-zero neutrino mass, as observation of this lepton number violating process would imply neutrinos are Majorana particles. However, the underlying…
The decay rate of neutrinoless double beta ($0\nu\beta\beta$) decay contains terms from heavy particle exchange, which lead to dimension-9 (d=9) six fermion operators at low energies. Limits on the coefficients of these operators have been…
We present a classification of SU(3) x SU(2) x U(1) gauge invariant \Delta L = 2 (L being lepton number) effective operators relevant for generating small Majorana neutrino masses. Operators of dimension up to 11 have been included in our…
We systematically analyze the $d=5$ Weinberg operator at 2-loop order. Using a diagrammatic approach, we identify two different interesting categories of neutrino mass models: (i) Genuine 2-loop models for which both, tree-level and 1-loop…
We perform a systematic study of lepton-number-violating (LNV) dimension-9 operators in the Standard Model Effective Field Theory (SMEFT) that can mediate neutrinoless double beta decay ($0\nu\beta\beta$) at tree level, and map them to…
Neutrinoless double beta ($0\nu\beta\beta$) decay is the most promising way to determine whether neutrinos are Majorana particles. There are many experiments based on different isotopes searching for $0\nu\beta\beta$ decay. Combining the…
Effective operators relevant for generating small Majorana masses for the neutrinos in the Standard Model will be considered. These operators serve as a useful guide for building models of neutrino mass. Some of these operators are…
In this paper, we investigate minimal scalar leptoquark models that dynamically generate neutrino Majorana masses at the one-loop level and examine their implications for low-energy processes. We show that these models can produce viable…
We perform a systematic study of the $d=5$ Weinberg operator at the one-loop level. We identify three different categories of neutrino mass generation: (1) finite irreducible diagrams; (2) finite extensions of the usual seesaw mechanisms at…
We study systematically the decomposition of the Weinberg operator at three-loop order. There are more than four thousand connected topologies. However, the vast majority of these are infinite corrections to lower order neutrino mass…
Neutrinoless double beta decay ($0\nu\beta\beta$) is a crucial test for lepton number violation. Observation of this process would have fundamental implications for neutrino physics, theories beyond the Standard Model and cosmology.…
We study the models with the Majorana neutrino masses generated radiatively by two-loop diagrams due to the Yukawa $\rho \bar \ell_R^c \ell_R$ and effective $\rho^{\pm\pm} W^\mp W^\mp$ couplings along with a scalar triplet $\Delta$, where…