Year: 2002
Type: article
Abstract: We study the pseudo-Dirac mixing of left- and right-handed neutrinos in the case where the Majorana masses M L and M R are small when compared with the Dirac mass, M D . The light Majorana masses could be generated by a non-renormalizable operator reflecting effects of new physics at some high energy scale. In this context, we obtain a simple model independent closed bound for M D . A phenomenologically consistent scenario is achieved with M L ,M R ≃10−7 eV and M D ≃10−5–10−4 eV. This precludes the possibility of positive mass searches in the planned future experiments like GENIUS or in tritium decay experiments. If on the other hand, GENIUS does observe a positive signal for a Majorana mass ⩾10−3 eV, then with very little fine tuning of neutrino parameters, the scale of new physics could be in the TeV range, but pseudo-Dirac scenario in that case is excluded. We briefly discuss the constraints from cosmology when a fraction of the dark matter is composed of nearly degenerate neutrinos.
Source: Physics Letters B
Authors: K.R.S. Balaji, Anna Kalliomäki, Jukka Maalampi
Language: English
Topic: Neutrino Physics Research
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid:
OpenAlex ID: W2003610505