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# A new Littlest Seesaw model

Chen, Ping-Tao, Ding, Gui-Jun, King, Stephen and Li, Cai-Chang (2020) A new Littlest Seesaw model. Journal of Physics G: Nuclear and Particle Physics, 47 (6), [065001].

Record type: Article

## Abstract

We propose and discuss a new Littlest Seesaw model, realized in the tri-direct CP approach, in which the couplings of the two right-handed neutrinos to the lepton doublets are proportional to (0, −1, 1) and (1,5/2, −1/2) respectively with the relative phase η = −π/2. This model can give an excellent description of lepton flavour mixing, including an atmospheric neutrino mixing angle in the second octant, in terms of only two input parameters. We show that the observed baryon asymmetry can be generated for the lightest right-handed neutrino mass M 1 = 1.176 × 1011 GeV in SM and M 1 = 3.992 × 1010 GeV in MSSM with $\tan \beta =5$. We construct an explicit Littlest Seesaw model based on the flavour symmetry S 4 × Z 5 × Z 8 in which the desired alignments and the phase η = −π/2 are achieved.

Text
A new Littlest Seesaw model - Accepted Manuscript

Accepted/In Press date: 10 March 2020
e-pub ahead of print date: 9 April 2020
Keywords: CP violation, discrete symmetries, model building, neutrino physics

## Identifiers

Local EPrints ID: 440999
URI: http://eprints.soton.ac.uk/id/eprint/440999
ISSN: 0954-3899
PURE UUID: 3e3636a2-94cc-4110-9324-8a19c2875f53

## Catalogue record

Date deposited: 27 May 2020 16:53

## Contributors

Author: Ping-Tao Chen
Author: Gui-Jun Ding
Author: Stephen King
Author: Cai-Chang Li