Dear Florian,

I am trying to implement a left-right symmetric universal seesaw model in SARAH with extra singlet fermions to generate SM fermion masses. I am having problems mainly with the neutrino sector. The left-handed and right-handed neutrinos arising from the doublets are light and equal in mass (forming pseudo-Dirac like state) while the heavy singlet neutrinos (N_L, N_R) may or may not be degenerate. Is it possible to implement such a model where the the light neutrinos are Dirac-like while the heavy ones are Majorana-like? I will be very thankful if you please let me know how to implement such a model, if possible.

Thanks a lot.

Regards,
Ayon

Hi,

there shouldn't be any problem with keeping all Neutrinos as Majorana states. (That's actually also the only possibility which I see)

Cheers
Florian