SUSY-GUTs, SUSY-Seesaw and the Neutralino Dark Matter

Understand

We will consider a SUSY-SU(5) with one right-handed neutrino with a large top like Yukawa coupling.

• Assuming universal soft masses at high scale we compute the low-energy spectrum and subsequently the neutralino LSP relic density taking also into consideration SU(5) as well as the see-saw running effects above the gauge coupling unification scale.
• We found that there exists no viable region in parameter space for $\tan\beta \ler ~35$.
• The $\tilde{\tau}$ coannihilation process starts becoming efficient for $\tan\beta \ger 35-40$.