Gravitino Problem

I start here with the wiki page of Gravitino. We want to have a low energy SM particle emitted in the late decay of NLSP to the LSP. Let us first distinguish two different cases:

1. Gravitino is the LSP
2. Gravitino is the NLSP

1. Correct dark matter abundance of the LSP both from NLSP decays and from LSP decoupling.
2. Nucleosynthesis constraints on the energy release from NLSP decay.
3. Constraints from the CMB on high-energy photons for gravitino lifetimes larger than 10^(12) seconds.

Furthermore, we are, initially, in a CMSSM context and there are some relations among masses of gauginos and sfermions that we can use.

-- OscarVives - 11 May 2009

• Degenerate.ps: Constraints from BBN and CMB

• Degenerate.ps: typo corrected and include Gravitino as LSP section

OK, I comment here the notes by Ki Young. I think they are really nice and very clear. I like the definition of delta and omega, they are very useful for the discusion. Yesterday I was wondering what had happened in the second plot with the YX, but now it is very elegantly incorporated with omega.

Just for the numbers, I was trying to get Eq(5) and my question is whether YLSP = nLSP/s or nLSP/ngamma.

Section 2 is very clear and the plots cna be easily understood.

In the gravitino LSP scenario, looks at the moment as the best option because we can have delta = 10^(-2) and omega = 10^(-2). Then we could be in the "correct" range of lifetimes, I guess from 10^(10) to 10^(12). We have to add the lifetime formula. From my experience I think this is perfectly possible in the CMSSM, because in the neutralino NLSP, all the region below the coannihilation has smaller DM abundance than needed, and in the degenerate stau-neutralino limit should be really very small. I expect to cross continuosly (wrt DM abundance) to the stau NSLP region. The problem is, if I remember correctly in the stau NLSP with the bound state constraints. Then we have a multiple degeneracy requirement stau-neutralino-gravitino...

-- OscarVives - 14 May 2009

Checking if the WebNotify works correctly

-- OscarVives - 02 Jun 2009

• BH1.eps: BH1.eps