Gravitino Dark Matter from Inflaton Decay

Understand

We discuss a scenario that gravitinos produced non-thermally by an inflaton decay constitute dark matter in the present universe.

• We find that this scenario is realized for wide ranges of the inflaton mass and the vacuum expectation value.
• What is intriguing about this scenario is that the gravitino dark matter can have a relatively large free streaming length at matter-radiation equality, which can be probed by future observation on QSO-galaxy strong lens system.