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arXiv · 0705.1503

Insensitivity of flavoured leptogenesis to low energy CP violation

Sacha Davidson·Julia Garayoa·Federica Palorini·Nuria Rius
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Abstract

If the baryon asymmetry of the Universe is produced by leptogenesis, CP violation is required in the lepton sector. In the seesaw extension of the Standard Model with three hierarchical right-handed neutrinos, we show that the baryon asymmetry is insensitive to the PMNS phases: thermal leptogenesis can work for any value of the observable phases. This result was well-known when there are no flavour effects in leptogenesis; we show that it remains true when flavour effects are included.

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Sacha Davidson, Julia Garayoa, Federica Palorini, Nuria Rius. 2007-10-15. Insensitivity of flavoured leptogenesis to low energy CP violation. https://doi.org/10.1103/physrevlett.99.161801

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