Impact of nuclear spallation process to the Big-Bang nucleosynthesis induced by long lived charged particle Kenichi Sugai (Saitama University) Collaborators Masafumi Koike, Joe Sato,Toshifumi Jittoh (Saitama University) Kazunori Kohri (Tohoku University) Koichi Yazaki (YITP, RIKEN) Masato Yamanaka (ICRR University of Tokyo) Saturday, February, 20,2010;KEK
Contents Introduction Nuclear spallation process of 4 He Summary
Introduction
The Premordial Lithium Problem
New Destruction process of the Lithium 7 Be ( 7 Li) 7 Li ( 7 He) Bound State Model MSSM LSP: Neutralino,NLSP: Stau Long-lived stau due to quasi- degenerate stau-neutralino Internal Conversion Jittoh et al., PRD (2007, 2008)
New Destruction process of the Lithium Over production of 6 Li Model MSSM LSP: Neutralino,NLSP: Stau Long-lived stau due to quasi- degenerate stau-neutralino Internal Conversion Jittoh et al., PRD (2007, 2008) Excessive 6 Li: Catalyzed Fusion Presence of staus enhances the cross section by 10 8 (Pospelov, PRL (2007))
Competing against the Catalyzed Fusion Overproduction of 6 Li due to catalyzed fusion Overproduction of 6 Li Competing process: Nuclear spallation etc. Over production of 6 Li
Competing against the Catalyzed Fusion Competing process: Nuclear spallation etc. Overproduction of 6 Li due to catalyzed fusion Recovery ?
Nuclear Spallation Proceeds Rapidly Catalyzed fusion K.Hamaguchi et al.,PLB650, 268 (2007) at T = 50 keV n( 4 He-stau) > n( 6 Li) at T~(50-100) keV
Nuclear Spallation Proceeds Rapidly Internal conversion, as a reference to the spallation T.Jittoh et al.,Phys.Rev.D78, (2007) Time Scale of Internal Conversion 7 Be ( 7 Li) 7 Li ( 7 He) Bound State << Spallation would outnumber Catalyzed Fusion Stau can’t survive until the BBN era
Motivation Nuclear spallation will dominate catalyzed fusion!! We investigate the spallation processes Applying the result for the BBN with long- lived stau, we show the allowed region for MSSM
Nuclear spallation process of 4 He
Spallation of the 4 He
How to calculate spallation process Forming wave function of nuclear ・ spin and isospin component → antisymmetric for exchange of inner particles ・ space component → symmetric for exchange of inner particles Calculating the amplitude Integrating the square amplitude over all final state’s momentum As a whole, completely antisymmetric for exchange of inner particles
Wave Function of the 4 He Spin and Isospin Component Space Component
Calculation of the Amplitude and the Cross Section Inner Products
Calculation of the Amplitude and the Cross Section Calculation of the Amplitude Calculation of the Cross Section
Time Scale of 4 He Spallation due to Bound Stau ~30MeV Nuclear Spallation dominates Catalyzed Fusion Order of Time Scale of Catalyzed Fusion m stau = 350 GeV Lifetime[s] Deltam[MeV]
Recovery of the Allowed Region Overproduction of 6 Li
Recovery of the Allowed Region Allowed region recovers!! (expectaition) Overproduction of 6 Li
Summary
Spallation process of 4 He suppresses over production of 6 Li caused by the catalyzed fusion. Prediction to the MSSM parameters Calculation applies to X - particles. Calculation of spallation process of 4 He into a deuterium and two neutrons Calculation of spallation process of 7 Li and 7 Be Future works
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Calculation of the Amplitude and the Cross Section Non-relativistic Approximation The Square Amplitude
Calculation of the Amplitude and the Cross Section Calculation of the Cross Section Calculation of the Rate and the Lifetime RateLifetime
Time Scale of 4 He Spallation due to Bound Stau ~30MeV Nuclear Spallation dominates Catalyzed Fusion Order of Time Scale of Catalyzed Fusion m stau = 350 GeV
Calculation of the Amplitude and the Cross Section The Amplitude Calculation