2019 Fiscal Year Annual Research Report
The primordial magnetic field fluctuations, its evolution and the impact on Big-bang nucleosynthesis
| Project/Area Number |
19J22167
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| Research Institution | The University of Tokyo |
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Principal Investigator |
LUO Yudong 東京大学, 理学系研究科, 特別研究員(DC1)
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| Project Period (FY) |
2019-04-25 – 2022-03-31
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| Keywords | Big Bang Nucleosynthesis / Magnetic Field / Screening effect |
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| Outline of Annual Research Achievements |
In this year, we investigated the inhomogeneous magnetic field and the impact on the big bang nucleosynthesis (BBN). The detailed calculation of electron positron thermodynamics is taken into account as well. We evolved the BBN code for each zone and compared the theoretical yields of primordial elements with observations. The result suggests that inhomogeneous PMF can affect theoretical prediction of 7Li abundance significantly. We also investigate the electron screening effect within a background magnetic field. We focus on the weak screening correction in low density relativistic plasma on the electron capture rate. We find an allowed region which satisfies both of D and Yp observational abundance constraints in the BBN model with the screening correction and magnetic field effects.
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| Current Status of Research Progress |
Current Status of Research Progress
1: Research has progressed more than it was originally planned.
Reason
In this year, we investigated the inhomogeneous magnetic field and the impact on the big bang nucleosynthesis (BBN). This study is published on JPS Conference Proceedings, and I was awarded the ANPhA Young Scientist Award because of this result.
We also investigate the electron screening effect within a background magnetic field. We focus on the weak screening correction in low density relativistic plasma on the electron capture rate. This result is published on Phys. Rev. D, 101, 083010 (2020).
I also atteended several international conferences, discussed with many experts in nuclear astrophysics and plasma physics.
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| Strategy for Future Research Activity |
For the future work, our project focus on two folds of the impact from magnetic field on the nuclear astrophysics. For the large scale primordial magnetic field, our next year plan has two steps:
1. Include the time evolution of PMF (fluctuation and dissipation).
2. Encoding the evolution of PMF with BBN nuclear reaction network to provide a systematic BBN calculation involving MHD.
We are also interested in strong magnetic field inside the MHD-Jet Supernovae. For such high density plasma, our future work are:
1. For high temperature regio, we will investigate electron capture reaction rate under the strong background magnetic field, try to constrain the electro fraction in this phase.
2. We will try to obtain the final r-process nucleosynthesis yields with a magnetic field background.
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