透過暗物質及中子衰變異常的微中子模型

在原子核中，中子及質子會形成束縛態使得原子核穩定。而在原子核中，中子幾乎是穩定態。不過當中子在原子核外時（稱為自由中子），將會變得非常不穩定，並且透過理論計算自由中子的壽命大約為881.5±1.5 s。有了理論計算的結果，實驗量測也應該會有相似結果。但是事實卻不是如此。在多年前，美國團隊及法國團隊分別以 « Beam experiment »和 « Bottle experiment »量測中子的壽命。但是實驗結果明顯的有差異，起初物理學家覺得可能是某一組的實驗團隊有錯誤，才造成此誤差。近幾年，美國研究團隊進行了一項長期且嚴謹的實驗來探討之前的實驗中所有的誤差來源，最後反而是更確定了兩個實驗結果的差異性。至今為止中子的壽命依舊是個謎團。許多理論物理學家開始建立暗物質模型並且解釋中子衰變異常。而此研究報告也是建立一個暗物質模型來解釋中子衰變異常，此模型也可以透過暗物質及新的純量場計算出微中子質量。

關鍵字

中子衰變；暗物質；微中子

並列摘要

Inside the nucleus, there are protons and neutrons and they form the bound states. When neutron leave the nucleus, it will become an unstable particle which is called a free neutron. The free neutron lifetime is predicted to be 881.5±1.5 s by the Standard Model. For years the experimental measurement are basically consistent with the theoretical results. However, recently laboratories in USA (Beam experiment) and France (Bottle experiment) were shown that the neutron lifetime anomaly, namely a discrepancy of about 1% is found between the experimental measurements and the theoretical prediction. Regarding the neutron lifetime anomaly. We propose an new gauge U(1) symmetry portal to dark matter to resolve the neutron lifetime anomaly. The symmetry breaking pattern of this new gauge symmetry will also shed light on the neutrino mass generation through the quantum radioactive corrections.

並列關鍵字

neutron decay ； dark matter ； neutrino

參考文獻

[1] Ernest Ma. Veri able Radiative Seesaw Mechanism of Neutrino Mass and Dark Matter. Phys.Rev.D73:077301,2006.

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