Goldman Itzhak, Mohapatra Rabindra N, Nussinov Shmuel, Zhang Yongchao
Afeka College and Tel Aviv University, 6195001 Tel Aviv, Israel.
Maryland Center for Fundamental Physics and Department of Physics, University of Maryland, College Park, Maryland 20742, USA.
Phys Rev Lett. 2022 Aug 5;129(6):061103. doi: 10.1103/PhysRevLett.129.061103.
It was pointed out in a recent paper that the observed cooling rate of old, cold neutron stars (NS) can provide an upper limit on the transition rate of neutron to mirror neutron (n-n^{'}). This limit is so stringent that it would preclude any discovery of n→n^{'} oscillation in the current round of terrestrial searches for the process. Motivated by this crucially important conclusion, we critically analyze this suggestion and note an interesting new effect present in nearly exact mirror models for n→n^{'} oscillation, which significantly affects this bound. The new element is the β decay n^{'}→p^{'}+e^{'}+ν[over ¯]_{e}^{'}, which creates a cloud of mirror particles n^{'}, p^{'}, e^{'}, and D^{'} inside the NS core. The e^{'} can "rob" the energy generated by the n→n^{'} transition via e-e^{'} scattering enabled by the presence of a (minute) millicharge in mirror particles. This energy is emitted as unobserved mirror photons via fast mirror bremsstrahlung leading to a relaxation of this upper limit.
最近一篇论文指出，观测到的老年冷中子星（NS）的冷却速率可以为中子到镜像中子（n - n′）的转变速率提供一个上限。这个上限非常严格，以至于在当前一轮地面寻找该过程的实验中，它会排除任何n→n′振荡的发现。受这个极其重要的结论启发，我们批判性地分析了这个提议，并注意到在n→n′振荡的近乎精确的镜像模型中存在一个有趣的新效应，它会显著影响这个界限。新的因素是β衰变n′→p′ + e′ + ν̅e′，它在NS核心内部产生了一团镜像粒子n′、p′、e′和D′。e′可以通过镜像粒子中存在的（微小的）毫电荷所促成的e - e′散射，“掠夺”由n→n′转变产生的能量。这些能量通过快速镜像轫致辐射以未被观测到的镜像光子形式发射出去，从而导致这个上限的放宽。
