Coherent forward neutron propagation in gas is discussed as a new approach to search for neutron-antineutron oscillations ($ n-\bar{n}$), which violate both $B$ and $B-L$ conservation. We show that one can increase the probability of neutron - antineutron transitions to essentially the free neutron oscillation rate in the presence of a nonzero external magnetic field by tuning the density of an appropriate mixture of gases so that the neutron optical potential of the gas cancels that from an external magnetic field.

中文翻译：

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一种利用气体中相干中子传播寻找自由中子-反中子振荡的新方法

气体中的相干正向中子传播被讨论为一种寻找中子-反中子振荡 ($n-\bar{n}$) 的新方法，它违反了 $B$ 和 $BL$ 守恒。我们表明，在存在非零外部磁场的情况下，可以通过调整适当的气体混合物的密度来增加中子 - 反中子跃迁到基本上自由中子振荡率的概率，从而使气体的中子光势抵消来自外部磁场。