论文标题
旋转 - $ 1/2 $沉重的中膜中的隐形粒子
Spin-$1/2$ invisible particles in heavy meson decays
论文作者
论文摘要
研究了$ b $和$ b_c $介子的最终状态涉及旋转$ 1/2 $颗粒的$ b $和$ b_c $介子的中性衰减过程。通过考虑标准模型的背景，其中$ν\barν$贡献了分支分数的缺失能量和实验上限，我们得到了夸克 - 易药的耦合常数的约束和假定的无形粒子$χ\ bar的限制。然后，使用耦合常数的约束来研究$ b_c $梅森的类似过程。在$M_χ$的某个特定区域，Br的上限（$ b_c \ to d _ {（s）}χ\barχ$）的订单为$ 10^{ - 6} $，而对于Br（$ b_c \ to d^\ to d^\ ast _ ast _ {（s）{（s）}（s）}χ\barχ$）还讨论了将$χ$区分为Majorana或Dirac Fermion的可能性。
The flavor-changing neutral current decay processes of the $B$ and $B_c$ mesons with the final states involving spin-$1/2$ particles are investigated. By considering the background of the Standard Model where $ν\barν$ contributes the missing energy and the experimental upper bounds for the branching fractions, we get the constraints of the coupling constants of the quark-antiquark and the assumed invisible particles $χ\barχ$. The constraints of the coupling constants are then used to study the similar processes of the $B_c$ meson. At some specific region of $m_χ$, the upper limit of BR($B_c\to D_{(s)}χ\barχ$) is of the order of $10^{-6}$, while for BR($B_c\to D^\ast_{(s)}χ\barχ$), it is $10^{-5}$. The possibility of distinguishing $χ$ to be a Majorana or Dirac fermion by the differential branching fractions is also discussed.
