论文标题
在迷人的哈德子的衰减中寻求无质量的黑暗光子
Seeking massless dark photons in the decays of charmed hadrons
论文作者
论文摘要
无质量的深色光子只能通过高维操作员影响标准模型颗粒，因此可以避免最近对其大规模对应物进行搜索，该搜索是基于以下假设：后者由于计量仪的运动混合而与已知的费米子具有可重新分布的相互作用。在这项研究中，我们很可能会使无质量的黑暗光子与$ u $和$ u $和$ c $ quarks具有不可忽略的偶极式偶极式耦合，从而使魅力的Hadron的衰减变成了一个较轻的Hadron，加上黑暗光子带来的缺失的能量。我们建议调查这种衰变，尤其是父母是迷人的伪calloscalar-mesons $ d^+$，$ d^0 $，以及$ d_s^+$和singly Charmed Baryons $λ_C^+$，$ Cement_c^+$，$ CC^+$，以及$ξ_c^0 $。采用满足相关约束的简化新物理模型，我们发现这些过程的分支分数可能会大至几次$ 10^{-5} $。这表明其中一个或多个可能在不久的将来落在正在进行的Belle II和Besiii实验的范围内。由于相同的基础运算符负责所有这些过渡，因此检测其中一个自动意味着对其他过渡的特定预测，从而可以对无质量漆的情况进行其他实验检查。
A massless dark photon could affect standard-model particles only via higher-dimensional operators and would therefore have eluded recent searches for its massive counterpart, which were based on the assumption that the latter had renormalizable interactions with known fermions due to gauge kinetic mixing. In this study we entertain the possibility that the massless dark photon has nonnegligible flavor-changing dipole-type couplings with the $u$ and $c$ quarks, giving rise to the decays of charmed hadrons into a lighter hadron plus missing energy carried away by the dark photon. We propose to investigate decays of this kind, especially those in which the parents are the charmed pseudoscalar-mesons $D^+$, $D^0$, and $D_s^+$ and singly charmed baryons $Λ_c^+$, $Ξ_c^+$, and $Ξ_c^0$. Employing a simplified new-physics model satisfying the relevant constraints, we find that the branching fractions of these processes could be as large as several times $10^{-5}$. This suggests that one or more of them might in the near future fall within reach of the ongoing Belle II and BESIII experiments. Since the same underlying operators are responsible for all of these transitions, detecting one of them automatically implies particular predictions for the others, allowing for additional experimental checks on the massless-dark-photon scenario.
