We revisit supernova (SN) bounds on a hidden sector consisting of millicharged particles χ and a massless dark photon. Unless the self-coupling is fine-tuned to be small, rather than exiting the SN core as a gas, the particles form a relativistic fluid and subsequent dark QED fireball, streaming out against the drag due to the interaction with matter. Novel bounds due to excessive energy deposition in the mantle of low-energy supernovae can be obtained. The cooling bounds from SN 1987A are unexpectedly not affected in the free-streaming regime. The inclusion of χχ¯→standard model substantially modifies the constraints in the trapping regime, which can only be treated hydrodynamically. Our results can be adapted to generic sub-GeV self-interacting dark sectors. Published by the American Physical Society 2024

中文翻译：

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超新星中的自相互作用暗区可以表现为相对论性流体


我们重新审视了由毫带电粒子 χ 和无质量暗光子组成的隐藏扇区上的超新星 （SN） 边界。除非自耦合被微调到很小，而不是以气体的形式离开 SN 核心，否则粒子会形成相对论性流体，随后形成暗 QED 火球，由于与物质的相互作用而逆着阻力流出。可以获得由于低能超新星地幔中过度能量沉积而引起的新边界。SN 1987A 的冷却边界出乎意料地在免费流方案中不受影响。χχ ̄→standard 模型的加入大大改变了捕获状态中的约束，这只能通过流体动力学来处理。我们的结果可以适应通用的 sub-GeV 自相互作用暗扇区。 美国物理学会 2024 年出版