标题： 揭示具有伪NGB暗物质及其引力波信号的惰性三重荒漠区 显示英文标题

标题： Unveiling the inert Triplet desert region with a pNGB Dark Matter and its Gravitational Wave signatures

摘要： 在这项工作中，我们将常规无超电荷惰性三重态模型（ITM）的标量部分扩展，以包括第二种暗物质（DM）候选者，该候选者似乎是一种伪Nambu-Goldstone玻色子（pNGB）。 具有扩展标量部分的传统ITM提供了DM候选者以及不同实验中的新颖信号，例如对撞机、引力波探测器等。 然而，迄今为止未被发现的实验检测已经对ITM参数空间施加了严格的限制。 此外，与现有的或即将来临的对撞机灵敏度范围一致的轻于 $1.9$ TeV 的三重态质量，由于强烈的 $SU(2)_L$ 规范湮灭，已经从DM可观测的角度排除了，因为它们导致剩余密度不足。 通过一个复杂的 $SU(2)_L$ 标量单态和 $U(1)$ 对称性的软破缺，引入一种pNGB DM有助于复兴三重态DM的亚TeV区域。 这种复兴依赖于两种DM物种之间的有效转换。 利用这种相互转化，以三重态DM作为两者中较轻的一种，我们表明可以将其贡献推至 $50\% - 60\%$ 的总剩余密度。 这比只有一个DM候选者的传统ITM有了显著改进，在传统ITM中，相同情况最多只能达到 $10\% - 20\%$。 此外，相关的二分DM框架还提供了在各种组成场方向上发生一级相变的可能性。 其中，沿着实数 $SU(2)_L$ 单态方向的一级相变可能是强的，随后在即将到来的空间引力波探测器如LISA、BBO、DECIGO等中产生可探测的引力波信号，并且在各种DM和对撞机探索中产生独特且互补的信号。 显示英文摘要

摘要： In this work, we extend the scalar sector of the conventional hyperchargeless inert triplet model (ITM) to include a second dark matter (DM) candidate, which appears to be a pseudo-Nambu-Goldstone boson (pNGB). The usual ITM with an extended scalar sector offers a DM candidate along with novel signatures at different experiments, e.g., colliders, gravitational wave detectors, etc. Nevertheless, hitherto unseen experimental detections have placed stringent constraints on the ITM parameter space. Moreover, triplet masses lighter than $1.9$ TeV, consistent with the existing or upcoming collider sensitivity reach, are already excluded from the DM observable, as they yield an underabundant relic density due to a strong $SU(2)_L$ gauge annihilation. Inclusion of a pNGB DM, via a complex $SU(2)_L$ scalar singlet and through the soft-breaking of a $U(1)$ symmetry, helps to revive the sub-TeV regime of the triplet DM. This resurgence relies on a proficient conversion between the two DM species. Using this inter-conversion, with the triplet DM as the lighter one between the two, we show that it is possible to push the triplet DM contribution to $50\% - 60\%$ of the total relic density. This offers a significant improvement over the traditional ITM with a single DM candidate, where the same can at most reach $10\% - 20\%$. Besides, the concerned bipartite DM framework also offers the possibility of a first-order phase transition along various constituent field directions. Among these, the one along the real $SU(2)_L$ singlet direction can be a strong one which subsequently yields detectable gravitational wave signals at the upcoming space-based gravitational wave detectors such as LISA, BBO, DECIGO, etc., alongside distinctive and complementary signatures at the various DM and collider quests.