论文标题
在Abelian-Higgs宇宙弦网上的多理性限制
Multi-messenger constraints on Abelian-Higgs cosmic string networks
论文作者
论文摘要
Abelian-Higgs（AH）模型中的Nielsen-Operen涡旋是量规场理论中宇宙字符串的最简单实现。大规模数值解决方案表明，从随机初始条件下产生的AH字符串网络的主要衰减通道是经典的场辐射。但是，他们还表明，在特殊的初始条件下，可以为抑制经典的场辐射而创建弦的环，并且表现得像Nambu-Goto（NG）字符串，具有主导的衰变通道进入重力辐射。这表明宇宙弦是高能颗粒和重力波的一般来源。在这里，我们采用了AH字符串网络的简单参数化，允许粒子和重力波的产生。通过参考针对NG状循环分布的特定模型，这为对该模型进行``多通信者''研究的基础设定了基础。我们发现，为了解释纳米格拉夫的检测可能的引力波背景，同时满足了来自宇宙微波背景的模拟和界限对Ng样环的限制，Planck单位$gμ$中的AH弦的张力以及Ng-like Loops loops Loops $ f _ $ f _ { ng}^{2.6} \ gtrsim 3.2 \ times 10^{ - 13} $ at 95 $ \％$ pusitive。另一方面，对于此类弦张力，弥漫性伽玛射线背景（DGRB）的约束表明，总网络能量的97美元以上应转换为暗物质（DM）或暗辐射。我们还考虑了歼灭横截面，质量和遗物丰度DM的质量限制。例如，对于500 GEV的DM质量，可以通过腐烂的AH字符串来解释观察到的遗物丰度，而Ah字符串也解释了纳米格拉夫信号。
Nielsen-Olesen vortices in the Abelian-Higgs (AH) model are the simplest realisations of cosmic strings in a gauge field theory. Large-scale numerical solutions show that the dominant decay channel of a network of AH strings produced from random initial conditions is classical field radiation. However, they also show that with special initial conditions, loops of string can be created for which classical field radiation is suppressed, and which behave like Nambu-Goto (NG) strings with a dominant decay channel into gravitational radiation. This indicates that cosmic strings are generically sources of both high-energy particles and gravitational waves. Here we adopt a simple parametrisation of the AH string network allowing for both particle and gravitational wave production. With a reference to a specific model for NG-like loop distribution, this sets the basis for a ``multi-messenger'' investigation of this model. We find that, in order to explain the NANOGrav detection of a possible gravitational wave background, while satisfying the constraint on NG-like loop production from simulations and bounds from the cosmic microwave background, the tension of the AH string in Planck units $Gμ$ and the fraction of the NG-like loops $f_{\rm NG}$ should satisfy $Gμf_{\rm NG}^{2.6} \gtrsim 3.2\times 10^{-13}$ at 95$\%$ confidence. On the other hand, for such string tensions, constraints from the diffuse gamma-ray background (DGRB) indicate that more than 97$\%$ of the total network energy should be converted to dark matter (DM) or dark radiation. We also consider joint constraints on the annihilation cross-section, the mass, and the relic abundance of DM produced by decays of strings. For example, for a DM mass of 500 GeV, the observed relic abundance can be explained by decaying AH strings that also account for the NANOGrav signal.
