标题： 利用太极探测宇宙相变：灵敏度分析与参数估计 显示英文标题

标题： Detecting Cosmological Phase Transitions with Taiji: Sensitivity Analysis and Parameter Estimation

摘要： 我们研究了太极空间引力波探测器对早期宇宙一阶相变产生的随机引力波背景的探测能力。通过一个综合模拟框架，该框架包含了现实的仪器噪声、银河系双白矮星混淆噪声以及河外紧凑双星背景，我们系统地分析了太极探测器在不同信号参数范围内的灵敏度。我们的贝叶斯分析表明，太极探测器能够在大部分频率范围内稳健地探测并表征能量密度超过$Ω_{\text{PT}} \gtrsim 1.4 \times 10^{-11}$的相变信号，在$10^{-3}$到$10^{-2}$赫兹频段内尤其具有较强的灵敏度。对于幅度高于$Ω_{\text{PT}} \gtrsim 1.1 \times 10^{-10}$的信号，太极可以以优于$10\%$的相对精度确定峰值频率。这些探测能力将使太极能够探测超出标准模型的各种电弱尺度相变情景，可能揭示与重子生成和暗物质产生相关的新的物理现象。我们使用贝叶斯因子和偏差信息准则量化了探测置信度，发现一致的结果验证了我们的统计方法。 显示英文摘要

摘要： We investigate the capability of the Taiji space-based gravitational wave observatory to detect stochastic gravitational wave backgrounds produced by first-order phase transitions in the early universe. Using a comprehensive simulation framework that incorporates realistic instrumental noise, galactic double white dwarf confusion noise, and extragalactic compact binary backgrounds, we systematically analyze Taiji's sensitivity across a range of signal parameters. Our Bayesian analysis demonstrates that Taiji can robustly detect and characterize phase transition signals with energy densities exceeding $Ω_{\text{PT}} \gtrsim 1.4 \times 10^{-11}$ across most of its frequency band, with particularly strong sensitivity around $10^{-3}$ to $10^{-2}$ Hz. For signals with amplitudes above $Ω_{\text{PT}} \gtrsim 1.1 \times 10^{-10}$, Taiji can determine the peak frequency with relative precision better than $10\%$. These detection capabilities would enable Taiji to probe electroweak-scale phase transitions in various beyond-Standard-Model scenarios, potentially revealing new physics connected to baryogenesis and dark matter production. We quantify detection confidence using both Bayes factors and the Deviance Information Criterion, finding consistent results that validate our statistical methodology.