论文标题
银河系双光谱中的中微子质量签名
Neutrino Mass Signatures in the Galaxy Bispectrum
论文作者
论文摘要
在标准模型中，中微子是无质量的。但是，振荡实验表明它们的质量确实很小。当前，只有质量平方的差异，以及其总和上的上限。即将进行的对宇宙大规模结构（LSS）的调查，通过揭示中微子如何影响星系聚类，为探测中微子质量的途径提供了有希望的途径。大规模的中微子会影响扰动理论（PT）的结构形成框架内的模式耦合，并在PT内核中留下可检测的特征。在这项工作中，我们首次提出了大规模中微子引起的内核引起的核的明确修改，并研究了红移空间银河系双光谱中这些变化的程度。为此，我们使用理论协方差矩阵生成综合数据，并采用马尔可夫链蒙特卡洛（MCMC）来评估这些新签名项的影响。与Fisher的预测相反，这种方法使我们能够查看新术语是否诱导参数的中心值的变化。合成数据是为了反映两个不同的星系样品。第一个对应于斯隆数字天空调查（SDSS）BARYON振荡光谱调查（BOSS）数据释放12 cmass发光红色星系（LRG）样本，其特征在于$ v _ {\ rm eff} = 3 \; [{\ rm gpc}/hH]^3 $ and $ d $ d $ d $ d $ d $ d $ d $ d $ d $ d $ d $ d $ d $ d $ d $ d $ d $ d $ d $ d $ d $ 10^{ - 4} \; h/{\ rm mpc} $。第二个对应于黑暗能量光谱仪器（DESI）5年LRG样品，$ v _ {\ rm eff} = 25 \; [{\ rm gpc}/h]^3 $。我们的发现表明，忽略核中中微子质量效应可能会导致中心值转移，相当于根据DESI Y5样样品估计的星系偏见的大约1σ$。对于Boss CMAS的体积，虽然没有统计学意义，但不可忽略不可忽略。
In the Standard Model, neutrinos are massless. However, oscillation experiments demonstrate that they do have a small mass. Currently, only the differences of the masses squared are known, along with an upper bound on their sum. Upcoming surveys of the Universe's Large-Scale Structure (LSS) offer a promising avenue to probe neutrino mass by revealing how neutrinos influence galaxy clustering. Massive neutrinos affect mode coupling within the framework of Perturbation Theory (PT) for structure formation, leaving detectable signatures in the PT kernels. In this work, we present for the first time the explicit modifications to the kernels caused by massive neutrinos and investigate the extent of these changes in the redshift-space galaxy bispectrum. To this end, we generate synthetic data using a theoretical covariance matrix and employ Markov-Chain Monte Carlo (MCMC) to assess the impact of these new signature terms. This approach, in contrast to Fisher forecasting, allows us to see if the new terms induce shifts in the recovered central values of parameters. The synthetic data is produced to mirror two different galaxy samples. The first corresponds to the Sloan Digital Sky Survey (SDSS) Baryon Oscillation Spectroscopic Survey (BOSS) Data Release 12 CMASS Luminous Red Galaxy (LRG) sample, characterized by an effective volume of $V_{\rm eff} = 3 \;[{\rm Gpc}/h]^3$ and a number density of $\bar{n} = 3 \times 10^{-4} \;h/{\rm Mpc}$. The second corresponds to the Dark Energy Spectroscopic Instrument (DESI) Year 5 LRG sample with $V_{\rm eff} = 25 \;[{\rm Gpc}/h]^3$. Our findings indicate that neglecting neutrino mass effects in the kernels can result in a central value shift equivalent to approximately $1σ$ in the galaxy biases estimated from the DESI Y5-like sample. For the BOSS CMASS volume, the shift, though not statistically significant, is non-negligible.
