论文标题
快速无线电爆发来探测原始非高斯性
Probing primordial non-Gaussianity with Fast Radio Bursts
论文作者
论文摘要
快速无线电爆发（FRB）是当前未知来源的天体瞬变，到目前为止，在静脉外距离上已经检测到了几个事件。无线电信号的分散度度量（DM）是沿视线的集成电子密度的探针，因此允许在大规模结构内绘制电子分布。由于一小部分电子通过反馈从星系中排出，因此它们在大尺度上与光晕相关，因此角度DM相关性显示由原始非高斯性引起的规模依赖性偏差。尽管信号比星系聚类等其他探针弱，但FRB可能会探测大量的体积。我们表明，在研究FRB聚类信号需要很大的样本时，DM中的相关性是宇宙变化的限制，仅在大角度尺度上，只有$ \ sim 10^{3-4} $事件。 A tomographic analysis of the angular DM correlation function can constrain the local primordial bispectrum shape parameter $f_\mathrm{NL}$ to a precision down to ${f_\mathrm{NL}}\sim \mathcal{O}(1)$ depending on assumptions about the FRB redshift distribution and the astrophysical feedback on large scales.这使得FRB成为限制通货膨胀物理学的竞争探测。
Fast radio bursts (FRBs) are astrophysical transients of currently unknown origin, and so far several events have been detected at extragalactic distances. The dispersion measure (DM) of the radio signal is a probe of the integrated electron density along the line of sight and therefore allows to map the electron distribution within the large-scale structure. Since a fraction of electrons gets expelled from galaxies by feedback, they are anticorrelated with halos at large scales and hence the angular DM correlations show a scale-dependent bias caused by primordial non-Gaussianity. Although the signal is weaker than in other probes like galaxy clustering, FRBs can potentially probe considerably larger volumes. We show that while studying the FRB clustering signal requires very large samples, correlations in the DM are cosmic-variance limited on large angular scales with only $\sim 10^{3-4}$ events. A tomographic analysis of the angular DM correlation function can constrain the local primordial bispectrum shape parameter $f_\mathrm{NL}$ to a precision down to ${f_\mathrm{NL}}\sim \mathcal{O}(1)$ depending on assumptions about the FRB redshift distribution and the astrophysical feedback on large scales. This makes FRBs a competitive probe to constrain inflationary physics.
