论文标题
使用低频成像达到小尺度：应用到黑暗时代
Reaching small scales with low frequency imaging: applications to the Dark Ages
论文作者
论文摘要
早期宇宙中密度扰动的初始条件决定了我们今天看到的星系的大规模结构和分布，这是在通货膨胀期间设定的。原始非高斯性的测量对于区分不同的通货膨胀模型至关重要。来自CMB的物质功率谱的当前测量仅在缩放下限制了$ k \ sim 0.1 $ mpc $^{ - 1} $。达到较小的角度尺度（$ k $的较高值）可以对非高斯性提供新的约束。一种有力的方法是测量$ \ textrm {h} \ textrm {i} $ Matter Power Spectrum in $ z \ gtrsim30 $。在本文中，我们调查了低频阵列（Lofar）可以达到$ K $的值，该值可以实现$ \ lyssim $ 1 $''''$ $ \，$ $ \ sim $ \ sim $ 50 MHz。将其与一种将频谱平滑的前景隔离到$ k _ {\ Parallel} $ - $ k _ {\ perp} $ space中的楔形的技术，我们演示了我们可以在观测约束中可行的$ k $的值。我们发现Lofar是$ \ sim $ 5级数量级，距离所需的敏感性距离10年了。
The initial conditions for the density perturbations in the early Universe, which dictate the large scale structure and distribution of galaxies we see today, are set during inflation. Measurements of primordial non-Gaussianity are crucial for distinguishing between different inflationary models. Current measurements of the matter power spectrum from the CMB only constrain this on scales up to $k\sim 0.1$ Mpc$^{-1}$. Reaching smaller angular scales (higher values of $k$) can provide new constraints on non-Gaussianity. A powerful way to do this is by measuring the $\textrm{H}\textrm{I}$ matter power spectrum at $z\gtrsim30$. In this paper, we investigate what values of $k$ can be reached for the LOw Frequency ARray (LOFAR), which can achieve $\lesssim$1$''$ $\,$resolution at $\sim$50 MHz. Combining this with a technique to isolate the spectrally smooth foregrounds to a wedge in $k_{\parallel}$ - $k_{\perp}$ space, we demonstrate what values of $k$ we can feasibly reach within observational constraints. We find that LOFAR is $\sim$5 orders of magnitude away from the desired sensitivity, for 10 years of integration time.
