论文标题
lyman- $α$极化强度映射
Lyman-$α$ Polarization Intensity Mapping
论文作者
论文摘要
我们提出了一种形式主义，该形式主义结合了氢αα（ly $α$）极化，这是由于星系光环中的辐射散射到强度映射方法中。 Using the halo model, and emission profiles based on simulations and observations, we calculate auto and cross power spectra at redshifts $3\leq z \leq13$ for the Ly$α$ total intensity, $I$, polarized intensity, $P$, degree of polarization, $Π=P/I$, and two new quantities, the astrophysical $E$ and $B$ modes of Ly$α$ polarization. $π$功率谱的单次术语显示出一个营业额，这表明了极化信号的平均程度，因此表明了散射介质的范围。此功能的位置取决于红移，以及在我们的形式主义中的特定发射曲线和程度。因此，将各种$α$极化量和红移的比较可以打破竞争效果之间的脱整流，并且可以揭示发射曲线的真实形状，从而揭示了光环中凉气的物理特性。此外，可以将LY $α$ $ e $和$ b $模式的测量值用作银河发展的探针，因为它们与发射中的平均各向异性程度以及跨红移的光晕气分布有关。在$ z \ sim 3-5 $中检测极化信号需要改善当前基于地面实验的敏感性$ \ sim 10 $，而$ \ sim 100 $用于针对Redshifts $ z \ sim 9-10 $的空间仪器的$ \ sim 100 $，根据特定的redShift和实验的确切值。极化中的闯入者污染预计将很小，因为室内流动器也需要极化。总体而言，Ly $α$极化可以增加在星系及其周围环境上可检索的物理信息的量，仅在总发射的情况下，大部分无法实现。 （简略）
We present a formalism that incorporates hydrogen Lyman-alpha (Ly$α$) polarization arising from the scattering of radiation in galaxy halos into the intensity mapping approach. Using the halo model, and emission profiles based on simulations and observations, we calculate auto and cross power spectra at redshifts $3\leq z \leq13$ for the Ly$α$ total intensity, $I$, polarized intensity, $P$, degree of polarization, $Π=P/I$, and two new quantities, the astrophysical $E$ and $B$ modes of Ly$α$ polarization. The one-halo terms of the $Π$ power spectra show a turnover that signals the average extent of the polarization signal, and thus the extent of the scattering medium. The position of this feature depends on redshift, and on the specific emission profile shape and extent, in our formalism. Therefore, the comparison of various Ly$α$ polarization quantities and redshifts can break degeneracies between competing effects, and it can reveal the true shape of the emission profiles, and thus, the physical properties of the cool gas in halos. Furthermore, measurements of Ly$α$ $E$ and $B$ modes may be used as probes of galaxy evolution, because they are related to the average degree of anisotropy in the emission and in the halo gas distribution across redshifts. The detection of the polarization signal at $z \sim 3-5$ requires improvements in the sensitivity of current ground-based experiments by a factor of $\sim 10$, and of $\sim 100$ for space-based instruments targeting the redshifts $z\sim 9-10$, the exact values depending on the specific redshift and experiment. Interloper contamination in polarization is expected to be small, because the interlopers need to also be polarized. Overall, Ly$α$ polarization boosts the amount of physical information retrievable on galaxies and their surroundings, most of it not achievable with total emission alone. (abridged)
