论文标题
检测与Quijote和C-Bass异常微波发射的光谱变化
Detection of Spectral Variations of Anomalous Microwave Emission with QUIJOTE and C-BASS
论文作者
论文摘要
异常微波发射(AME)是频率范围内的银河弥漫发射的重要组成部分,$ 10 $ - $ 60 \,$ GHz,$ GHz,并在星际介质中介绍了次纳米大小的晶粒的特性。我们通过将Quijote实验的强度数据组合为$ 11 $,$ 13 $,$ 17 $,$ 17 $和$ GHz,$ GHz,$ 4.76 \ $ 4.76 \ $ 4.76 \ $ 4.76 \ $ 4.76 \ $ 4.76 \ $ 4.76 \ $ 4.76 \ $ 4.76 \ ghz和$ 4.76 \ $ 4.76 \ 1. $ 3000 \,$ GHz。 $ 1^{\ circ} $分辨率的物理参数的地图是通过Markov Chain Monte Carlo(MCMC)拟合的光谱能量分布(SEDS)生成的,从而近似具有对数正态分布的AME组件。在沿光解离区域(PDRS)周围的整个环上的度尺度上检测到AME超过$ 20 \,σ$,其中三个主要明亮区域包含乌云。在AME峰值频率中观察到径向减小,从$ \ of \ \ of 35 \,$ GHz在自由区附近的$ hz到$ \ y \ of of $ \ of21 \,$ ghz,$ ghz在环的外部区域,这是对单个区域的AME光谱变化的首次检测。 AME峰频率,发射度量和尘埃温度之间的强相关性是AME峰频率在局部辐射场上的依赖性的指示。通过光学深度归一化的AME振幅也与辐射场密切相关,从而使整体情况与旋转的灰尘一致,其中局部辐射场起着关键作用。
Anomalous Microwave Emission (AME) is a significant component of Galactic diffuse emission in the frequency range $10$-$60\,$GHz and a new window into the properties of sub-nanometre-sized grains in the interstellar medium. We investigate the morphology of AME in the $\approx10^{\circ}$ diameter $λ$ Orionis ring by combining intensity data from the QUIJOTE experiment at $11$, $13$, $17$ and $19\,$GHz and the C-Band All Sky Survey (C-BASS) at $4.76\,$GHz, together with 19 ancillary datasets between $1.42$ and $3000\,$GHz. Maps of physical parameters at $1^{\circ}$ resolution are produced through Markov Chain Monte Carlo (MCMC) fits of spectral energy distributions (SEDs), approximating the AME component with a log-normal distribution. AME is detected in excess of $20\,σ$ at degree-scales around the entirety of the ring along photodissociation regions (PDRs), with three primary bright regions containing dark clouds. A radial decrease is observed in the AME peak frequency from $\approx35\,$GHz near the free-free region to $\approx21\,$GHz in the outer regions of the ring, which is the first detection of AME spectral variations across a single region. A strong correlation between AME peak frequency, emission measure and dust temperature is an indication for the dependence of the AME peak frequency on the local radiation field. The AME amplitude normalised by the optical depth is also strongly correlated with the radiation field, giving an overall picture consistent with spinning dust where the local radiation field plays a key role.