论文标题
宇宙双折射测量对银河前景排放和仪器系统的鲁棒性
Robustness of cosmic birefringence measurement against Galactic foreground emission and instrumental systematics
论文作者
论文摘要
宇宙微波背景(CMB)的极化可用于搜索奇偶校验的过程,例如由Chern-Simons耦合到光伪cal的田地所预测的。这样的交互将$ e $模式旋转到观察到的CMB信号中的$ b $模式中,效果称为宇宙双折射。即使各向同性双折射可能与探测器的极化角度误解所产生的旋转相混淆,当将银河前景发射用作校准器时,这两种效应之间的脱位都会损坏。在这项工作中,我们使用Planck任务的高频工具的现实模拟来测试银河前景的发射和仪器系统对通过该技术获得的最近双折射测量的影响。我们的结果证明了该方法的鲁棒性,以防止极化角度和其他系统效应(例如强度对极化泄漏,梁泄漏或交叉极化效应)的误解。但是,我们的估计器对极化前景排放的$ EB $相关性很敏感。在这里,我们建议通过使用贝叶斯组件分离分析中产生的模板对前景信号进行建模,以纠正灰尘$ eb $引起的偏差,以将参数模型符合CMB数据。需要确认当前可用的尘埃模板(例如Commander Sky模型)的局限性,高精度的CMB数据以及超出修改后的黑体范式以外的灰尘的表征,以便将来获得对宇宙双折射的明确测量。
The polarization of the cosmic microwave background (CMB) can be used to search for parity-violating processes like that predicted by a Chern-Simons coupling to a light pseudoscalar field. Such an interaction rotates $E$ modes into $B$ modes in the observed CMB signal by an effect known as cosmic birefringence. Even though isotropic birefringence can be confused with the rotation produced by a miscalibration of the detectors' polarization angles the degeneracy between both effects is broken when Galactic foreground emission is used as a calibrator. In this work, we use realistic simulations of the High-Frequency Instrument of the Planck mission to test the impact that Galactic foreground emission and instrumental systematics have on the recent birefringence measurements obtained through this technique. Our results demonstrate the robustness of the methodology against the miscalibration of polarization angles and other systematic effects, like intensity-to-polarization leakage, beam leakage, or cross-polarization effects. However, our estimator is sensitive to the $EB$ correlation of polarized foreground emission. Here we propose to correct the bias induced by dust $EB$ by modeling the foreground signal with templates produced in Bayesian component-separation analyses that fit parametric models to CMB data. Acknowledging the limitations of currently available dust templates like that of the Commander sky model, high-precision CMB data and a characterization of dust beyond the modified blackbody paradigm are needed to obtain a definitive measurement of cosmic birefringence in the future.