Title: QUIJOTE scientific results -- IV. A northern sky survey in intensity and polarization at 10-20GHz with the Multi-Frequency Instrument Show Chinese title

Title: QUIJOTE科学结果——IV。 在10-20GHz频段对北天区进行强度和偏振的巡天观测，使用多频段仪器

Abstract: We present QUIJOTE intensity and polarization maps in four frequency bands centred around 11, 13, 17 and 19GHz, and covering approximately 29000 deg$^2$, including most of the Northern sky region. These maps result from 9000 h of observations taken between May 2013 and June 2018 with the first QUIJOTE instrument (MFI), and have angular resolutions of around $1^\circ$, and sensitivities in polarization within the range 35-40 $\mu$K per 1-degree beam, being a factor $\sim 2$-$4$ worse in intensity. We discuss the data processing pipeline employed, and the basic characteristics of the maps in terms of real space statistics and angular power spectra. A number of validation tests have been applied to characterise the accuracy of the calibration and the residual level of systematic effects, finding a conservative overall calibration uncertainty of 5%. We also discuss flux densities for four bright celestial sources (Tau A, Cas A, Cyg A and 3C274) which are often used as calibrators at microwave frequencies. The polarization signal in our maps is dominated by synchrotron emission. The distribution of spectral index values between the 11GHz and WMAP 23GHz map peaks at $\beta=-3.09$ with a standard deviation of 0.14. The measured BB/EE ratio at scales of $\ell=80$ is $0.26\pm 0.07$ for a Galactic cut $|b|>10^\circ$. We find a positive TE correlation for 11GHz at large angular scales ($\ell \lesssim 50$), while the EB and TB signals are consistent with zero in the multipole range $30 \lesssim \ell \lesssim 150$. The maps discussed in this paper are publicly available. Show Chinese abstract

Abstract: 我们展示了围绕11、13、17和19GHz四个频率带的QUIJOTE强度和偏振图，覆盖大约29000度$^2$，包括大部分北天区域。 这些图像是在2013年5月至2018年6月期间使用第一个QUIJOTE仪器（MFI）进行的9000小时观测结果，具有大约$1^\circ$的角分辨率，偏振灵敏度范围为每1度光束35-40 $\mu$K，强度方面则要差$\sim 2$-$4$倍。 我们讨论了所采用的数据处理流程，以及图在实空间统计和角功率谱方面的基本特性。 已应用多项验证测试以表征校准精度和系统效应的残余水平，发现校准的总体不确定性保守地为5%。 我们还讨论了四个明亮天体源（Tau A、Cas A、Cyg A和3C274）的流量密度，这些源常用于微波频率的校准。 我们图中的偏振信号主要由同步辐射发射主导。 在11GHz和WMAP 23GHz图之间的光谱指数分布峰值为$\beta=-3.09$，标准偏差为0.14。 测量在$\ell=80$尺度下的 BB/EE 比率是$0.26\pm 0.07$对于银河系切割$|b|>10^\circ$。 我们在 11GHz 处发现大角度尺度 ($\ell \lesssim 50$) 下的 TE 相关性为正，而 EB 和 TB 信号在多极范围$30 \lesssim \ell \lesssim 150$内与零一致。 本文讨论的地图是公开可用的。