Effects of Spectral Resolution on Simple Magnetic Field Diagnostics of the Mg ii H and K Lines
Effects of Spectral Resolution on Simple Magnetic Field Diagnostics of the Mg ii H and K Lines
复制标题
光谱分辨率对 Mg ii H 线和 K 线简单磁场诊断的影响
DOI：
10.3847/1538-4357/ac886f
复制
发表时间：
2022
期刊：
影响因子：
--
通讯作者：
T. del Pino Alemán
中科院分区：
文献类型：
--
作者：
R. Centeno;M. Rempel;R. Casini;T. del Pino Alemán
我们研究了有限的光谱分辨率上的磁场值检索通过弱场近似（WFA）从核心的Mg II H和K线的影响。当限制在斯托克斯V的内瓣时，从均匀磁化的B-C大气中产生的合成光谱中反演磁场的视线分量B LOS是准确的。当我们降低光谱分辨率时，部分再分布效应，其更显著地影响斯托克斯V的外瓣，通过光谱涂抹被带入线芯，降低了WFA的准确性并导致推理偏差，这随着分辨率变差而更加明显。当应用到一组不同的光谱出现从太阳黑子模拟，我们发现检索B LOS的准确性很好，当比较它的模型值的高度，其中的光学深度线核心是统一的。精度可保持到B ~ 1500 G的场强。有限的光谱分辨率的结果在一个小的偏向较弱的检索领域。还评估了磁场横向分量的WFA。降低光谱分辨率会降低推断的准确性，因为光谱混合会导致谱线有效地探测大气的更深层。
We study the effects of finite spectral resolution on the magnetic field values retrieved through the weak-field approximation (WFA) from the cores of the Mg ii h and k lines. The retrieval of the line-of-sight component of the magnetic field, B LOS, from synthetic spectra generated in a uniformly magnetized FAL-C atmosphere is accurate when restricted to the inner lobes of Stokes V. As we degrade the spectral resolution, partial redistribution effects, which more prominently affect the outer lobes of Stokes V, are brought into the line core through spectral smearing, degrading the accuracy of the WFA and resulting in an inference bias, which is more pronounced as the resolution becomes poorer. When applied to a diverse set of spectra emerging from a sunspot simulation, we find good accuracy in the retrieved B LOS when comparing it to the model value at the height where the optical depth in the line core is unity. The accuracy is preserved up to field strengths of B ∼ 1500 G. Limited spectral resolution results in a small bias toward weaker retrieved fields. The WFA for the transverse component of the magnetic field is also evaluated. Reduced spectral resolution degrades the accuracy of the inferences, because spectral mixing results in the line effectively probing deeper layers of the atmosphere.
影响因子：
2.8
作者：
Kosugi, T.;Matsuzaki, K.;Golub, L.
通讯作者：
Golub, L.