论文标题
光谱分辨率对MG II H＆K线的简单磁场诊断的影响
Effects of spectral resolution on simple magnetic field diagnostics of the Mg II h & k lines
论文作者
论文摘要
我们研究有限光谱分辨率对通过Mg II H＆K系的核心从弱场近似（WFA）检索的磁场值的影响。从均匀磁化的FAL-C大气中产生的合成光谱从磁场的$ b _ {\ rm los} $中检索的检索是准确的线芯通过光谱涂抹，降低了WFA的准确性并导致推理偏差，这更明显地分辨率较差。当应用于来自黑子模拟的各种光谱集时，当将其与线核中光学深度的高度上的模型值进行比较时，我们发现检索到的$ b _ {\ rm los} $的准确性良好。将精度保留到B〜1500 G的田间强度。还评估了磁场横向分量的WFA。降低的光谱分辨率降低了推论的准确性，因为光谱混合导致线有效地探测了大气的更深层。
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 & k lines. The retrieval of the line-of-sight (LOS) component of the magnetic field, $B_{\rm LOS}$, from synthetic spectra generated in a uniformly magnetized FAL-C atmosphere are accurate when restricted to the inner lobes of Stokes V. As we degrade the spectral resolution, partial redistribution (PRD) effects, that 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 the poorer the resolution. When applied to a diverse set of spectra emerging from a sunspot simulation, we find a good accuracy in the retrieved $B_{\rm LOS}$ 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.
