Simultaneous spectropolarimetric observations in the H and Ca II 8662 lines of an active region

We present spectropolarimetric observations of an active region recorded simultaneously in the H Ca II 8662 lines. The sunspot exhibits multiple structures, including a lightbridge and a region where Ca II 8662 line core is in emission. Correspondingly, the H line core image displays brightening in the emission region, with the spectral profiles showing elevated line cores. The stratification of the line-of-sight magnetic field is inferred through non-LTE multiline inversions of the Ca II 8662 line and the weak field approximation over the H line. The field strength inferred from the H line core is consistently smaller than that inferred from inversions at ₅₀₀ = -4. 5. However, the study finds no correlation between the WFA over the core of the H line and that inferred from inversions at ₅₀₀ = -4. 5. In regions exhibiting emission features, the morphology of the magnetic field at ₅₀₀ = -4. 5 resembles that at ₅₀₀ = -1, with slightly higher or comparable field strengths. The magnetic field morphology inferred from the core of the H line is also similar to that inferred from the full spectral range of the H line in the emission region. The field strength inferred in the lightbridge at ₅₀₀ = -1 is smaller than the surrounding umbral regions and comparable at ₅₀₀ = -4. 5. Similarly, the field strength inferred in the lightbridge from the WFA over the H line appears lower compared to the surrounding umbral regions.