Abstract
The temperature response functions of the Yohkoh/SXT are re-calculated based on the most recent elemental abundances and ionization balance available in the CHIANTI atomic database version 6.0.1. The new standard responses are calculated for three types of abundance; i.e., ‘coronal’, ‘hybrid’, and ‘photospheric’ abundances included in the CHIANTI database, and are available in SolarSoft since 2010. Comparison plots of the new and old response functions and filter ratios are available at the Yohkoh Legacy data Archive ( http://solar.physics.montana.edu/ylegacy ). The three new responses generally peak at higher temperatures (at ≈ 10 MK) than the former standard response (at ≈ 5.6 MK) based on Mewe’s spectral model. The new responses with coronal and hybrid abundances have higher peak counts by a factor of 3 and 2, respectively, than those with the photospheric abundances and the former response based on Mewe’s model. The correction of the filter ratios depends on the type of filter and the range of the ratios to be used. In the significant cases, the new filter ratio produces 20 to 30% higher temperatures than the previous calibration. The choice of elemental abundance has a strong influence on the derived temperatures and emission measures, and often produces a variation significantly larger than the statistical and systematic errors considered so far.
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Takeda, A. Characteristics of the Re-Calculated Yohkoh/SXT Temperature Response. Sol Phys 273, 295–306 (2011). https://doi.org/10.1007/s11207-011-9838-y
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DOI: https://doi.org/10.1007/s11207-011-9838-y