论文标题
新的太阳耀斑钙丰度毫无意外：SMM弯曲晶体光谱仪的结果
New Solar Flare Calcium Abundances with no Surprises: Results from the SMM Bent Crystal Spectrometer
论文作者
论文摘要
使用来自1940年至1989年之间的194个耀斑衰变（从B6.4到X13的分类），使用来自太阳最大任务弯曲晶体光谱仪（BCS）的X射线光谱估算耀斑等离子体中的钙丰度。Sylwester等人的先前工作。发现丰度因耀斑而异。使用更新的仪器参数在这里改进了该分析，并通过包括BCS观看的所有钙线，而不仅仅是共振线，从而大大增强了光子计数统计量。丰度的变化已通过平均丰度确认，$ a（{\ rm ca}）$（用$ a（{\ rm h}）= 12 $表达对数（{\ rm h}）= 12 $），等于194 flares的$ 6.77 \ pm 0.20 $（这项研究中的141个是新的）。该范围对应于比光球丰度大的1.7到7.2之间的因素，因此我们的结果与``FIP''（第一个电离电位）效应相一致，在这种效果中，CA（FIP = 6.11〜EV）（例如CA（FIP = 6.11〜EV））具有增强的冠状丰度，但与Solar Active Indications较大，但较大的范围是Solar Active Indication。 $ a（{\ rm ca}）$用于较小和较短的耀斑）。因此，对理论的小调整可能是必要的。
The calcium abundance in flare plasmas is estimated using X-ray spectra from the Solar Maximum Mission Bent Crystal Spectrometer (BCS) during the decays of 194 flares (GOES classifications from B6.4 to X13) occurring between 1980 and 1989. Previous work by Sylwester et al. found that the abundance varied from flare to flare. That analysis is improved on here using updated instrument parameters and by including all calcium lines viewed by the BCS instead of only the resonance line, so greatly enhancing the photon count statistics. The abundance variations are confirmed with the average abundance, $A({\rm Ca})$ (expressed logarithmically with $A({\rm H}) = 12$), equal to $6.77 \pm 0.20$ for 194 flares (141 of which are new in this study). This range corresponds to factors of between 1.7 and 7.2 larger than the photospheric abundance and so our results are in line with a ``FIP" (first ionization potential) effect whereby low-FIP elements like Ca (FIP = 6.11~eV) have enhanced coronal abundances. The Ca flare abundance is uncorrelated with solar activity indices, but weak correlations are suggested with GOES flare class and duration (larger $A({\rm Ca})$ for smaller and shorter flares). The ponderomotive force theory of Laming explaining the FIP effect gives a range of parameters within which our estimates of $A({\rm Ca})$ agree with the theory. However, this then gives rise to disagreements with previous estimates of the flare silicon and sulfur abundances, although those of argon and iron are in good agreement. Small adjustments of the theory may thus be necessary.
