Can TRACE Extreme-Ultraviolet Observations of Cooling Coronal Loops Be Used to Determine the Heating Parameters?
Can TRACE Extreme-Ultraviolet Observations of Cooling Coronal Loops Be Used to Determine the Heating Parameters?
复制标题
TRACE 冷却日冕环的极紫外观测可以用来确定加热参数吗？
DOI：
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发表时间：
2004
期刊：
影响因子：
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通讯作者：
H. Warren
中科院分区：
文献类型：
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作者：
A. Winebarger;H. Warren
最近对TRACE观测到的相对较冷（101 MK）的活动区环的分析表明，这些环已经被脉冲加热，并通过TRACE带通冷却。在这封信中，我们探讨了冷却回路的演变，以确定TRACE EUV观测是否可以用于确定能量释放的幅度，持续时间和位置。我们发现，在一个脉冲加热冷却回路的顶点密度和温度的演变只取决于总能量沉积（而不是大小，持续时间，或能量沉积的位置）后，循环冷却过去的“平衡点”，其中的传导和辐射冷却时间是可比的。因此，必须在环的演化早期进行观测，以确定加热参数。典型的TRACE观测冷却回路不提供足够的信息来区分不同的加热方案。
Recent analysis of relatively cool (∼1 MK) active region loops observed with TRACE has suggested that these loops have been heated impulsively and are cooling through the TRACE bandpasses. In this Letter we explore the evolution of cooling loops to determine if the TRACE EUV observations can be used to determine the magnitude, duration, and location of the energy release. We find that the evolution of the apex density and temperature in an impulsively heated cooling loop depends only on the total energy deposited (not the magnitude, duration, or location of the energy deposition) after the loop cools past an "equilibrium point," where the conductive and radiative cooling times are comparable. Hence, observations must be made early in the evolution of a loop to determine the heating parameters. Typical TRACE observations of cooling loops do not provide adequate information to discriminate between different heating scenarios.