Numerous studies have analysed inferred power-law distributions between frequency and energy of impulsive events in the outer solar atmosphere in an attempt to understand the predominant energy supply mechanism in the corona. Here, we apply a burst detection algorithm to high-resolution imaging data obtained by the Interface Region Imaging Spectrograph to further investigate the derived power-law index, $\gamma$, of bright impulsive events in the transition region. Applying the algorithm with a constant minimum event lifetime (of either $60$ s or $110$ s) indicated that the target under investigation, such as Plage and Sunspot, has an influence on the observed power-law index. For regions dominated by sunspots, we always find $\gamma 2$ in the energy range [$\sim10^{23}$, $\sim10^{26}$] erg. Applying the algorithm with a minimum event lifetime of three timesteps indicated that cadence was another important factor, with the highest cadence datasets returning $\gamma >2$ values. The estimated total radiative power obtained for the observed energy distributions is typically 10-25 % of what would be required to sustain the corona indicating that impulsive events in this energy range are not sufficient to solve coronal heating. If we were to extend the power-law distribution down to an energy of $10^{21}$ erg, and assume parity between radiative energy release and the deposition of thermal energy, then such bursts could provide 25-50 % of the required energy to account for the coronal heating problem.

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活动太阳上小尺度脉冲事件的幂律能量分布：来自 IRIS 的结果

许多研究分析了外太阳大气中脉冲事件的频率和能量之间推断的幂律分布，以试图了解日冕中的主要能量供应机制。在这里，我们将突发检测算法应用于界面区域成像光谱仪获得的高分辨率成像数据，以进一步研究过渡区域中明亮脉冲事件的导出幂律指数 $\gamma$。应用具有恒定最小事件生存期（$60$s 或 $110$s）的算法表明被调查的目标，例如 Plage 和 Sunspot，对观察到的幂律指数有影响。对于以太阳黑子为主的区域，我们总是在能量范围 [$\sim10^{23}$, $\sim10^{26}$] erg 中找到 $\gamma 2$。应用具有三个时间步长的最小事件生存期的算法表明节奏是另一个重要因素，最高节奏数据集返回 $\gamma >2$ 值。为观察到的能量分布获得的估计总辐射功率通常是维持日冕所需能量的 10-25%，表明该能量范围内的脉冲事件不足以解决日冕加热问题。如果我们将幂律分布扩展到 $10^{21}$ erg 的能量，并假设辐射能释放和热能沉积之间是相等的，那么这种爆发可以提供所需能量的 25-50%以解决日冕加热问题。为观察到的能量分布获得的估计总辐射功率通常是维持日冕所需能量的 10-25%，表明该能量范围内的脉冲事件不足以解决日冕加热问题。如果我们将幂律分布扩展到 $10^{21}$ erg 的能量，并假设辐射能释放和热能沉积之间是相等的，那么这种爆发可以提供所需能量的 25-50%以解决日冕加热问题。为观察到的能量分布获得的估计总辐射功率通常是维持日冕所需能量的 10-25%，表明该能量范围内的脉冲事件不足以解决日冕加热问题。如果我们将幂律分布扩展到 $10^{21}$ erg 的能量，并假设辐射能释放和热能沉积之间是相等的，那么这种爆发可以提供所需能量的 25-50%以解决日冕加热问题。