We report on results of systematic analyses of the entire three X-ray data sets of Jupiter taken by Suzaku in 2006, 2012, and 2014. Jovian diffuse hard X-ray emission was discovered by Suzaku in 2006 when the solar activity went toward its minimum. The diffuse emission was spatially consistent with the Jovian inner magnetosphere and was spectrally fitted with a flat power-law function suggesting non-thermal emission. Thus, a scenario in which ultra-relativistic (tens of MeV) electrons in the Jovian inner magnetosphere inverse-Comptonize solar visible photons into X-ray bands has been hypothetically proposed. We focused on the dependence of the Jovian diffuse hard X-ray emission on the solar activity to verify this scenario. The solar activity in 2012 and 2014 was around the maximum of the 24th solar cycle. By combining the imaging and spectral analyses for the three data sets, we successfully separated the contribution of the diffuse emission from the emission of Jupiter’s body (i.e., the aurora and disk emission). The 1–5 keV luminosity of the diffuse emission has been stable and did not vary significantly, and did not simply depend on the solar activity, which is also known to affect the high-energy electron distribution in the Jovian inner magnetosphere scarcely. The luminosity of the body emission both in 0.2–1 and 1–5 keV, in contrast, probably depended on the solar activity and varied by a factor of 2–5. These results strongly supported the inverse-Compton scattering scenario by the ultra-relativistic electrons. In this paper, we estimate spatial and spectral distributions of the inverse-Compton scattering X-rays by Jovian magnetospheric high-energy electrons with reference to the Divine–Garrett model and found a possible agreement in an inner region (≲10 RJ) for the X-ray observations.

中文翻译：

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朱雀对木星漫射硬 X 射线发射的观测

我们报告了朱雀在 2006 年、2012 年和 2014 年对木星的全部三个 X 射线数据集进行系统分析的结果。朱雀在 2006 年发现了木星漫射硬 X 射线发射，当时太阳活动趋于最低限度. 漫射发射在空间上与木星内部磁层一致，并且在光谱上符合表明非热发射的平坦幂律函数。因此，假设提出了一种假设，即木星内部磁层中的超相对论（数十 MeV）电子将太阳可见光子逆康普顿化为 X 射线波段。我们专注于木星漫反射硬 X 射线发射对太阳活动的依赖性，以验证这种情况。2012 年和 2014 年的太阳活动大约是第 24 个太阳周期的最大值。通过结合三个数据集的成像和光谱分析，我们成功地将漫射发射与木星体发射（即极光和圆盘发射）的贡献区分开来。1-5 keV 的漫射光度一直很稳定，没有显着变化，并且不仅仅取决于太阳活动，这也几乎不会影响木星内磁层中的高能电子分布。相比之下，0.2-1 和 1-5 keV 的天体发射光度可能取决于太阳活动，并以 2-5 倍变化。这些结果有力地支持了超相对论电子的逆康普顿散射情景。在本文中，