（162173）1999 JU3的光学性质：为JAXA Hayabusa 2号样品返回任务做准备
Optical Properties of (162173) 1999 JU3: In Preparation for the JAXA Hayabusa 2 Sample Return Mission
摘要：
我们研究了（162173）1999 JU 3的星等-相位关系，这是JAXA隼鸟2号采样返回任务的目标小行星。我们最初采用了国际天文学联合会的H-G形式主义，但发现它不太适合使用一组参数。为了改善拟合不足，我们采用了两个光度函数，舍甫琴科和哈普克函数。利用Shevchenko函数，我们发现星等-相位关系在较宽的相位角范围内（α = 5-75度）表现出线性行为，并且在α < 5度时显示出弱的非线性逆增亮，从而提供了更可靠的Hv = 19.25 +- 0.03的绝对星等。相位斜率（0.039 ± 0.001 mag/deg）和对冲效应幅度（参数为α =0.3 deg与α =5 deg的强度之比，I（0.3）/I（5）=1.31 ± 0.05）与典型的C-型小行星一致。我们还试图确定Hapke模型的参数，这些参数适用于使用Hayabusa 2机载相机构建表面反射率图。虽然我们不能约束Hapke参数的全部集合，但我们得到了可能的值，w=0.041，g=-0.38，B 0 =1.43，h=0.050，假设表面粗糙度参数θ =20 °。通过将我们的光度研究与小行星的热模型（Mueller等人正在准备）相结合，我们得到了pv = 0.047 +- 0.003的几何常数，相位积分q = 0.32 +- 0.03，邦德常数AB = 0.014 +- 0.002，这与普通C-型小行星的数值相当。
英文摘要：
We investigated the magnitude-phase relation of (162173) 1999 JU3, a target asteroid for the JAXA Hayabusa 2 sample return mission. We initially employed the international Astronomical Union's H-G formalism but found that it fits less well using a single set of parameters. To improve the inadequate fit, we employed two photometric functions, the Shevchenko and Hapke functions. With the Shevchenko function, we found that the magnitude-phase relation exhibits linear behavior in a wide phase angle range (alpha = 5-75 deg) and shows weak nonlinear opposition brightening at alpha< 5 deg, providing a more reliable absolute magnitude of Hv = 19.25 +- 0.03. The phase slope (0.039 +- 0.001 mag/deg) and opposition effect amplitude (parameterized by the ratio of intensity at alpha=0.3 deg to that at alpha=5 deg, I(0.3)/I(5)=1.31+-0.05) are consistent with those of typical C-type asteroids. We also attempted to determine the parameters for the Hapke model, which are applicable for constructing the surface reflectance map with the Hayabusa 2 onboard cameras. Although we could not constrain the full set of Hapke parameters, we obtained possible values, w=0.041, g=-0.38, B0=1.43, and h=0.050, assuming a surface roughness parameter theta=20 deg. By combining our photometric study with a thermal model of the asteroid (Mueller et al. in preparation), we obtained a geometric albedo of pv = 0.047 +- 0.003, phase integral q = 0.32 +- 0.03, and Bond albedo AB = 0.014 +- 0.002, which are commensurate with the values for common C-type asteroids.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
