概括
南极冰非常透明,可见光的吸收长度为59米. 这种在现场测量的极端清晰度超过了实验室冰,并与超纯水质相美.
科学领域:
- 冰川学的冰川学
- 光学物理学 光学物理学
- 中微子天文学 中微子天文学
背景情况:
- 南极深层冰的光学特性对于像南极子和中微子探测器阵列 (AMANDA) 这样的中微子探测器至关重要.
- 了解冰中的光吸收和散射对于解释切伦科夫辐射信号至关重要.
研究的目的:
- 测量在南极冰层深处可见光的 in situ 吸收和散射长度.
- 为了将这种冰的光学特性与超纯水和实验室冰进行比较.
主要方法:
- 在现场测量使用AMANDA中微子探测器的激光校准系统.
- 在0.8至1公里的深度进行调查,重点关注可见光 (约. 515 nm) 的距离.
主要成果:
- 冰表现出内在的极端透明度,测量的吸收长度为59±3米.
- 这种吸收长度相当于超纯水,是最好的实验室冰的两倍多.
- 由于气泡的散射被观察到,反向的散射长度与深度线性减少.
结论:
- 南极的深冰是光线传播的非常透明的介质.
- 空气泡的存在会影响光子散射,但冰的内在透明度是显著的.
- 这些发现验证了在中微子天文学中使用深冰进行光学测量.
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