摘要
雷射冷凝是一項研究原子分子相互間運動的技術。而我們在銫原子的研究上就是使用磁光陷阱(MOT)來捕捉並研究其物理特性。
在這實驗中我們嘗試對於被捕捉的銫原子團做溫度上的量測，而採用的方法為分析自由飛行所花的時間並觀測其飛行距離，由此可得其飛行速度而進一步得知相對應的溫度。
使用類比型CCD所得的分析數值銫原子在光學糖蜜下的速度為1.5㎝/s，相對應的溫度為3.6μK。但是在時間的解析度不足和擷取分析上有可能為觀測軸切面上的速度投影而已，如此所得的相對溫度數值應較其真實溫度小。因此未來實驗上會改進分析程式與擷取影像技術，而得到正確的溫度分布。

Abstract
Laser cooling and trapping is a novel technique to manipulate the neutral atoms and molecules. The cesium atom was loaded into the magneto-optical trap (MOT) for studying the physical properties of atoms at low temperature.
In this experiment, the temperature of cesium atoms within the optical molasses was taken by the time of flight method (TOF). The position was recorded when they were expanding inside the optical molasses. The velocity and therefore the temperature of cesium atoms can be calculated.
The velocity was about 1.5㎝/s corresponding to the temperature was about 3.6μK. This temperature is under estimate due to the time resolution (33ms) and the projection of atom cloud into the transverse section of the observe axis. We tried a digital CCD camera and measured the right timing from the computer controlled time sequence. However, no significant results yet.

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