(a) Chamber model built according to the trim size. The flanges for pressing the windows are ignored because of the complex structures. (b) Temperature distribution of the metal chamber caused by heat conduction and convection while the environmental temperature is 293.15 K. The chamber is placed on the platform with one side exposing near the air outlet. That is the reason why the left side (blue) in the graph is cooler than the right side (red), while the upper side (green) is cooler than the lower side (red). (c) The temperature distribution around the cold atoms while the environmental temperature is 293.15 K.