This is the temperature log (temperaturelog.png) of the cryogenic hydrogen target during the cooling test done last night.
The temperature of the heat shield (green line) and the cell (blue line) increased while it went the minimum values at once.
In addition to the overall behaviour, a narrow peak was found (peak,png) in the cell temperature which anti-correlate to that of the heat shield. We consider this is due to the contact between the cell and the heat
shield. 

We could not try liquefying test this morning since the temperature was not enough low.

I would attach the boiling points of several gases in a vacuum (boilingpoinnt.png). We suspect the rebound of the temperature is due to adsorption of vapour such as N2 at 20 K and H20 at 150 K.