# Ge-experiment training * Wash your hand after the experiment every time! The following topics include: * Liquid-Nitrogen filling and safety in the lab * The knowledge of panels applied to receive the data * Shielding of the Ge-detector ## Liquid-Nitrogen filling and safety ### Principle of pouring out the Liquid-Ne: When we get our loaded Ne back to the lab, the pressure in the bottle is not enough for us to pour it out. We need to wait the evaporation happening in the bottle, and the pressure inner the bottle will get higher with the time going. After 24hr, the pressure will be high enough for us to make the liquid transfer to another bottle.(10Pa at least) #### Process of the storage of liquid-Ne (Storage bucket) 1. Everytime we open up the liquid nitrogen, we need to be careful about *the pressure*. We need to open the vavle of the bucket for releasing the gas upon the liquid to avoid the high-pressure storage causing the dangerous motion of the shell covering the liquid flies out. ( For the safety issue: Get the ring connected to the handle ) 2. Whenever we fill in the liquid Nitrogen, we need to finish setting up the equipment of getting the liquid flow out of the bottle and wait the first 24hr for the enough-pressure stored and the liquid can be extracted after that. 3. Subsequently, the bottle employed to cool down the detector will be filled with the Liquid-Ne after the pressure of already-loaded Liquid-Ne-bottle is enough to be transfered to the experimental one. #### Nitrogen-operation notion (Experimental bucket) 1. Every week we need to fill up the Ne again for the safety and keep it under the low temperature. 2. If we start from the empty circumstance, the 10cm high of the Ne should be filled at the first place ( Use the ruler to check ) , then the second round of filling the Ne should be followed up after 8hr. *Principle: Since the bottle will run out the liquid quickly at the room temperature. We need to wait till the bottle gets equilibrium at 77K, and we can start fill the rest of the space with the liquid. PS1. When deliverying the liquid from one bottle to another one, the frozen pipe used to transfer the liquid should be moved as a whole thing in order to avoid breaking the part of it since under this situation, the pipe is embedded with the frozen water that could be destroyed with the small force. PS2. We need to find out the thing to cover the pre-amplifier when storing the Ne since the low-temperature gas could have the effect on the electronics. #### Pre-amplifier notion 1. Need to connect three basic lines: A. The VGA lines for the power supply B. The 3500V high voltage C. The HV lines to control the HV (detect and response for the high volatge) 2. After the lines written above are well-connected, the time/signal lines can be connected to the amplifier for initiating getting the data. 3. The test lines can give the pulse automatically with the certain amount of the voltage which is used to calibrate the relation between the voltage and the response.