Chad and I did a leak check on heat shield circuit after target is installed on TM1.The leak detector pumping down is smooth. The base leak rate is 0.0xE-9 atm.cc/sec. The base pressure is 0.0xE-4torr. Chad checked helium flow downstairs and sprayed helium to each joints for 2 seconds.The first joints is good and there is no any response on leak detector.we double checked it again and got the same result. On the second joint, Chad sprayed helium 2second. After 15 second of spraying,the leak detector got a response which climbed to 3.2xE-8 atm.cc/sec max,and back to 2.5 XE-8 atm.cc/sec. Chad tried to tighten the fitting. During his tight, the leak rate response to 7.5x E-8 atm.cc/sec momentarily. After the tightening ,the leak rate back to 0.0x E-9atm.cc/sec whic is the base.So we sprayed the helium to the joint again.This time ,there is no any response on leak detector. We checked this joint  again and got the same result which is no response. Finally, Chad flush the helium around the target for 10 second ,and during 45 sec observation time there is no any response on leak detector. I would say the heat shield circuit is leak tight so far. I will do a helium pressure test on it once the TM1 is moved the CS.