User name Z. Meziani
Log entry time 23:18:13 on June13,2004
Entry number 125630
keyword=Septa heating test with dummy targetAfter asking permission to the hall coordinator we moved the
target to the 20cm dummy position and started to run at 30uA.
We wanted to see whether the septa would heat up to the same temperature if we used an equivalent thickness of target with an extended geometry. We are still not sure about the thickness of
the foils but at this point we assumed the total thickness is
equivalent to the He4 target.
The result of the heating can be seen in the septa charts.
The temperatures of the right septum during the dummy running
with 30 uA are
Right septum
upper coil Temp.(K): 7.15
lower coil Temp.(K): 6.75
yoke Temp. (K):5.95
to be compared to the He4 running at 30 uA
Right septum
upper coil Temp. (K): 7.70
lower coil Temp. (K): 7.50
yoke Temp. (K): 6.25
The left septum temperatures are lower but can be scaled looking at the charts.
If the thickness of the dummy target is truly equivalent in radiation length as the He4 target it suggests that perhaps the background is
coming from something around the target but not the Helium itself.
It would be important to run the beam through the real target cell but emptied of He4. If running at 30 uA shows the same heating it means the walls of the target are perhaps responsible for the large background and heating.
We need to check the thickness of the dummy target with Dave Meekins.
The suspicion now is that effects on the body of the target is the cause for Septa heating.
To be followed on Monday.
FIGURE 1
FIGURE 2
