We swapped the PMC s/n 2677 for s/n lho006.
The table below summarizes the power levels before and after the PMC swap.
| |
old |
new |
| Ptrans |
1.32 W |
1.42 W |
| Transmission |
85 % |
91.5 % |
| Refl PDDC locked/unlocked |
5.0 % |
4.3 % |
| Loss |
7-8 % |
2-3 % |
| Leakage out of the back |
10 mW |
0.3 mW |
- The power into the PMC (1.67 W) was measured with Scietech bolometer before the first steering PMC mirror. The leakage through the steering mirrors was measured with Ophir power meter to be 12+8 mW. There is also a lens between the mirrors which was not measured.
- The power through the PMC was measured after the doubler pick off (105 mW), steering mirror (4 mW), and lens (not measured).
- The estimated reflection from four lens surfaces is 1-2% hence 1% uncertainty in the losses in the table.
- The beams into the PMC and on REFL PD were realigned. The beams downstream of the PMC are blocked as we did not realigned the PMC and doubler paths.
- The trans PD ND filters were removed. The VDC=1.28 V now.
- The NPRO current is 2.102 A
Atm 1 old
Atm2 new |