Here is a summary of the work on SDB2 from tuesday morning the 1st to thursday afternoon the 3rd.
| Elements | Removed (g) | Added (g) |
| Door old | 6144 + 6161 = 12305 | |
| New doors | 3830 + 3854 = 7684 | |
| new bridge | 777 | |
| old bridge (+connector and screw) | 533 | |
| Air box 25 (old B5_PD2) | 854 | |
| Air box 56 (new B5_PD2) | 901 | |
| Air box 01 (old B1p_PD2) | 857 | |
| Air box 63 (new B1p_PD2) | 882 | |
| Beam dump on PD (11 g each) x 6 | 66 | |
| 1 inch mount B1p_M1b | 157 | |
| 1 inch mount B1p_M1b w/ bean dump | 172 | |
| 2 circular beam dumps + spacer (17g each) | 34 | |
| Silicium beam dump w/o glass beam dump | 490 | |
| Silicium beam dump w/ glass beam dump | 501 | |
| Rectangular small beam dump with graduated base (173 g each) x6 | 1038 | |
| Rectangular small beam dump with fork (212 g each) x1 | 212 | |
| Rectangular large beam dump with graduated base x1 | 195 | |
| Total | 15 196 | 12462 |
Difference in weight= -2734g. We added weights of 935g, 943g, 480g, 221g and 223g and removed a small weight of 73g (2729g) in order to recover the same weight as before the intervention .
We replaced B5_PD2 photodiode: Air Box 25 replaced by Air Box 56. B5_PD2 gains and current limit have been adjusted.
We replaced B1p_PD2 photodiode: Air Box 1 replaced by Air Box 63.
We installed a U-shape beam dump on the following photodiodes :
- B5_PD1
- B5_PD2
- B1pP_PD1
- B1p_PD1
- B1p_PD2
- B1_PD3
- B1s_PD1
- B1sP_PD1
All photodiodes that have been removed from their base for the installation of the U-shape beam dump have been tested to check that Vbias can be put On and that the shutter is working.
They have all been tested with light, all are working fine.
Then we started with the beam dumps:
We replaced B1p_M1b mount with the one with a beam dump glued on the side + a beam dump at the back.
Finally we decided to change the splitters.
- B5_M1 ==> W216 (R=0.2) replaced by 36 (R=0.3)
- B5_M4 ==> W208 (R=0.5) replaced by w228 (Rs=1, Tp=1). W208 had wedge on top, W228 now on the right
- B5_M2 ==> W217 (R=0.2) replaced by Adv211 (R=0.5). W217 had wedge on top, Adv211 now on the right
- B1p_M1==> W215 (R=0.2) replaced by Adv212 (R=0.5)
- B1p_M4 ==> W204 (R=0.5) replaced by W215 (R=0.2). wedge changed from right to left
- B1p_M2 ==> W203 (R= 0.5) relpaced by Adv209 (R=0.85)
- B1_M1 ==> AdV210 (R=0.99) replaced by W209 (R=0.999)
- B1p wedges have been reversed: B1p_PBS now on the left and B1p_M5 now on the right
Circular beam dumps have been added in transmission of B1s1_M2 and B1s1_M3 (inside the mount).
We installed 8 glass beam dumps on the reflexion of lenses and ghost beams.
We have displaced B1s_L2 towards east by approximately 20 mm.
Alignmennt check are on-going.
