1. LHCb MUON - ADDITIONNAL SHIELD BEHIND M5 – UNIT AREA 600 700 Dimensions of 1 iron brick  100 x 100 x 200 mm3 1 ROW of 1200 mm length  12 iron blocks / row Shielding area 1200 x 700 mm2  7 x 12 = 84 iron blocks Shielding area 4800 x 700 mm2  4 x 84 = 336 iron blocks Weight of 1 iron brick  15 kg Total weight of shield  5040 kg 200 16 January 20121D.LACARRERE

2. ADDITIONNAL IRON SHIELD BEHIND MUON CHAMBERS M5 BELT (*) IRON BLOCKS MF4 16 January 20122D.LACARRERE (*) Belt in order to fix the iron blocks – not yet defined NO SCALE 2400 700

3. 16 January 2012D.LACARRERE3 STATUS 5 DECEMBER 2011 (in brief) - IRON BLOCKS : ~ 400 blocks available (250 at Pit2 + 150 at Pit8) ; non “TFA” - RP CHECK : Ask for authorization to blast the blocks – corroded surfaces - on going - SURFACE TREATMENT (in preparation) : a) blasting with special sand (garnet 30-60 mesh) – DAI 479609 08/11/2011 b) painting before x-mas – drying during Christmas break. - SCHEDULE : 1 - Blasting week 12/12/2011 2 - Painting week 19/12/2011 3 - Installation top of MF4 – mid-January 2012 (to be specified by Muon Group)

4. 16 January 2012D.LACARRERE4 16 JANUARY 2012 (in brief) - IRON BLOCKS : ~ 363 blocks available (208 from Pit2 + 155 from Pit8) ready to send to the firm for cleaning & painting just before X-MAS; BUT  Unfortunately the last radiological check performed on 19 Dec. 2011 revealed that a few blocks from the batch Pit2 were TFA (unexpected ).  Transfer to Firm (MENONI -74 SCIENTRIER) scheduled for 20/12/2011 was stopped.  Systematic RP control of all the blocks (all faces) was required par the CERN/RP Group.  Systematic RP Control performed by RP Group on 10 January 2012 at Pit8 ; 46 blocks from the batch (Pit 2) were classified TFA as suspected before X-MAS; in order to replace these TFA blocks 50 additional blocks (non-TFA) were recovered (from BA7 & Area 19)  NOW we have 396 blocks dedicated to MUON filter, available for cleaning & painting. Transfer of the 396 blocks to be treated outside CERN (MENONI Company) was performed on 16 January 2012 (am) as scheduled. Return of blocks to CERN : Progressively, last batch expected for Fri. 10 February 2012. Installation behind M5 (end) : Week 07 from 13 to 17 Feb. 2012.