The HiLumi LHC Design Study is included in the High Luminosity LHC project and is partly funded by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement Presented by P. Fessia HL-LHC: Civil engineering why

DFHX DFHM Q1-Q2a-Q2b-Q3-CP-D1 Q6 Q7 Q5 D2 Q4 2x13KA DQR RR Pt1 & Pt 5: cryogenic concept and magnet powering DQS DQR DQS CC QURC+QUI 1.9K Cold Box New cavern QRL DFBAJ DFXJ DFMJ VB DS Existing EXP. CRYO POWER CONVERTERS 4.5 K Cold box WARM COMPRESSORS

Q1-Q2a-Q2b-Q3-CP-D1 Q6 Q7 Q5 D2 Q4 2x13KA RR QURC+QUI New cavern QRL VB DS DFBAJ DFXJ DFMJ CC Loads + circulator + tetrodes HVPS RF control RF control Central RF control Central RF control Pt1 & Pt 5: crab cavity RF services concept

Inventory of space requirement IP SURFACESURFACE SURFACESURFACE TUNNELTUNNEL TUNNELTUNNEL CONNCONN CONNCONN Warm compressors and 4.5 K cold box 1000 m 2 Warm compressors and 4.5 K cold box 1000 m K Cold box 300 m K Cold box 300 m 2 Power converters 320 m 2 Power converters 320 m 2 Power converters 320 m 2 Power converters 320 m 2 RF crab cavity equipment 200 m 2 RF crab cavity equipment 200 m 2 RF crab cavity equipment 200 m 2 RF crab cavity equipment 200 m 2 IP SURFACESURFACE SURFACESURFACE TUNNELTUNNEL TUNNELTUNNEL CONNCONN CONNCONN Warm compressors and 4.5 K cold box 1000 m 2 Warm compressors and 4.5 K cold box 1000 m K Cold box 300 m K Cold box 300 m 2 RF crab cavity equipment 200 m 2 RF crab cavity equipment 200 m 2 RF crab cavity equipment 200 m 2 RF crab cavity equipment 200 m 2 Baseline Option Power converters 320 m 2 Power converters 320 m 2 Power converters 320 m 2 Power converters 320 m 2

5 UJ 13 UJ 17 RI132 RI171 IP 1 RF building (left side) Service tunnel Cryogenic cavern + 5 cores shaft building SD Warm comp. Powering RF building (right side) 3x Service junction tunnel Junction tunnel shaft to cavern Point 1 - BASELINE : allocation of volumes to technical equipment and systems Cryogenics RF Powering

< N (10) (11) (12) (14) Shaft (14) New fenced limit Car park Landscaping Area New fenced limit Landscaping Area Car park Foot path deviation 15 Shaft access and 4.5 K cold box RF building (left side) New access road needed RF building (right side) Warm compressors Powering

7 Shaft access and 4.5 K cold box Warm comp. Point 1: OPTION Connection with existing UJ13 and UJ17 Cryogenics RF Powering

N (10) (11) Shaft New fenced limit Foot path deviation Car park Landscaping Area N New fenced limit Shaft access and 4.5 K cold box Warm compressors

Point 5: BASELINE surface installation Cryogenics RF Powering

HL-LHC C&S Review #1 – March 2015 Powering 10 Point 5 Baseline surface building Shaft access and 4.5 K cold box Warm compressors RF building (left side) RF building (right side)

Point 5: OPTION underground installation Cryogenics Powering Crab Cavity DFXJ5LDFXJ5R UJ57 UJ53 PM5 4 USC55 RF

12 HL-LHC C&S Review #1 – March 2015 Point 5 Option surface building Shaft access and 4.5 K cold box Warm compressors

13 Conclusions HL-LHC civil engineering underground works are needed for technical reasons. Need to install 1.9 K cold box underground. No volume available. This goes with a shaft and a tunnel/distribution tunnel. This “basic requirement ” fit HL-LHC baseline The underground options do not increase the length of the tunnels to be excavated but manly their section. Therefore the time needed for the work underground will be longer. Difference to be evaluated by CE. From the point of view of costs the difference between the two is in the noise of budget error, but it allows simplification of installation, reduction of CE work during LS3, reduction of LHC tunnel disruption and cost reduction of equipment mainly SC link. It also reduces the surface footprint HL-LHC C&S Review #1 – March 2015