Applied Geodesy Group Survey and Alignment of the ILC An approach to cost calculation and network simulations VLCW06 Vancouver, British Columbia, July 2006 Johannes Prenting, Markus Schlösser, DESY

J. Prenting, M. DESYJuly 2006 INTRODUCTION ACCURACY CALCULATION S URVEY & A LIGNMENT I SSUES FOR I LC COST CALCULATION LC Survey Challenge  Survey = multi step process with single tolerance budget driven by accelerator physics:  component construction  component fiducialisation  component survey  machine alignment Components Survey:  200µm vertical, 500µm horizontal = our slice of tolerance budget  over some 100m = O (betatron) wavelenght INTRODUCTION

J. Prenting, M. DESYJuly 2006 INTRODUCTION ACCURACY CALCULATION S URVEY & A LIGNMENT I SSUES FOR I LC COST CALCULATION accuracy requirements met? possible survey solution for XFEL economic requirements met? survey solution found no yes no yes solution unusable solution unusable ILC INTRODUCTION

J. Prenting, M. DESYJuly 2006 INTRODUCTION ACCURACY CALCULATION S URVEY & A LIGNMENT I SSUES FOR I LC COST CALCULATION accuracy requirements met? possible survey solution for XFEL economic requirements met? survey solution found no yes no yes solution unusable solution unusable ILC Accuracy demands: Linac: transversal : s module =0.5mm, s cavity =s quad =0.3mm, s BPM = 0.3mm vertical : s module =0.2mm, s cavity =s quad =0.2mm, s BPM = 0.2mm over a range of some 100m length. Injector: ?? damping rings: ?? beam delivery system: ?? final focus: ?? machine detector interface: ?? INTRODUCTION

J. Prenting, M. DESYJuly 2006 INTRODUCTION ACCURACY CALCULATION S URVEY & A LIGNMENT I SSUES FOR I LC COST CALCULATION accuracy requirements met? possible survey solution for XFEL economic requirements met? survey solution found no yes no yes solution unusable solution unusable ILC Accuracy demands: Linac: transversal : s module =0.5mm, s cavity =s quad =0.3mm, s BPM = 0.3mm vertical : s module =0.2mm, s cavity =s quad =0.2mm, s BPM = 0.2mm over a range of some 100m length. Injector: ?? damping rings: ?? beam delivery system: ?? final focus: ?? machine detector interface: ?? What can we achieve with classical survey methods? INTRODUCTION

J. Prenting, M. DESYJuly 2006 INTRODUCTION ACCURACY CALCULATION S URVEY & A LIGNMENT I SSUES FOR I LC COST CALCULATION ACCURACY CALCULATION Simulation of an ILC-tunnel network The following basic assumptions have been made: NO refraction (!), only the geometrical standard deviations have been taken into account. Refraction can – of course – make a much bigger error than shown here. Lasertracker: sigma horizontal=0.15mgon, sigma vertical=0.15mgon, sigma distance=0.015mm Tacheometer: sigma horizontal=0.3mgon, sigma vertical=0.3mgon, sigma distance=0.15mm The FULL tunnel network consists of “rings” of 12 reference points (figure 1) which are located in cross-sections of the tunnel. These rings are positioned every 10m through the whole tunnel. Instrument stands are in the middle between two rings (figure2) Observations are made from each instrument stand to the next two rings forward and backward. So one instrument stand generally consists of 48 measured points (figure 2) or 3*48=144 observations (horizontal and vertical angle and distance). Reference „rings“, equidistance 10m observations figure 2: ground plan (FULL) with reference rings, instrument stands and observations reference points lasertracker or tacheometer figure 1: cross section of tunnel (FULL)

J. Prenting, M. DESYJuly 2006 INTRODUCTION ACCURACY CALCULATION S URVEY & A LIGNMENT I SSUES FOR I LC COST CALCULATION ACCURACY CALCULATION Simulation of an ILC-tunnel network When looking at existing accelerator tunnels the assumption, that a complete cross-section is available for the reference networks, seems rather optimistic. A more realistic approach would be that one half of the tunnel is permanently blocked by other installations. That leads to the following HALF tunnel network: reference „rings“, equidistance 10mobservations other installations lasertracker or tacheometer reference points figure 3: cross section of tunnel (HALF) and instrument figure 4: ground plan (HALF) with reference rings, instrument stands and observations

J. Prenting, M. DESYJuly 2006 INTRODUCTION ACCURACY CALCULATION S URVEY & A LIGNMENT I SSUES FOR I LC COST CALCULATION ACCURACY CALCULATION Tacheometer: sigma h=0,3mgon, sigma v=0,3mgon, sigma d=0,15mm full X-section available, (3mx3m)

J. Prenting, M. DESYJuly 2006 INTRODUCTION ACCURACY CALCULATION S URVEY & A LIGNMENT I SSUES FOR I LC COST CALCULATION ACCURACY CALCULATION Tacheometer: sigma h=0,3mgon, sigma v=0,3mgon, sigma d=0,15mm half X-section available, (1.5mx3m)

J. Prenting, M. DESYJuly 2006 INTRODUCTION ACCURACY CALCULATION S URVEY & A LIGNMENT I SSUES FOR I LC COST CALCULATION ACCURACY CALCULATION Lasertracker: sigma h=0,15mgon, sigma v=0,15mgon, sigma d=0,015mm full X-section available, (3mx3m)

J. Prenting, M. DESYJuly 2006 INTRODUCTION ACCURACY CALCULATION S URVEY & A LIGNMENT I SSUES FOR I LC COST CALCULATION ACCURACY CALCULATION Lasertracker: sigma h=0,15mgon, sigma v=0,15mgon, sigma d=0,015mm half X-section available, (1.5mx3m)

J. Prenting, M. DESYJuly 2006 INTRODUCTION ACCURACY CALCULATION S URVEY & A LIGNMENT I SSUES FOR I LC COST CALCULATION angle of refraction mit = a = konstant n = refractive index  = local refractive coefficient  = f(P,T, )  f( ) approximation equations thus and Achievable accuracy with conventional methods in this application mainly depends on the ACCURACY CALCULATION

J. Prenting, M. DESYJuly 2006 INTRODUCTION ACCURACY CALCULATION S URVEY & A LIGNMENT I SSUES FOR I LC COST CALCULATION Numerical examples for various distance angular error lateral error angular error lateral error lateral refraction Comparison with altimetry Standard solution to minimize effects of refraction: monitoring pillars alternating on either side of the tunnel. =>Conventional optical methods not suitable here. ACCURACY CALCULATION

J. Prenting, M. DESYJuly 2006 INTRODUCTION ACCURACY CALCULATION S URVEY & A LIGNMENT I SSUES FOR I LC COST CALCULATION  Complex & irregular layout of machine:  Horizontally and vertically curved sections, (R min >500m)  Some sections geometrically straight, others following geoid  Sections with significant slopes  Many different sections (Linac, DR, BDS, FF, MDI)  Possibly various beamlines in one tunnel  Temp. & pressure gradients in tunnel  Very tight working space (1m wide)  Space serves as emergency escape route  Optical Survey methods are not precise enough for reference structure  Need new instrument  RTRS (Rapid Tunnel Reference Surveyor) Provides regular reference structure Uses regular markers at tunnel wall No long-term stable (>months) reference monuments at O(10  m) level Need frequent surveys Need automated process LC Survey Challenge Best solution is to split up the survey procedure into a reference survey (along the tunnel) and a stake out  transfers coordinates to the machine over short distances across the tunnel ACCURACY CALCULATION CONSEQUENCES

J. Prenting, M. DESYJuly 2006 INTRODUCTION ACCURACY CALCULATION S URVEY & A LIGNMENT I SSUES FOR I LC COST CALCULATION accuracy requirements met? possible survey solution for XFEL economic requirements met? survey solution found no yes no yes solution unusable solution unusable ILC Accuracy demands: Linac: transversal : s module =0.5mm, s cavity =s quad =0.3mm, s BPM = 0.3mm vertical : s module =0.2mm, s cavity =s quad =0.2mm, s BPM = 0.2mm over a range of some 100m length. LiCAS: ~40µm transversal, ~100µm vertical ACCURACY CALCULATION CONSEQUENCES

J. Prenting, M. DESYJuly 2006 INTRODUCTION ACCURACY CALCULATION S URVEY & A LIGNMENT I SSUES FOR I LC COST CALCULATION Cost calculation (of reference system) TCO Ref = R acc n surv L acc T sd (k sd + C surv ) + I surv + M surv R acc :Lifetime of accelerator [years] n surv :Number of surveys per year [1/year] L acc :Length of accelerator [km] T sd :SD-time required for 1 km survey [days/km] k sd :cost per shutdowntime [€/day] C surv :cost of survey team(s) [€/day] I surv :Investment costs for survey system [€] M surv :Maintenance costs for Survey instruments [€] COST CALCULATION

J. Prenting, M. DESYJuly 2006 INTRODUCTION ACCURACY CALCULATION S URVEY & A LIGNMENT I SSUES FOR I LC COST CALCULATION Cost calculation (conventional optical survey w. Lasertracker, 10 teams) R acc :20 years n surv :1.2 / year L acc :33 km T sd :5 days/km k sd : € / day C surv :1.120 € / day I surv : € / team M surv :2.500 € /instr./year TCO Ref = 322 Mill. € (& 1.7 years downtime) COST CALCULATION

J. Prenting, M. DESYJuly 2006 INTRODUCTION ACCURACY CALCULATION S URVEY & A LIGNMENT I SSUES FOR I LC COST CALCULATION TCO Ref = 90 Mill. € (& 99 days downtime) Cost calculation (RTRS, 1 train) TCO Ref = 0.8 Mill. € days downtime Cost calculation (conventional optical survey w. Lasertracker, 40 teams) COST CALCULATION

J. Prenting, M. DESYJuly 2006 INTRODUCTION ACCURACY CALCULATION S URVEY & A LIGNMENT I SSUES FOR I LC COST CALCULATION accuracy requirements met? possible survey solution for XFEL economic requirements met? survey solution found no yes no yes solution unusable solution unusable ILC Economic requirements: RTRS Accuracy demands: Linac: transversal : s module =0.5mm, s cavity =s quad =0.3mm, s BPM = 0.3mm vertical : s module =0.2mm, s cavity =s quad =0.2mm, s BPM = 0.2mm over a range of some 100m length. LiCAS: ~40µm transversal, ~100µm vertical -> see talk of G.Grzelak COST CALCULATION

Applied Geodesy Group Survey and Alignment of the ILC An introduction to the concept and open questions Johannes Prenting, Markus Schlösser, DESY Thnx for your attention ! VLCW06 Vancouver, British Columbia, July 2006