Survey and Alignment of the ILC An approach

Survey and Alignment of the ILC An approach to cost calculation and network simulations Johannes Prenting, Markus Schlösser, DESY Applied Geodesy Group § VLCW 06 Vancouver, British

SURVEY & ALIGNMENT ISSUES FOR I LC LC Survey Challenge INTRODUCTION § Survey = multi step process with single tolerance budget driven by accelerator physics: § § ACCURACY CALCULATION component construction component fiducialisation component survey machine alignment Components Survey: § 200µm vertical, 500µm horizontal = our slice of tolerance budget § over some 100 m = O (betatron) wavelenght COST CALCULATION J. Prenting, M. Schlösser Geodesy @ DESY July 2006

SURVEY & ALIGNMENT ISSUES FOR I LC possible survey solution for ILC XFEL INTRODUCTION accuracy requirements met? ACCURACY CALCULATION solution unusable no solution unusable yes economic requirements met? COST CALCULATION no yes survey solution found J. Prenting, M. Schlösser Geodesy @ DESY July 2006

SURVEY & ALIGNMENT ISSUES FOR I LC possible survey solution for ILC XFEL Accuracy demands: Linac: INTRODUCTION transversal : s module =0. 5 mm, s cavity =s quad=0. 3 mm, s BPM = 0. 3 mm accuracy requirements met? vertical : solution s module =0. 2 mm, s cavity =s quad=0. 2 mm, s BPM = 0. 2 mm no unusable over a range of some 100 m length. ACCURACY CALCULATION yes Injector: ? ? damping rings: ? ? economic requirements met? solution beam delivery system: ? ? no unusable final focus: ? ? machine detector interface: ? ? COST CALCULATION yes survey solution found J. Prenting, M. Schlösser Geodesy @ DESY July 2006

SURVEY & ALIGNMENT ISSUES FOR I LC possible survey solution for ILC XFEL Accuracy demands: Linac: INTRODUCTION transversal : s module =0. 5 mm, s cavity =s quad=0. 3 mm, s BPM = 0. 3 mm accuracy requirements met? vertical : solution s module =0. 2 mm, s cavity =s quad=0. 2 mm, s BPM = 0. 2 mm no unusable over a range of some 100 m length. ACCURACY CALCULATION yes Injector: ? ? damping rings: ? ? economic requirements met? solution beam delivery system: ? ? no unusable final focus: ? ? machine detector interface: ? ? COST CALCULATION yes survey solution found J. Prenting, M. Schlösser What can we achieve with classical survey methods? Geodesy @ DESY July 2006

SURVEY & ALIGNMENT ISSUES FOR I LC Simulation of an ILC-tunnel network The following basic assumptions have been made: INTRODUCTION 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. 15 mgon, sigma vertical=0. 15 mgon, sigma distance=0. 015 mm Tacheometer: sigma horizontal=0. 3 mgon, sigma vertical=0. 3 mgon, sigma distance=0. 15 mm ACCURACY CALCULATION 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 10 m through the whole tunnel. Instrument stands are in the middle between two rings (figure 2) 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). lasertracker or tacheometer reference points COST CALCULATION Reference „rings“, equidistance 10 m figure 1: cross section of tunnel (FULL) J. Prenting, M. Schlösser observations figure 2: ground plan (FULL) with reference rings, instrument stands and observations Geodesy @ DESY July 2006

SURVEY & ALIGNMENT ISSUES FOR I LC Simulation of an ILC-tunnel network INTRODUCTION ACCURACY CALCULATION COST CALCULATION 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: lasertracker or tacheometer reference points other installations figure 3: cross section of tunnel (HALF) and instrument reference „rings“, equidistance 10 m observations figure 4: ground plan (HALF) with reference rings, instrument stands and observations J. Prenting, M. Schlösser Geodesy @ DESY July 2006

SURVEY & ALIGNMENT ISSUES FOR I LC Tacheometer: sigma h=0, 3 mgon, sigma v=0, 3 mgon, sigma d=0, 15 mm INTRODUCTION full X-section available, (3 mx 3 m) ACCURACY CALCULATION COST CALCULATION J. Prenting, M. Schlösser Geodesy @ DESY July 2006

SURVEY & ALIGNMENT ISSUES FOR I LC Tacheometer: sigma h=0, 3 mgon, sigma v=0, 3 mgon, sigma d=0, 15 mm INTRODUCTION half X-section available, (1. 5 mx 3 m) ACCURACY CALCULATION COST CALCULATION J. Prenting, M. Schlösser Geodesy @ DESY July 2006

SURVEY & ALIGNMENT ISSUES FOR I LC Lasertracker: sigma h=0, 15 mgon, sigma v=0, 15 mgon, sigma d=0, 015 mm INTRODUCTION full X-section available, (3 mx 3 m) ACCURACY CALCULATION COST CALCULATION J. Prenting, M. Schlösser Geodesy @ DESY July 2006

SURVEY & ALIGNMENT ISSUES FOR I LC Lasertracker: sigma h=0, 15 mgon, sigma v=0, 15 mgon, sigma d=0, 015 mm INTRODUCTION half X-section available, (1. 5 mx 3 m) ACCURACY CALCULATION COST CALCULATION J. Prenting, M. Schlösser Geodesy @ DESY July 2006

SURVEY & ALIGNMENT ISSUES FOR I LC Achievable accuracy with conventional methods in this application mainly depends on the angle of refraction INTRODUCTION mit = a = konstant n = refractive index = local refractive coefficient ACCURACY CALCULATION = f(P, T, ) f( ) approximation equations COST CALCULATION thus J. Prenting, M. Schlösser and Geodesy @ DESY July 2006

SURVEY & ALIGNMENT ISSUES FOR I LC Numerical examples for various INTRODUCTION lateral refraction distance angular error Comparison with altimetry lateral error angular error lateral error ACCURACY CALCULATION COST CALCULATION Standard solution to minimize effects of refraction: monitoring pillars alternating on either side of the tunnel. =>Conventional optical methods not suitable here. J. Prenting, M. Schlösser Geodesy @ DESY July 2006

SURVEY & ALIGNMENT ISSUES FOR I LC LC Survey Challenge § § INTRODUCTION ACCURACY CALCULATION CONSEQUENCES Complex & irregular layout of machine: § § § Horizontally and vertically curved sections, (Rmin>500 m) 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 (1 m wide) Space serves as emergency escape route 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 Optical Survey methods are not precise enough for reference structure Need new instrument RTRS (Rapid Tunnel Reference Surveyor) COST CALCULATION • • Provides regular reference structure Uses regular markers at tunnel wall • No long-term stable (>months) reference monuments at O(10 mm) level • Need frequent surveys • Need automated process J. Prenting, M. Schlösser Geodesy @ DESY July 2006

SURVEY & ALIGNMENT ISSUES FOR I LC possible survey solution for ILC XFEL INTRODUCTION Accuracy demands: Linac: transversal : s module =0. 5 mm, s cavity =s quad=0. 3 mm, s BPM = 0. 3 mm accuracy requirements met? solution vertical : s module =0. 2 mm, s cavity =s quad=0. 2 mm, s BPM = 0. 2 mm no unusable over a range of some 100 m length. Li. CAS: ~40µm transversal, ~100µm vertical ACCURACY CALCULATION yes CONSEQUENCES economic requirements met? COST CALCULATION no solution unusable yes survey solution found J. Prenting, M. Schlösser Geodesy @ DESY July 2006

SURVEY & ALIGNMENT ISSUES FOR I LC Cost calculation (of reference system) INTRODUCTION TCORef = Racc nsurv Lacc Tsd (ksd + Csurv) + Isurv + M surv ACCURACY CALCULATION COST CALCULATION Racc : nsurv : Lacc : Tsd : ksd : Csurv : Isurv : M surv : Lifetime of accelerator [years] Number of surveys per year [1/year] Length of accelerator [km] SD-time required for 1 km survey [days/km] cost per shutdowntime [€/day] cost of survey team(s) [€/day] Investment costs for survey system [€] Maintenance costs for Survey instruments [€] J. Prenting, M. Schlösser Geodesy @ DESY July 2006

SURVEY & ALIGNMENT ISSUES FOR I LC Cost calculation (conventional optical survey w. Lasertracker, 10 teams) INTRODUCTION ACCURACY CALCULATION COST CALCULATION Racc nsurv Lacc Tsd ksd Csurv Isurv Msurv : : : : : 20 years 1. 2 / year 33 km 5 days/km 800. 000 € / day 1. 120 € / day 100. 000 € / team 2. 500 € /instr. /year TCORef = 322 Mill. € (& 1. 7 years downtime) J. Prenting, M. Schlösser Geodesy @ DESY July 2006

SURVEY & ALIGNMENT ISSUES FOR I LC Cost calculation (conventional optical survey w. Lasertracker, 40 teams) INTRODUCTION TCORef = 90 Mill. € (& 99 days downtime) ACCURACY CALCULATION Cost calculation (RTRS, 1 train) COST CALCULATION TCORef = 0. 8 Mill. € + 170 days downtime J. Prenting, M. Schlösser Geodesy @ DESY July 2006

SURVEY & ALIGNMENT ISSUES FOR I LC possible survey solution for ILC XFEL INTRODUCTION Accuracy demands: Linac: transversal : s module =0. 5 mm, s cavity =s quad=0. 3 mm, s BPM = 0. 3 mm accuracy requirements met? solution vertical : s module =0. 2 mm, s cavity =s quad=0. 2 mm, s BPM = 0. 2 mm no unusable over a range of some 100 m length. Li. CAS: ~40µm transversal, ~100µm vertical -> see talk of G. Grzelak ACCURACY CALCULATION yes Economic requirements: economic requirements met? no solution unusable RTRS COST CALCULATION yes survey solution found J. Prenting, M. Schlösser Geodesy @ DESY July 2006

Survey and Alignment of the ILC An introduction to the concept and open questions Johannes Prenting, Markus Schlösser, DESY Thnx for your attention ! Applied Geodesy Group § VLCW 06 Vancouver, British