THE NEW FAST WIRE SCANNER DESIGN FOR THE PSB Dmitry Gudkov Mechanical Engineer Beam Instrumentation Group - Mechanics and Logistics Section In close collaboration with: William Andreazza, Jose Luis Sirvent Blasco, Nicolas Chritin, Bernd Dehning, Jonathan Emery, Paolo Magagnin, Emilien Rigutto, Ray Veness BI Day, 10th of March 2016 BI Day 10 March 2016

Contents Beam wire scanner PS Booster Fast wire scanners at CERN New fast wire scanner for PSB Engineering design of new fast wire scanner for PSB Shaft Angular Position Measurements. Optical Position Sensor Signal acquisition Control and Acquisition electronics Status / Planning Summary BI Day 10 March 2016

Control and acquisition Beam wire scanner Particles generated by the interaction wire - beam Thin carbon wire passes through the particle beam (one out-scan and one in-scan) with linear speed of 20 m/s. Shower of secondary particles is created. Scintillator measures the flux of particles scattered by the interaction of beam and wire. Acquired data is combined with the wire position during the course of the scan. Transverse beam profile is reconstructed. BEAM Vacuum Pipe Scintillator Control and acquisition electronics Optical filters PM current Fork position Photomultiplier Preamplifier BWS system can be divided in three main units: wire moving mechanism in vacuum, detector and control and acquisition Example of beam transversal profile By courtesy of J. Emery More details on next slides BI Day 10 March 2016

PS Booster First beams on 26 May 1972 4 superimposed synchrotron rings Radius 25 m (1/4 of PS) Receive beams of protons from the linear accelerator LINAC 2 at 50 MeV and accelerate them to 1.4 GeV for injection into the Proton Synchrotron (PS). PSB allows the PS to accept over 100 times more protons Picture from http://psb-machine.web.cern.ch/ Picture from http://lhcathome.web.cern.ch/ Picture from http://psb-machine.web.cern.ch/ BI Day 10 March 2016

Fast Wire Scanners at CERN Wire scanners currently in use SPS BWS Prototype (2014) motor which is mounted outside the vacuum pipe motion is then transmitted through bellows inaccuracies due to the relatively complex mechanics motor with vacuum compatible rotor no bellows two supports for the shaft which leads to drum-based design, complicated and expensive for production BI Day 10 March 2016

New Fast Wire Scanners for LIU Program at CERN The fast wire scanner for PSB is a part of LIU program requiring more accurate and faster wire scanners: Plan is to have one design for all the machines. Total 18 scanners will be needed. The machines: PS, PSB, SPS. Installation of 18x instruments is planned for LS2. (B. Dehning: “Specifications and Planning for future wire scanners at CERN”, BWS design review, 18.04.2013)

New fast wire scanner for PSB Comparison with previous Beam Wire Scanners: Direct drive (no bellows used) Compactness biggest vacuum flange CF273 (CF400 for SPS type) Weight 17 kg kinematic assembly (SPS type ~40 kg) 23 kg tank (SPS type ~50 kg) No optical fibers or lenses inside vacuum volume First Prototype in the PSB PSB 4L1 CDD: PSBBWSRA0001 Courtesy of N. Chritin BI Day 10 March 2016

New fast wire scanner for PSB. Engineering Design Motor selection Parameter Value Motor type Frameless PMSM Rotor core material Steel Permanent magnets material Sm2Co17 Wire linear speed, m/s 20 Angular speed, rad/s 133 Acceleration, rad/s2 15711 Inertia of the load, kg x m2 1.1E-03* Radial air gap (stator ID – rotor ED), mm 0.7 Ionizing radiation dose, kGy/year 1 Acceleration profile New motor will be the same in beam wire scanners for PS/SPS/PSB so should provide torque sufficient to accelerate the wire to linear speed 20 m/s in both configurations: 182.5 mm (PS/SPS) and 150 mm (PSB) mm forks; The desired motor should be based on the standard market solution which will be available for many years; The rotor will be located in vacuum and must be vacuum compatible; the use of any glue, other adhesives or insulating materials is not possible. Solid core rotor should be used. The moment of inertia of the rotor should be minimized in order to reduce the required acceleration torque; Features for mounting the rotor on the shaft (key-slots, holes, etc.) should be considered in the design; *-values are optimized during the mechanical design phase BI Day 10 March 2016

New fast wire scanner for PSB. Engineering Design Motor selection Torque required for acceleration of the wire scanner forks in order to achieve the velocity of 20 m/sec on the distance of 60⁰ ( 𝝅 𝟑 ) As a baseline the ALXION 145STK2M-1500 was chosen Peak torque, N.m 55 Rotor Inertia, kg.m^2 1.28E-03 Fork length: R = 150.0 mm Calculation of Required Torque 𝑇=𝐽×𝛼= 1.1𝐸−03+𝐼𝑟 𝑘𝑔. 𝑚 2 ×15711 𝑚 𝑠 2 = = 37.5 N.m (68% of peak torque) Special vacuum compatible version of rotor is developed J – inertia of the load + inertia of the motor rotor Status: delivered at CERN, under validation BI Day 10 March 2016

New fast wire scanner for PSB. Engineering Design The kinematic subassembly unit is designed so that it can be integrated in the following machines: PS, SPS, PSB First prototype will be installed in PSB Sector 4L1 line 3 Beam scans in horizontal plane Kinematic unit – vacuum tank interface (CF273) Viewport interface (CF100) Vacuum pump interface (CF100) RF diagnostics feedthrough interface (CF40/QCF40) Beam Pipe interconnections – conical flanges ø195 mm conical flanges ø195 mm Vacuum pump interface (CF100) RF diagnostics feedthrough interface (CF40/QCF40) Kinematic unit – vacuum tank interface (CF273) Viewport interface (CF100) BI Day 10 March 2016

New fast wire scanner for PSB. Engineering Design Magnetic Brake Motor Stator Fork Wire Viewport 2 possible “home” angular shaft positions Resolver Used to measure angular position of the shaft Shaft Wire diagnostics feedthrough Encoder Disk Encoder disk protection Vacuum chamber Motor rotor BI Day 10 March 2016

New fast wire scanner for PSB. Engineering Design Copper interface Ceramic insulator Wire diagnostics feedthrough 2 x ½ flanges with tapped holes 2 x ½ ring Feedthrough HOSITRAD H100150 MACOR Connector BI Day 10 March 2016

New fast wire scanner for PSB. Engineering Design Stepped Vacuum Chamber CDD: PSBBWSRA0025 The component consists of 3 main parts forming the vacuum volume and 4 optical tube interfaces All the parts except 4 optical tube interfaces are welded together with use of “511” Electron beam welding from vacuum side with full penetration 4 optical tube interfaces are welded with use of “511” Electron beam welding from outside with full penetration Blank: 316LN 3D forged 2 Electron beam welding (full penetration) Wall thickness 0.3 mm Wall thickness 0.3 mm Wall thickness 0.4 mm 3 Electron beam welding (full penetration) 2 2 3 BI Day 10 March 2016

New fast wire scanner for PSB. Engineering Design Resolving potential trapped volumes (virtual leaks) Approved by TE-VSC Hole on the shaft Slot on shaft Slot on the washer Hole on the shaft Slot Hole Hole on the shaft Vented Screw Washer with slot Slot BI Day 10 March 2016

New fast wire scanner for PSB. Engineering Design Vacuum Tank 2 Two side face parts are welded with use of “51” electron beam welding process (from outside) Interfaces tubes and flanges are welded with use of “14” Gas-shielded welding with non consumable electrode from inside or outside with full penetration 2 Electron beam welding (full penetration) 1 2 2 1 2 2 1 CDD: PSBBWSRA0006 2 BI Day 10 March 2016

Shaft Angular Position Measurements. Optical Position Sensor 1310nm continuous wave laser located on the surface Lens detector system, located in the tunnel (link of Single Mode Optical Fibre) Encoder disk (located in vacuum), contain a track, around its circumference, with a pattern of alternated reflective/non reflective slits UHV viewport Focused spot of light of 20um Optical system is able to recover the reflections produced by the slits and couple it back to the fibre optic Reflections are sent back to the surface and directed to the system photodiode (thanks to the optical circulator) By courtesy of J.L. Silvent Blasco BI Day 10 March 2016

Shaft Angular Position Measurements. Optical Position Sensor Optical disk made of Aluminium for lower inertia Slits made by laser engraving Lens system and optical fiber are located outside the vacuum volume Focal distance adjustment possibility by means of fine pitch thread Bakable up to 200 ⁰C Very good roughness is required on the encoder disk face: Ra0.025 BI Day 10 March 2016

pCVD Diamond detector–based secondary shower acquisition system Signal acquisition Scintillators + PMT’s detector–based secondary shower acquisition system pCVD Diamond detector–based secondary shower acquisition system Scintillator Filters PMT Preamplifier Charged particles hit the Scintillator located downstream the BWS tank Photons are generated by scintillator material Photon fluency attenuated by filters and transformed into electric current by photomultiplier tube (PMT) Pre-amplifiers (I-V) for transport through long cables Adjustable PMT and 8 Optical filters. Charged particles hit the gold coated diamond plate located downstream the BWS tank Generation of mobile charges e-h Electrical current when applying HV (Proportional to the Energy) Compact solution (1 cm^2) By courtesy of J. Emery and J.L. Silvent Blasco BI Day 10 March 2016

Control and Acquisition electronics Ethernet Motor feedback into FPGA “Intelligent drive” Scanner control, monitoring and supplies Acquisition and supervision (VME) CPU TIMING HV CTRL Wire diagnostics Optical encoder interface Optical encoder interface Long range resolver interface Fast integration secondary shower 3-phases PWM Control and wire electronics Physical implementation Secondary particles shower acquisition By courtesy of J. Emery BI Day 10 March 2016

Status / Planning All the drawings for main parts are released except assemblies Job request submitted, fabrication planned to be finalized by summer 2016 After fabrication is completed 3 kinematic units will be assembled + 2 vacuum tanks Fabrication starts in March 2016 BI Day 10 March 2016

Summary Design of the new fast wire scanner for PSB is completed Data from fast wire scanner prototype for SPS is used Advantages comparing to prototype for SPS (cantilevered shaft, no drum) More compact design comparing to SPS FWS Less components in vacuum (thanks to lens system outside the tank) Cheaper in production than SPS FWS Production is expected to be finalized by August-September 2016 Assembly and tests are expected in October-November 2016 Installation during EYETS 2016-2017 BI Day 10 March 2016

Thank you very much for your attention! BI Day 10 March 2016

Extra slides BI Day 10 March 2016

Optimization of parts. Shaft Criteria: Taking into account distance between forks, the maximum allowable offset is 16.9 µm. This offset is the combination of torsion, flexion and rigid body. motion of the shaft due to the radial internal clearance of the upper bearing. Shaft movement due to rigid body motion: 𝑒 𝑃𝑆𝐵 = 4.4 µm (value based on bearings data). Envelope for torsion and bending: 16.9-4.4 = 12.5 µm. Analytical pre-dimensioning is performed (XLS), thickness values are analysed in different shaft fractions 3D model created and analysed in Ansys Workbench Region of interest around the wire centre ±20 [mm] Fork Wire Analysis results Flexion: 4.3 µm Rotation between forks: 4.27E-5 rad  corresponding to 7.7 µm offset 4.3 2 + 7.7 2 =8.9 µm < 12.5 µm Acceptable deformation J shaft = 5.43 E-4 kg*m2 By courtesy of P. Magagnin BI Day 10 March 2016

BI Day 10 March 2016

BI Day 10 March 2016

New fast wire scanner for LIU. Series production Planning

Control and Acquisition electronics SFP Ethernet “Intelligent drive” Scanner control, monitoring and supplies Motor feedback into FPGA Acquisition and supervision (VME) CPU T IMING BST receiver HV CTRL SFP Optical link Wire resistivity & Strain gauge External temperature and vibration Optical encoder interface Optical encoder interface Long range resolver interface Fast integration secondary shower Magnetic brake 3-phases PWM Control and wire electronics Physical implementation Secondary particles shower acquisition Electronics for the BWS SPS 02.07.2015 BI-TB

BE-BI-BL Jose Luis Sirvent Blasco (jsirvent@cern.ch) 5. Comparison with operational system: 3.1 LHC_Pilot 1.1e11 PpB 450 GeV (2015_10_23) BE-BI-BL Jose Luis Sirvent Blasco (jsirvent@cern.ch) BI Day 10 March 2016