The SPEAR3 Upgrade Project at SLAC Catherine Le Cocq, Brian Fuss, Michael Gaydosh Alignment Engineering Group SLAC

SPEAR History 1972: Commissioning as a 2.4 GeV colliding beam facility. 1974: Upgrade to 4 GeV. 1991: Completion of a dedicated electron injector.SPEAR2 operates routinely at 2.3 GeV as a synchrotron radiation source. IWAA97: “Re-Visiting SPEAR After 25 Years” poster by M. Pietryka and all. 1997: Initial upgrade proposal. 1999: Start of SPEAR3 upgrade project. 2004: 3 GeV 100 mA operations. SPEAR= Stanford Positron Electron Asymmetric Ring SLAC-SSRL-SPEAR 3 dedication event of January 29, 2004: “The project was completed three months ahead of schedule, and within its $58M budget.” 10/04/2004 IWAA2004

10/04/2004 IWAA2004

SPEAR3 Goals 3 GeV injection energy (increase from current 2.3 GeV). 18 nm-radian beam emittance (reduction from 160 nm-radian). 100 mA stored beam initially (same as SPEAR 2) with future increases towards 500 mA. emittance = pi*sigmax*sigmax' area of beam in phase space (size and divergence) Decreasing emittance increases the brightness brightness is the # of photons/emittance Local Magnet alignment tolerances: X and y 200 microns, roll 500 microradians Stability of the beam: 5 microns vertically and 15 microns horizontally. 10/04/2004 IWAA2004

SPEAR3 Lattice 18 magnet girders: 18 straight sections: 14 standard cells 4 matching cells 18 straight sections: 12 are 3.1 m 4 are 4.7 m 2 are 7.6 m 234.126 m storage-ring circumference 10/04/2004 IWAA2004

Standard Cell Part 1 10/04/2004 IWAA2004 SPEAR 3 will use 14 new steel girders for the standard cells and 12 new steel girders for the matching cells. Each magnet will be individually supported onto the girder and separately aligned. SPEAR 3 will be equipped with 5 BPMS and 4 corrector magnets per cell. the BPMs are located at each end of the cell, just inboard of each dipole magnet, and near the QFC quadrupole. The BPMs at the ends of the cell will be mechanically isolated by vacuum bellows and mounted on mechanically stable stands with low thermal expansion coefficient. The BPM in the center of the cell will also be mechanically stabilized. 10/04/2004 IWAA2004

Standard Cell Part 2 10/04/2004 IWAA2004 The existing 18 concrete SPEAR 2 magnet girders will be replaced with new steel girders (14 long girders for the standard cells and 12 short girders for the matching cells) to support SPEAR 3 magnets. Each of the 9 m-long steel girders will be supported on three existing 1.5 m long piers, embedded into sandstone beneath the asphalt floor of the ring, and on one new support. Each girder weighs 11,000 lbs and will support a SPEAR 3 magnet and vacuum chamber load of 42,500 lbs for Standard Cells and 24,500 lbs for Matching Cells. This load is 13,000 lbs more than that for SPEAR 2 magnets 10/04/2004 IWAA2004

Standard Cell Part 3 10/04/2004 IWAA2004 Since the support girders themselves are not adjustable, each magnet must have its own adjustment system. A 6- strut, 3-point kinematic support system capable of attaining the 50 pm alignment tolerances will be used for each of the dipole, quadrupole and sextupole magnets. Similar to those used for the ALS and the B-Factory, the support system consists of 3 vertical Y-axis struts, 2 horizontal X-axis struts, and 1 longitudinal Z-axis strut. 10/04/2004 IWAA2004

SPEAR3 Magnets Summary 36 gradient dipoles: 94 quadrupoles: 28 full-length and 8 3/4 lenghth 94 quadrupoles: 4 different lengths: 0.60, 0.50, 0.35 and 0.2 m 72 sextupoles 2 different lengths: 0.25 and 0.21 m 72 dipole correctors 2 injection dipoles 2 injection quadrupoles 1 septum magnet 10/04/2004 IWAA2004

SPEAR3 Beamlines The 7 Insertion Devices beamlines stayed in the same position. The 4 bend magnets beamlines had to be moved. Here are their SPEAR3 characteristics with respect to the center of the upstream straight. α in radian x in mm z in mm BL 1 -0.160000 -105.686 3951.16 BL 2 -0.162375 -108.738 3969.94 BL 3 BL 8 -0.158910 -104.298 3942.52 10/04/2004 IWAA2004

SPEAR3 Timeline April SPEAR2 removal Network 0 April SPEAR2 removal May to mid June Floor construction June 13 to 19 New monuments Network 1 June 26 – July 3 Mark templates Network 2 July 18 – August 1 Support plates August to November Installation Network 3 November 17 to 23 Final alignment December Commissioning 2004 Network 10/04/2004 IWAA2004

Network 0 Description Number of Points 330 Number of Stations 173 Number of Triplets 1356 Number of Height Differences 400 10/04/2004 IWAA2004

Network 0 Composition Booster TC2002 Survey: 9/2001 BTS TC2002 Survey: 3/2002 Building 130 Tracker Survey: 7/2002 SSRL Tracker Survey: 9/2002 SPEAR Ring Tracker Survey: 11/2002 SSRL BL0 TC2002 Survey : 2/2003 10/04/2004 IWAA2004

From SPEAR2 To SPEAR3 SPEAR2 SPEAR3 X Z Z offset = 90000 m X offset = 70000 m Y offset = 2000 m H O = 0.0 m 22 floor SPxxx3D Z X SPEAR3 Z offset = 6000 m X offset = 3000 m Y offset = 500 m H O = 75.791 m 38 floor SMxxFx 10/04/2004 IWAA2004

Network 1 Purpose: Give values to the new SPEAR3 monuments. Description: 166 points: 121 ring monuments including 34 new floor and 4 old floor 45 SSRL and BTS monuments 46 laser tracker stations 611 triplet observations: Distances: 30 µm Horizontal angles: 50 µm / D Vertical angles: 50 µm / D 144 height differences: 50 µm Comment: sigma a posteriori: 0.628621 (distance: 0.859524, horizontal angle: 0.450801, vertical angle: 0.563869, height difference: 0.782653) Weighted datum 10/04/2004 IWAA2004

Network 2 Purpose: Check the new floor stability before the alignment of the support plates. Description: 152 points: 121 ring monuments 31 SSRL and BTS monuments 47 laser tracker stations 676 triplet observations: Distances: 30 µm Horizontal angles: 40 µm / D Vertical angles: 50 µm / D 123 height differences: 50 µm Comment: sigma a posteriori: 0.825995 (distance: 0.832926, horizontal angle: 0.900147, vertical angle: 0.671085, height difference: 0.967139) Free datum 10/04/2004 IWAA2004

Network 3 Purpose: Assign new values to the SPEAR3 monuments before fine tuning all necessary magnets and vacuum chambers. Description: 368 points: 122 ring monuments: 38 floor, 33 aisle, 50 wall and 1 ceiling 45 SSRL monuments 201 magnet TB 40 laser tracker stations 636 triplet observations: Distances: 40 µm Horizontal angles: 40 µm / D Vertical angles: 50 µm / D 303 height differences: 60 µm Comment: sigma a posteriori: 1.046304 (distance: 0.891794, horizontal angle: 0.802313, vertical angle: 1.206194, height difference: 1.245124) Mixed datum with further 3-parameter transformation 10/04/2004 IWAA2004

Datum Controlling Points HRLS010 HRLS090 HRLS100 HRLS105 HBL8N10 SM14F5 SM05F5 HRLN025 Golden Monuments: SM05F5 fixed in Z and X SM14F5 fixed in X 10/04/2004 IWAA2004

First Conclusion December 11, 2003: first complete turn of an injected electron bunch around the ring. By December 15, 2003: the RF system was operational and SPEAR 3 started accumulating beam up to 2 mA. January 22, 2004: the stored current reached 100 mA (maximum current allowed for operation this year). March 8, 2004: BL 9 was opened with first users March 15. By end of March 2004: BL 10, BL 11, BL 6 and BL 5 were opened and ready for users. The project has completely replaced the SPEAR vacuum chamber, magnets, support rafts, RF, power supplies, cable plant and shielding tunnel floor in a 7-month shutdown period that began March 31. Extract from the SPEAR 3 Upgrade Project Close-out Report from April 2004: “Measurements of beam line parameters indicated that the SPEAR 3 optical performance goals were achieved.” 10/04/2004 IWAA2004

2004 Network Purpose: Map the whole ring as part as the 2004 Summer/Fall downtime. Description: 950 points: 143 monuments: 37 floor, 32 aisle, 45 wall, 1 ceiling, 11 others and 17 SSRL points used for height only. 807 magnet TBs 44 laser tracker stations 1809 triplet observations: Distances: 40 µm Horizontal angles: 50 µm / D Vertical angles: 50 µm / D 270 height differences: 50 µm Comment: sigma a posteriori: 0.938286 (distance: 1.287779, horizontal angle: 0.825724, vertical angle: 0.589023, height difference: 0.996919) Mixed datum, offset between the 2 trackers Offset between trackers: -27 microns 10/04/2004 IWAA2004

Floor Monuments Changes November 2003 – October 2004 10/04/2004 IWAA2004

Floor Monuments Changes July 2003- November 2003 10/04/2004 IWAA2004

Network Weak Spot BL11 ID 10/04/2004 IWAA2004

Magnet X as-built 10/04/2004 IWAA2004

Magnet Y as-built 10/04/2004 IWAA2004

Next beam to beamlines will be Monday, October 18, at 6:00AM Final Conclusion Map Z inch X inch Y inch mean 0.001 -0.004 std 0.013 0.011 0.005 Re-Map 0.012 0.007 Quad & Bend 0.000 0.006 Next beam to beamlines will be Monday, October 18, at 6:00AM 10/04/2004 IWAA2004