ATF 2 Magnets Measurements of the ATF 2

ATF 2 Magnets Measurements of the ATF 2 FF sextupoles and status report 26 th/27 th August 2008 Cherrill Spencer, Magnet Designer and member of ATF 2 Magnet Group 26/27 th August 2008 ATF 2 FF Sextupoles Msts

ATF 2 Magnets Reporting tonight on the last three ATF 2 magnets I have responsibility for: SF 6, SF 5 and SD 4. Their beamline positions are shown in the diagram above. They will have cavity-type beam position monitors in their apertures, the BPM will. August be on the downstream. ATF 2 end. FF of. Sextupoles the sextupole 26/27 th 2008 Msts 2

ATF 2 Magnets Name Requirements for the FF sextupoles: SD 4, SF 5, SF 6, from the V 4. 0 ATF 2 MAD deck K 2 L m-2 Pole at 30° (looking down beam) Integrated Gradient’ strength Aperture Diameter mm SF 6 8. 564562 North 37. 14 T/m 40 -50 SF 5 -0. 790868 South 3. 43 T/m 40 -50 SD 4 14. 909987 North 64. 655 T/m 40 -50 ∫G’. dl calculated for a 1. 3 Ge. V beam, using K 2 L= 2 Bpt. Leff/r 2(Bρ) and G’ = 2 Bpt/ r 2 26/27 th August 2008 ATF 2 FF Sextupoles Msts 3

ATF 2 Magnets 3 OLD SLAC sextupoles chosen to be used for FF sextupoles: all same style. Will meet requirements and have room for QBPM Style name= 1. 625 SX 3. 53 Bore diameter= 41. 28 mm Core length =89. 66 mm 26 turns of 0. 255” sq hollow Cu conductor per coil Used old magnets to save money 26/27 th August 2008 ATF 2 FF Sextupoles Msts 4

ATF 2 Magnets 1. 625 SX 3. 53 after refurbishment, on magnetic measuring stand at SLAC This is how some of the Synflex hoses will be placed: 2 inputs and 3 returns. 2 coils per water circuit. 26/27 th August 2008 ATF 2 FF Sextupoles Msts 5

ATF 2 Magnets FF sextupole on new support Here are the copper power terminals Here are some copper pipes that carry LCW & current from coil to coil New Al support 26/27 th August 2008 ATF 2 FF Sextupoles Msts 6

ATF 2 Magnets 26/27 th August 2008 Drawing of newly designed and made support. Will send copies of parts & assembly drawings to KEK. ATF 2 FF Sextupoles Msts 7

ATF 2 Magnets Side view of 2 FF sextupoles on their new supports Each sextupole has 4 tooling balls and they have been fiducialized on a CMM. Data will be sent to KEK. Are 3 thermal switches, at exits of the 3 water circuits. This is terminal block where their wiring goes 26/27 th August 2008 ATF 2 FF Sextupoles Msts 8

ATF 2 Magnets 26/27 th August 2008 Each magnet’s poletips were measured on a CMM. Only poles# 1&2 are removable ATF 2 FF Sextupoles Msts 9

ATF 2 Magnets “Non-terminal” end mechanical measurements from CMM. Tooling balls were fiducialized while on CMM. Fabrication tolerances. Aperture: 1. 625+/- 0. 001” Interpole gaps: 0. 3378 +/- 0. 002 “ 26/27 th August 2008 ATF 2 FF Sextupoles Msts 10

ATF 2 Magnet run at 35 amps for 3 hours, ∆P=118 psi. At KEK will be 80 psi. Coil temperature increased by ~ 0. 5ºC Magnets LCW at manifold (in & out) Magnet coil (purple) LCW supply at magnet ( Yellow) LCW return at magnet ( light blue) Ambient temperature 26/27 th August 2008 ATF 2 FF Sextupoles Msts 11

ATF 2 Magnets Integrated strength measured from 0. 4 to 50 amps: lower strength range than originally designed for. From this data on SN#1 can predict these 3 operating currents: SD 4 ~28. 5 amps SF 5 ~ 1. 4 amps SF 6 ~ 16 amps Each magnet has a 50 amp PS. Low current & low voltage of SF 5 will be dealt with by adding a ~0. 25 ohm air-cooled resistor in series with SF 5 26/27 th August 2008 ATF 2 FF Sextupoles Msts 12

ATF 2 Magnets Harmonics measured at the 3 nominal currents on SN#1. Quoted at 1 cm radius as percentage of sextupole. • Multipole harmonic tolerances quoted in table 3. 7 in section 3. 2 of the ATF 2 Proposal (August 2005). • 1 st allowed harmonic = 18 -pole – normal tolerance < 30. 6%; skew tolerance < 3. 74% • Measured 0. 018% at all 3 currents, all normal ☺ • Other harmonics’ tolerances and measurements at 1. 4, 16 and 27. 9 A – Octupole normal< 0. 66% ; skew<0. 21% – Measured 0. 11%; 0. 14%, 0. 14% ☺ – 10 -pole normal< 3. 53% ; skew< 0. 48% – Measured 0. 03%; 0. 008% ☺ – Are mixtures of normal and skew by the measured angles of their poles • Will measure harmonics on next 2 sextupoles & send values to Glen White for him to put in his model of FF to see if effects the spot size. 26/27 th August 2008 ATF 2 FF Sextupoles Msts 13

ATF 2 Actually the FF sextupoles will be aligned by a different method, not by changing their current. Magnets Magnetic center moved by about 1 micron during the complete sequence of BBA currents. Also true at 28 amps. 26/27 th August 2008 ATF 2 FF Sextupoles Msts 14

ATF 2 Magnets Present status and predicted shipping • 2 nd sextupole on the magnetic measuring stand. Waiting on Alignment Crew to align. • Expect to be measured by Friday 29 th Aug. • 3 rd sextupole will be measured next week • Crates are ready. Shipping ~ Sept 8 th • LCW hoses will be made next week. • Shipping paperwork starting ( 2 sextupoles are SLIGHTLY radioactive, just over the reporting limit). Will report details to Terunuma-san & arrange with him where to ship to 26/27 th August 2008 ATF 2 FF Sextupoles Msts 15