Memorandum – DRAFT (input please!)

April 27, 1999

To: MCC Operations, AD Distribution

From: Howard Smith, Mike Stanek

Topic: DRAFT – Reconfiguring Accelerator Systems for PEP/FFTB

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Beginning Wednesday May 5th we shall commence reconfiguration of the Accelerator Systems for the upcoming PEP run, as well as for an E157 run. This turn on shall present a series of complications above and beyond those seen previously. Complications include:

• Setup of injector for three (or four) drastically differing interlaced

electron pulse intensities (~1.5e10, ~2.5e10, ~4.5e10), (and later <2e9 for HER top-off)

• Setup of high current (4.0e10) short bunch (~1.0 mm?), low emittance (< 5.0 x 1.0 e-5 mR) E157 beam in the LINAC.

• Recommissioning of NDR RF cavity 590.

• Commissioning of the new e+ source target/capture/chicane girders.

...plus all of the "normal" surprises.

The goal shall be to have both e+/e- available for PEP injection as well as an E157 beam available in BSY as early as May 10th. We feel strongly that if we want to succeed at this goal, the initial setup emphasis should be placed upon the most difficult to establish beam, i.e. the E157 beam. We anticipate that this shall delay the availability of e+/e- to PEP compared to a setup absent of E157. In what follows (sort of a timeline, or "order of operations"), we adopt this strategy.

Prior to May 5th: (OPS, Area Managers)

• Search and secure NDR, SDR, e+ vault.

• BSY and PEP Injection BAS complete allowing beam to 30-5 (PEP), 52SL2 and D2 (E157). All relevant RSWCF matters resolved.

• Turn on all magnet and RF systems required in these areas (as compatible with E155x), with configuration values from startup configs referenced below.

• Complete cold and hot checks for each of these systems. Carefully document (CATER) problems which would interrupt ability to deliver beam to PEP/FFTB. Coordinate/prioritize repair activities with support groups (Power Conversion, Controls, etc.)

• Continuously monitor these systems to identify faults that would interrupt a PEP or FFTB program.

• PEP Injection/FFTB BGRP running (Stanek).

• Reconfigure injector for PEP operation using TGUN. Configs and Script per Turner (see detailed memo). Items requiring special consideration;

• Y extension steering.
• Sector 0 and 1 RF parameters.
• 178 MHz bunching with TGUN (@ 121kV?)
• Sector one normalized emittance < 20x20 e-5 meter radians.
• NLTR WS164 energy spread < 0.4 %
• Energy and steering feedbacks operational.
• Commissioning of "new" pulsed SBST0/SBST1 phase controls, as well as new BC 6 NLTR energy feedback.

• BC9 electrons only.
• Steer NLTR as necessary. Launch onto first NDR turn.
• Establish stored beam with extraction to NRTL.
• Steer stored orbit as necessary.
• Setup tune monitor diagnostics, set tunes to gold values.
• Tune throughput to > 90%.
• Complete any low current NDR RF setup required. (Akre)
• Steer NRTL compressor off to RTL stopper, reference orbit BC 8 scratch XXX.
• NRTL compressor on, 29 MeV (BC8), Amplitude feedback on.
• NREXT energy feedback (BC8) on..
• Establish BC8 to 2-9 dump.
• Measure sector two emittance BC8, tune NRTL eta and eta prime knobs as appropriate,

• Turn on BC11 electrons, tune throughput using pulsed controls. Iterate DC (i.e. steering) controls to establish >90% throughput for both e- beams. NREXT energy feedback (BC10) on.

• Turn on BC6 electrons, tune throughput as above using pulsed and DC controls to establish > 90% throughput for all three e- beams.

• Commission new BC6 NLTR energy feedback.

• Commission new BC3 NREXT energy feedback.

• NREXT steering and NRTL->S2 launch feedbacks on (BC3).

• Complete any required NDR RF setup issues for interlacing hi-lo current–e.g. cavity balancing
• Measure sector two emittance BC3, tune NRTL eta and eta prime knobs as appropriate

• Remove SLEDF ENLD fudges.

• In general, klystron compliments should be made the same on

• FFTB LINAC model consistent with Accelerator.

• Establish BC 10 (~4.0e10) to 52SL2/PR55.
• Phase klystrons as necessary.
• Steer LINAC orbit.
• Turn on LINAC steering loops on beam code 3. (LI03,LI06,LI12...)
• BSY energy feedback on.
• Tune sector 28 emittance using LINAC FBCK orbit bumps between
• sectors 12 and 18. Target S28 emittance < 5.0 x 1.0 e-5 mR.
• LEM working.

• Establish BC 8 (~1e10) to PEP HE extraction energy profile monitor 4076, minimize dE/E.

• Steer extraction/bypass as necessary to establish e- to ST 6049 at sector 30-5.

• Phase klystrons as necessary.

• Energy feedback on, gold orbit 60.

• Extraction to Bypass steering feedback (LI14) on, gold orbit 21.

• Sector 10 LINAC PLIC should be minimal (<10 mV) on BC 8.

• Start at 1 Hz, ~ 1.0e10... eventually target 2.0e10 electrons on toro 375.

• Confirm EP01 kicker hits beam using LINAC BPMs, Prof 171

• BC10 phase ramp should be about the same value as BC3.

• Optimize SXL steering onto target. Iteration with 400 and 500 girder steering as well as target steering/posphas may be required to achieve reasonable target yield.

• Tuneup POSPHAS and 20-4A drive for optimal dE/E and bunchlength at east turnaround "foils" monitor.

• Target yield (TMIT toro 529/ TMIT toro 376) > 3.0 with 25 GeV scavenger.

• Check steering East Turnaround to 4x6 to PRL launch.

• Establish >4e10 to PRL toro LI19 1152 with 2.0e10 scavenger on e+ target.

• 4x6 launch feedback operational, gold orbit #XXX.

• Steer PRL to WTA.

• WTA launch feedback operational, gold orbit #XXX.

• Establish > 3.0e10 to EP05 toro 3152 with 2.0e10 on e+ target.

• Launch e+ chicane inflector to SLTR, trombone, POSPHAS, 20-4A drive tuning.

• Establish SDR stored beam extracted to SRTL stopper.

• Steer SLTR as necessary, iterate positron tuning with stored beam envelope monitor.

• Steer SDR stored orbit as necessary.

• Setup tune diagnostics, set tunes to gold values.

• Target throughput (TMIT DR03 71 / TMIT DR01 1481) > 70%; 1.5e10 positrons to SRTL toro 71.

• Steer SRTL compressor off to BC6 reference orbit XXXX?.

• SRTL compressor on, 29 MeV ? , Amplitude feedback on.

• SREXT energy feedback on, gold orbit 139.

• SREXT steering feedback on, gold orbit 19.

• Establish BC6 e+ to 2-9 dump.

• SRTL steering feedback on, gold orbit 89.

• Measure sector two emittances, tune SRTL eta and eta prime knobs as appropriate.

• Establish BC6 (~1.0e10) to PEP LE EXT energy profile monitor 6450, minimize dE/E.

• Steer extraction/bypass as necessary to establish e+ to ST 9049 at sector 30-5.

• Sector 3 steering feedback (gold 111) operational for BC6 positrons as well as BC8 electrons.

• Energy feedback on, gold orbit #20.

• Extraction to Bypass steering feedback (LI08) on, gold orbit 18.

• Sector 4 LINAC PLIC should be minimal (<10 mV) on BC6.

• E+ emittance 4 x 0.3 e-5 m-rad at 2-9 before beam through SIT (per Iverson).
• Additional SIT tuning and spot size measurements per Iverson memo (2 shifts)

Database Models correct.