2/5/2003 Steve Werkema 1

ff Antiproton AcceptanceAntiproton Acceptance

Two Projects:Two Projects:

1. High Gradient Lithium Lens

2. AP2 Beamline and Debuncher Acceptance Improvements

2/5/2003 Steve Werkema 2

ff Antiproton AcceptanceAntiproton AcceptanceBasic Layout

Scope of Antiproton Acceptance projects:

Target station - downstream of target

AP2 beamline

Debuncher ring

2/5/2003 Steve Werkema 3

ff Antiproton AcceptanceAntiproton AcceptanceMotivation

Increase the number of antiprotons collected from the target by: increasing the gradient of the collection lens increasing the admittance of the AP2 beamline and the Debuncher

MARS model ofp phase space distribution at the center of the targetp/p < 2.25%, contains onlyp’s within acceptance of Li Lens

2/5/2003 Steve Werkema 4

ff Antiproton AcceptanceAntiproton AcceptanceHigh Gradient Lithium Lens - Parameters

3

Tar

get

Li L

ens

Pul

sed

Mag

net

29 cm 81cm

PresentPresent UpgradeUpgrade

Gradient 745 T/m 1000 T/m

Radius 1.0 cm 1.0 cm

Lifetime 9106 pulses 10106 pulses

2/5/2003 Steve Werkema 5

ff Antiproton AcceptanceAntiproton AcceptanceHigh Gradient Lithium Lens - Motivation

10% increase inp yield by raising the gradient from 745 T/m to 1000 T/mFactor of 2.3 increase inp yield by raising the gradient to 1000 T/m and doubling the AP2/Debuncher Admittance

Note: Thep yield improvement per gradient increase is greater at larger admittances

2/5/2003 Steve Werkema 6

ff Antiproton AcceptanceAntiproton AcceptanceHigh Gradient Lithium Lens – Present Performance

With the present design, the gradient would have to be lowered to 700 T/m to achieve a lifetime of 10,000,000 pulses.

Gradient (T/m)

Average Number of Pulses to Failure

1000 <500,000

900 1,000,000

800 3,000,000

745 9,000,000

700 >10,000,000

2/5/2003 Steve Werkema 7

ff Antiproton AcceptanceAntiproton AcceptanceHigh Gradient Lithium Lens – Goals & Action Plan

• GoalGoal: Operate a Lithium lens -- at a gradient of at least 1000 T/m for at least 10 million pulses

• ActionAction PlanPlan (in process for past 5 years): Liquid Li Lens development at BINP Improvement to present design

FEA model of present design Autopsies of failed lenses

New solid Li Lens design

2/5/2003 Steve Werkema 8

ff Antiproton AcceptanceAntiproton AcceptanceHigh Gradient Lithium Lens – Present Li Lens

2/5/2003 Steve Werkema 9

ff Antiproton AcceptanceAntiproton AcceptanceHigh Gradient Lithium Lens – Status

• Liquid Lithium Lens developmentProject terminated in FY 2002 without producing a viable lens prototype.

• Existing Lens improvements FEA: Peak stresses during lens operation are well

below the fatigue strength of the titanium septum failure initiated by another mechanism

Autopsies of five failed lenses:o 4 septum fractures, 1 water leak (control)o Preliminary analysis suggests that cracking had been initiated

prior to pulsing the lens ResultResult: Improved quality control during fabrication of

new lenses

2/5/2003 Steve Werkema 10

ff Antiproton AcceptanceAntiproton AcceptanceHigh Gradient Lithium Lens – New design

FeaturesFeatures: Diffusion bonded titanium body Thicker septum Li buffer volumes eliminated

Prototype #1 is under construction

2/5/2003 Steve Werkema 11

ff Antiproton AcceptanceAntiproton AcceptanceHigh Gradient Lithium Lens – Near Future

• Complete and test new lens design prototype #1

• Lens #22 autopsyLongest lived lens, did not fail during pulsing

• Refine and expand FEA model• Operate a lens constructed with improved quality

control procedures Operate for 1 month at 745 T/m then increase to 820 T/m

• Construct 2 new lenses with a thicker septum (20% – 50% thicker)

2/5/2003 Steve Werkema 12

ff Antiproton AcceptanceAntiproton AcceptanceAP2 & Debuncher Acceptance – Motivation

Goal: Goal: 40 mm-mrad transverse admittance

p phase space distribution exiting the lens for a gradient of 750 T/m.

p/p < 2.25%

Beamline optics have been adjusted to match Li lens aperture. Blue dots are horizontal, Red dots are vertical

(i.e. 2 points perp).

2/5/2003 Steve Werkema 13

ff Antiproton AcceptanceAntiproton AcceptanceAP2 & Debuncher Acceptance – Parameters

Recent Measurements

Physical Aperture

Goal

Horizontal (mm-mrad)

20 ± 1.5 40 40

Vertical ( mm-mrad) 12 ± 1.5 40 40

Momentum ±2.25% ±2.25% ±2.25%

2/5/2003 Steve Werkema 14

ff Antiproton AcceptanceAntiproton AcceptanceAP2 & Debuncher Acceptance – Issues

• Identification of limiting apertures• Correction of known limiting apertures

Beamline element alignment Orbit control

More AP2 trim dipoles Debuncher moveable quad stands

Element redesign

• Instrumentation issues– BPMs

2/5/2003 Steve Werkema 15

ff Antiproton AcceptanceAntiproton AcceptanceAP2 & Debuncher Acceptance – Status

The following projects are presently underway: AP2 and Debuncher documentation survey (TD)

Determine physical aperture everywhere in beamline from drawings and other documentation

AP2 line trim dipoles3 NDB dipole trims have been installed in the AP2 line during the past year

Install moveable stands on selected Debuncher quadsCables were pulled during the January 2003 shutdown. No new stands have been installed.

Beam studies88 Hours of beam studies in past year (next slide)

Debuncher BPM upgrade Have completed beam testing of a single BPM electronics prototype One sector of the Debuncher was instrumented during the January 2003 shutdown with upgraded BPM electronics

2/5/2003 Steve Werkema 16

ff Antiproton AcceptanceAntiproton AcceptanceAP2 & Debuncher Acceptance – Completed Studies

Beam studies completed within the past year Reverse proton studies

Re-commission and develop various beam manipulation procedures (Debuncher, AP2, DRF3, DRF1) (36 hr)

• Problem: have not yet been able to see beam on AP2 BPMs Debuncher BPMs (Re-commission old electronics and prototype testing of new

electronics) (8 hr) Aperture measurements (4 hr)

Stacking studies AP2 line orbit correction (12 hr) Measure AP2 + Debuncher admittance

(develop measurement techniques) (20 hr) Measure AP2 + Debuncher momentum aperture (8 hr)

2/5/2003 Steve Werkema 17

ff Antiproton AcceptanceAntiproton AcceptanceAP2 & Debuncher Acceptance – The Future

• Complete documentation survey• Complete Debuncher BPM upgrade• Install Debuncher moveable quad stands• Build prototype portable quad alignment device• Element redesign• Beam Studies

Commission new hardware Develop procedures (upgrade and test software & controls) Correct AP2 and Debuncher orbits

Note: much of the studies plan requires the new Debuncher BPMs and/or completed installation of the moveable quad stands.

2/5/2003 Steve Werkema 18

ff Antiproton AcceptanceAntiproton AcceptanceConclusion

Presentp yield:

1710-6 p/POT

Expectedp yield:

4010-6 p/POT

36 36 10101010pp/hr/hrdelivered to the Accumulator for stacking

For:51012 POT/pulse2.0 sec cycle time