Antiproton Production Plans

Antiproton Production PlansAntiproton Production Plans

Keith Gollwitzer

Antiproton Source DepartmentAccelerator Division

September 15, 2006

OutlineOutline•Brief Review of Antiproton Production

•Status

•Improvement Plan– Outlined in February– Status and Plans

120GeV Protons to Target120GeV Protons to TargetN

ickel Alloy T

arget with C

opper (air) cooling

Focus-Transport 8GeV SecondariesFocus-Transport 8GeV Secondaries

Pulsed Lithium Lens

Collect-Cool-Transfer-Stack&CoolCollect-Cool-Transfer-Stack&Cool

Debuncher

Accumulator

Accumulator Antiproton Energy Spectrum: StackingAccumulator Antiproton Energy Spectrum: Stacking

Injection

Depositio

n

Cor

e

StacktailPa

rtic

le D

en

sity

log

S

cale

Stacking ComparisonStacking Comparison

0

5

10

15

20

25

-10

0

-95

-90

-85

-80

-75

-70

-65

-60

-55

-50

-45

-40

-35

-30

-25

-20

-15

-10 -5 0

Days

Da

y's

Be

st

Ho

ur

of

Sta

ck

ing

(m

A/h

r)

0

500

1000

1500

2000

2500

To

tal

Pb

ars

(m

A/w

ee

k)

Mid-Nov to Shutdown -- openShutdown to Now -- filled

February’s “Future Pbar Work”February’s “Future Pbar Work”• Slip Stacking (7%)

– Currently at 7.5x1012 on average

– Design 8.0x1012 on average

• Lithium Lens (0 – 15%)– Lens Gradient from 760T/m

to 1000 T/m

• AP2 Line (5-30%)– Lens Steering– AP2 Steer to apertures– AP2 Lattice

• Debuncher Aperture (13%)– Currently 30-32 mm-mrad– Design to 35 mm-mrad

• DRF1 Voltage (5%)– Currently running on old

tubes at 4.0 MEV– Need to be at 5.3 MeV

• Accumulator and D/A Aperture (20%)– Currently at 2.4 sec– Design to 2.0 sec

• Stacktail Efficiency– Can improve core 4-8 GHz

bandwidth by a factor of 2

• Timeline Effects– SY120 eats 7% of the

timeline

Slip StackingSlip Stacking• Slip Stacking (7%)




to 1000 T/m



Booster took sometime to get back to providing the intense beam after the shutdown.

Main Injector is handling the beam quite well.

Only the last few weeks have been at 8x1012.

Quality is good – bunches could be a little shorter.

Lithium LensLithium Lens• Slip Stacking (7%)




to 1000 T/m



Problem has always been balance between lens production and lens lifetime as a function of gradient

New diffusion bonded lenses have been made. 8mm tested and used during the Fall 2005. Nominal 10mm improved design and has been tested and is being installed on target station module.

10mm lens will be the next one installed if the next lens failure does not occur in the next few weeks.

Will slowly increase gradient and have to make AP2 optics adjustment to match

Minimally expect longer lasting lens

AP2 OrbitAP2 Orbit• Slip Stacking (7%)


– Design 8.0x1012 on average• Lithium Lens (0 – 15%)

– Lens Gradient from 760T/m to 1000 T/m



During the shutdown, two additional trims were added to line.

To make progress requires long periods of stability of the 120GeV proton beam (Osc. Overthruster). BPM problems and needing to ask for “hours” while having pbar hungry customer.

Software progress has been great and awaits testing.

Low pass filter solution is near at hand

1/3 of filters installed; rest on order.

Will need to set program of many hours of watching the software run and make adjustments

1st Vertical BPM

Oth

er P

1 B

PM

s8th

H

7th H

5th

V

2nd V

http://www-bd.fnal.gov/cgi-mach/machlog.pl?nb=pbar06&action=view&page=-2683&button=yes&invert=yes

Debuncher ApertureDebuncher Aperture• Slip Stacking (7%)




to 1000 T/m



During the shutdown only the Extraction Kicker stand was motorized.

During startup admittances measured 33 mm-mrad.No work was done to optimize orbit/aperture with reverse protons.

Extraction kicker stand centered on stacking beam mid-June

Extraction Kicker beam tube was meant to be replaced during shutdown; vendor problem.

Hope for delivery by end of year

Installation is expected to be < 5daysLook for opportunity orSchedule orNext long shutdown

5% increase acceptance for large Δp/p antiprotons

DRF1DRF1The problem had been that the PA tubes were getting old and delivery had been delayed.

A full set of PAs arrived during the shutdown and now have 5.6MV.







timeline

Accumulator & D/A ApertureAccumulator & D/A ApertureV. Lebedev is looking at redesigning the Accumulator and D/A optics. The Acc optics were cobbled together 7 years ago. The D/A matches on paper.D/A BPMs is current project.







timeline

This will require lots of reverse proton study time.

First need to center beam in the quad centers with reverse protons and then optimizing the aperture.

Next implement optics change; probably several iterations.

Optimize stacking/cooling systems with new optics

Stacktail & Core SystemsStacktail & Core Systems4-8GHz core system had a coax cable replaced by fiber increasing the bandwidth as well as an attenuator removed to allow more gain.

Stacktail medium plate was replaced during the shutdown. Problem recently found and corrected.

There are many gain knobs and phases to setup the systems.





bandwidth by a factor of 2• Timeline Effects

– SY120 eats 7% of the timeline

Much work to be done here to find the best setup.

Measurements are/will be made to see how to get to the higher rates beyond the current system: bandwidth, notch filters, dynamic range, S/N….

TimelineTimelineWas not present for awhile.

Have been running 12hr/day and want primetime; successfully set SY run 0600-1800

Pbar people have been taking advantage after 1800 to tune

Now, SY goes off for 3 months.

Come back?? Running conditions???????

• DRF1 Voltage (5%)– Currently running on old tubes

at 4.0 MEV– Need to be at 5.3 MeV




• Timeline Effects– SY120 eats 7% of the timeline

Quick SummaryQuick Summary

• Antiproton beam is getting into the Accumulator– Stacktail will be continual tuning focus– Will be looking at Stacktail upgrade(s)

• Other aspects of antiproton production are being improved – Stable consistent production– More antiprotons delivered to Stacktail

Documents

Antiproton Production Plans