Antiproton Acceptance

1
Antiproton Acceptance

• Steve Werkema
• DOE Review
• February 24, 2004

2
Scope

• Two Projects
• AP2 Beamline and Debuncher Acceptance
  Improvements
• Project Leader Keith Gollwitzer
• High Gradient Lithium Lens Upgrades
• Project Leader Jim Morgan

3
Motivation

• Increase the number of antiprotons collected from
  the target by
• Increasing the admittance of the AP2 beamline
  and the Debuncher to 35 p mm-mrad
• Increasing the gradient of the collection lens
  to 100 kG/cm

Note Yield curves in model reduced by 10 to
approximately account for chromatic effects
4

• AP2 Debuncher Acceptance

• Overview of plan
• Status

5
AP2 Debuncher Acceptance -- Plan

• Identify Limiting Apertures
• Assemble Documentation and Drawings (FNAL Tech.
  Div.) (WBS 26.2.2.1)
• Optical Survey and Alignment (WBS 26.2.2.2)
• Chromatic correction of the AP2 beamline
  (LBNL) (WBS 26.2.2.7)
• Improve AP2 and Debuncher Lattice models (WBS
  26.2.2.8)
• Beam based determination of limiting apertures
  (WBS 26.2.2.9.2)
• Mitigate aperture restrictions
• Redesign/modify/rebuild/relocate beamline
  elements (WBS 26.2.2.5)
• Implement Beam Based Alignment
• Instrumentation upgrades (WBS 26.2.2.3)
• AP2 BPMs
• Debuncher BPMs
• Orbit control (WBS 26.2.2.6)
• Install additional dipole trims in AP2
• Motorized quad stands in the Debuncher
• Beam Based Alignment (WBS 26.2.2.4)
• Develop procedures
• Software development
• Beam studies (WBS 26.2.2.9)

6
AP2 Debuncher Acceptance Beam Based Alignment

• Beam Based Alignment
• Excite quad ? Measure Response ? Correct Orbit
• We will be able to accomplish this because
• Most quads have shunts installed
• Upgraded BPMs in the Debuncher and AP2
• Greatly increased orbit correction capability in
  the Debuncher and AP2

7
AP2 Debuncher Acceptance Chromatic Correction

• New Task added since July 2003
• Chromatic Correction of the AP2 Beamline
• Work being done by LBNL
• Model chromatic effects
• Beam studies to test model
• Propose correction scheme (August 2004)

AP2 line chromatic b-functions
8
AP2 Debuncher Acceptance Status (1)

• Identification of limiting Apertures
• Documentation and Drawings
• AP2 Physical Aperture table complete. Apertures
  have been incorporated into the AP2 lattice
  model.
• Debuncher Physical Aperture table was recently
  completed (still requires final error checking)
• Optical Survey
• Tunnel work is 90 complete (work includes
  network setup)
• Survey data are being compiled and analyzed
• Mitigate Aperture Restrictions
• Recent developments
• DRF3 move completed during the Fall 2003 shutdown
• Design work started for vertical band 4 cooling
  array upgrade
• Design work started for Debuncher extraction
  kicker beam pipe replacement

9
AP2 Debuncher Acceptance Status (2)

• Implement Beam Based Alignment
• Instrumentation
• AP2 BPMs
• Presently trying to understand and correct Deb.
  Extraction kicker noise Est. Completion SD 2004
• DAQ hardware software upgrade
• Est. completion Jan. 2005
• Debuncher BPM upgrade
• All 6 sectors installed and operational
• Console software is functional and in routine use
  some improvements are still being made.
• Orbit Control
• Debuncher motorized quad stands
• 10 stands installed during the Fall 2003 shutdown
• 96 new bumps have been calculated and tested
• Install an additional 20 stands during the Summer
  2004 shutdown

10
AP2 Debuncher Acceptance Bumps
New Debuncher BPM control system application ?

• Angle bump at the extraction kicker using a
  combination of trim dipoles and motorized quad
  stands.

11
AP2 Debuncher Acceptance Status (3)

• AP2 and Debuncher Lattice modeling
• Working OptiM models of the AP2 line and the
  Debuncher exist
• AP2 model has been updated with physical aperture
  information
• Debuncher and AP2 models will be updated with
  physical aperture and survey information as the
  data becomes available
• LBNL has developed a MAD model for the study of
  chromatic effects
• Beam Studies
• Recently completed studies (Sept. 2003 Feb.
  2004)
• Reverse proton studies
• Observation of beam signal on all AP2 BPM cables
• Commissioned the new Debuncher BPM electronics
• Commissioned bumps with new motorized quads
  (nearly complete)
• Development of beam based determination of
  Debuncher apertures
• Stacking studies
• Measure AP2 Debuncher admittance
• (development of measurement techniques)
• Development of AP2 BBA using Debuncher TBT
• p bumps in AP2

12
AP2 Debuncher Acceptance

• AP2 Debuncher admittances reported at the
  July 2003 review were
• Horizontal 20 p mm-mrad, Vertical 12 p
  mm-mrad

Debuncher admittances reported at the July 2003
review were Horizontal 25 p mm-mrad,
Vertical 20 p mm-mrad
13
AP2 Debuncher Acceptance Limiting Apertures
The numbers in this column were calculated
using b-functions at Dp/p 0
DRF3 was moved during the Fall 2003 shutdown
and is no longer an aperture restriction. Table
gives pre-move admittances.
14

• High Gradient Li Lens

15
High Gradient Li Lens Goals Plan

• Goal Operate a Lithium lens --
• at a gradient of at least 1000 T/m (34 ?)
• for at least 10 million pulses
• Action Plan
• New solid Li Lens design (began 2000) (WBS
  26.2.1.2)
• General Li Lens RD (WBS 26.2.1.3)
• Autopsies of failed lenses
• FEA model of present design
• RD of various Lens technologies
• Improve present Li Lens design (WBS 26.2.1.1)
• Fabricate New Lenses (WBS 26.2.1.5)

16
High Gradient Lithium Lens New Design

• Features
• Diffusion bonded titanium body
• Improved cooling
• Li buffer volumes eliminated

• Diffusion Bonding
• Better, more uniform cooling of lens body
• May allow use of new Ti alloy (Ti 10V-2Fe-3Al has
  a 15 40 better fatigue endurance limit)
• Simplified lens fabrication
• Elimination of weld joints on septum

17
High Gradient Li Lens -- Status

• New Lens design (diffusion bonded lens)
• Complete and test new lens design prototype 1
• Presently being pulsed on test stand at design
  gradient
• Over 1.5x106 pulses so far
• Intend to pulse to failure
• Construction on prototype 2 expected to begin in
  March 2004
• General Lens RD
• Lens autopsies complete
• Continue to refine and expand FEA model
• Ti 10-2-3 testing in process
• Modifications to existing lens design
• Presently operating a lens constructed with
  improved quality control procedures (Lens 28)
• In the pipeline
• Lens 29 (available in 2 weeks)
• Lens 30 (available in 10 weeks)

18
WBS Overview
19
Milestones
20
Major Shutdown Work

• Shutdown 2004
• Install additional 20 motorized quad stands
• Replace D4Q4
• DRF2 Move
• Shutdown 2005
• Wider Vertical Band 4 cooling arrays
• Upgraded Debuncher Injection Septum (SD 2004? )
• Motorized stands for Debuncher injection
  extraction kickers
• Possible modifications to Debuncher extraction
  kicker (SD 2004? )
• Possible implementation of AP2 chromatic
  correction
• Shutdown 2006
• New Debuncher extraction kicker (if not modified
  during SD 04/05)
• Implement of AP2 chromatic correction (if not
  implemented during SD 2005)

21
Conclusion The Bottom Line

• Presentp yield
• 16?10-6p/POT
• Expectedp yield
• (1.1)?(33?10-6p/POT)
• 36?10-6p/POT
• ? 52 ?1010p/hr
• Delivered to the Accumulator for stacking
• For
• 8?1012 POT/pulse
• (slip stacking)
• 2.0 sec cycle time

Note Yield curves in model reduced by 10 to
approximately account for chromatic effects