NuMI

NBI03
Nov. 7-11, 2003
NuMI Primary Beam
S. Childress (FNAL)

NuMI PrimaryBeam
November 7, 2003

NuMI

NuMI Primary Beam
FNAL Site

NBI03
Nov. 7-11, 2003
NuMI Primary Beam
S. Childress (FNAL)

Beam enclosure entrances
thru Main Injector and
NuMI Target Service
Building (completed Oct)NuMI

NuMI Primary Design Parameters

NBI03
Nov. 7-11, 2003
NuMI Primary Beam
S. Childress (FNAL)

Proton beam energy

120 GeV

Spill cycle time>= 1.87 sec

Bunch length

3-8 nsec

Batch length

84 batches

Batch spacing

18.8 nsec (53 MHz)Transverse emittance

40π mm-mr expected (95%)
500 π mm-mr maximum envelope

Momentum spread2 x 10-4 δp/p 2σ expected
3 x 10-3 δp/p 2σ max

NuMI spill (pbar operation)
NuMI spill (no pbar operation)

5 batches = 8.14 µsec
6 batches = 9.78 µsec

Maximum intensity

4 x 1013 ppp (protons/spill)

Total beam power

404 kW at maximum intensity

NuMI

NuMI Primary Priorities: 2002-03

••
•
•
•
•
•

Finalize extraction & primary transport beam design
3-D modeling to understanding fitting in Main Injector – Recycler regionCompletion of magnet refurbishment & corrector fabrication
Kicker magnet construction
Completion of large magnet installation in tunnels accessed thru Main
Injector (Sept-Oct shutdown – our top priority)
Accelerator systems ‘NuMI mode’ beam tests (Bob Zwaska presentation)
Instrumentation design / construction« New BPM electronics« New SEM profile monitors (Sacha Kopp presentation)•NBI03
Nov. 7-11, 2003
NuMI Primary Beam
S. Childress (FNAL)

Understand beam sensitivity to error sources

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Beam Transport & ApertureClearance

Maxim al Beam Sizes, 500pi & 3E-3, vs Clearances

NBI03
Nov. 7-11, 2003
NuMI Primary Beam
S. Childress (FNAL)

09/27/02

100
Hor beta size

Horizontal plane80

Beam Size (mm)Hor eta size
60

Hor total size

40

Hor Bend Aperture
Hor Quad Aperture

20

Hor Trim Aperture

0-100-20

Hor Other Aperture
0100

200

300

400

Vert beta size
Vert eta size

-40

Vert total size
Vert Bend Aperture-60-80

Vertical plane

Vert Quad Aperture
Vert Trim Aperture-100

Vert Other Aperture
Station (m )NuMI

Main Injector Tunnel – MI60

NuMI

MainInjector

NBI03
Nov. 7-11, 2003
NuMI Primary BeamS. Childress (FNAL)

Recycler StorageRing

3-D model essential tobe compatible withother beams. Initiallymany uncertainties >
tolerances

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Extraction & Pretarget Enclosures

Extraction Enclosure
156 mrad down-bendPretarget Enclosure
98 mrad up-bend & target focus

NBI03
Nov. 7-11, 2003
NuMI Primary Beam
S. Childress (FNAL)NuMI

Kicker Construction

NBI03
Nov. 7-11, 2003
NuMI Primary Beam
S. Childress (FNAL)• 3 kicker Magnets« Each 2.2 m length« 60 kV max.
« 4.0 kG-m at nominal
48 kV• 2 magnets complete,3rd well advanced• Testing in progress

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NuMI Installation
MI-608 Region

NBI03
Nov. 7-11, 2003
NuMI Primary Beam
S. Childress (FNAL)

Extraction Lambertsons

Upstream NuMI Transport

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Installation NuMI Extraction Enclosure

NBI03
Nov. 7-11, 2003
NuMI Primary Beam
S. Childress (FNAL)

V108 down-bend dipoles

Quads before carrier
tunnel drift
Lined 70 m. carrier tunnel

NuMI

2003-2004 Shutdown Efforts

NBI03
Nov. 7-11, 2003
NuMI Primary Beam
S. Childress (FNAL)¾ For the upstream half of the NuMI primary beam: MI60 and Extraction Enclosures, the only work access isthrough the Main Injector / Recycler tunnel – with severe
restrictions on access options.
¾ All large magnets in these areas (except kickers) are now
installed¾ For 2004 shutdown (Summer) must install correctors, allinstrumentation, vacuum system, LCW hookup, remaining
cabling, and extensive testing.

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Preparing for Installation:
Pretarget Tunnel

NBI03
Nov. 7-11, 2003
NuMI Primary Beam
S. Childress (FNAL)

Tunnel still ‘a bit’ damp
Here primary installation isnot critical path. Access nottied to Main Injector
shutdown

Beneficial occupancy October ‘03

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Beta & Eta Functions:Primary Beam Design

NBI03
Nov. 7-11, 2003
NuMI Primary Beam
S. Childress (FNAL)NuMI

Targeting Requirements

beam rms 1 x 1 mmberyllium window support

Target Casing
0.4 mm wall
TargetCooling

Horn innerconductor
Baffle

21.4

15.0

6.4

waterline
supportringwaterloop
Beam 1,2,3 sigma

TargetØ6.

0NBI03
Nov. 7-11, 2003
NuMI Primary Beam
S. Childress (FNAL)• Beam’s eye view of targetand baffle.
• Beam size on target:(σ)
1mm• Position stability on target(σ) +/- 0.25 mm.
« Minimize physics
backgrounds

11.0

18.0

19.0
30.0

8.0
Scale4x,8.0

all units mm

Target Dim 7/01 Dwg Set

motion capability +/- 8 mm

• Angle stability on target 60µrad« Modest requirement for low
energy beam

NuMI

Instrumentation Design Impact:
Targeting Requirements

NBI03
Nov. 7-11, 2003
NuMI Primary Beam
S. Childress (FNAL)• Beam size at targeting leads to smaller profile monitor
SEM grid pitch (0.5 mm) at targeting [compared to 1mm along transport].
• To maintain position accuracy at target requires
functional instrumentation accuracy of a factor of 3-4
smaller than required beam control accuracy.
« Experience from many applications« Requirement for < 75 microns instrumentation accuracy• For targeting BPM’s use smaller diameter detector
plate separation (allowed by smaller beam) than alongtransport« Enhances detector accuracy proportionallyNuMI

Profile Monitor Usage

NBI03
Nov. 7-11, 2003
NuMI Primary Beam
S. Childress (FNAL)• Profile monitors have a dual use application in theNuMI primary line
« Determination of beam size and shape along thetransport and for targeting. This provides the primary
diagnostic for emittance or optics problems, as well as
fraction of beam targeted« Precision calibration for the BPM’s. This imposes
additional requirements for profile monitor position
reproducibility < BPM accuracy.

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NuMI Beam Position Monitors

NBI03
Nov. 7-11, 2003
NuMI Primary Beam
S. Childress (FNAL)

Target BPM’s

Transport BPM’s
Building new BPM electronics based on digital receiver technology.
Recently commissioned for Recycler Ring with excellentperformanceNuMI

NuMI Beam ControlNBI03
Nov. 7-11, 2003
NuMI Primary Beam
S. Childress (FNAL)• Beam position and profile monitor accuracy
requirements needed to respond to error source
sensitivity are well matched to those for targeting,within a factor of 2, with targeting being the more
severe.
• One disadvantage with NuMI beam control comparedto the Main Injector is the additive presence of error
sources from individual magnet string power supplies.
• NuMI beam control requirements for beam loss andtargeting control are met by the combination ofenhanced power supply stability <100 ppm for majorbends and always active position control [Developed for
TeV Switchard; used in several applications]NuMI

NuMI Primary Priorities: 2004

• Upstream enclosures beam ready by September 2004
• Fully beam ready by December 2004
• Major focus for:« Pretarget installation« Beam instrumentation construction« Main Injector full ring beam tests« Beam control implementation« EVERYTHING not yet done

NBI03
Nov. 7-11, 2003
NuMI Primary Beam
S. Childress (FNAL)