Extraction from the Delivery RingNovember 19, 2013

J. Morgan

Muon g-2

AP30

AP50

AP10

M1

Protonremoval

M3

Delivery Ring

AP0

M5

M2

M4

Conceptual Design

Antiprotonproduction

Muon Campus(g-2 operation)

Repurposing Pbar

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Muon g-2

AP30

AP50

AP10

M1

Protonremoval

M3

Delivery Ring

AP0

M5

M2

M4

Beamline Design – Dual modes

• 3.1 GeV/c Pion decay channel, beta functions need to be as small as possible to maximize muon capture

• 40 pi-mm-mr transverse acceptance, +/- 2% dp/p momentum acceptance

• Beam does a few turns in Delivery Ring to separate and eliminate protons

• Single turn extraction into M4 and M5• 8.89 GeV/c proton beam bypasses

Target Station and is transported in M3• Beam intensity is much higher that

Pbar was or g-2 will be• Protons are resonantly extracted from

the Delivery Ring• Extracted beam is transported down

M4 to the Mu2e Target

g-2 versus Mu2e operation

g-2 operation Mu2e operation

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Strategy for extraction plan- to provide maximum flexibility between experiments at least expense -

•Work around Mu2e extraction devices• Both single turn (g-2) and resonant (Mu2e) extraction • Resonant extraction more difficult to design for• Electrostatic septa on either side of D2Q3 during Mu2e operation• Lambertsons or Lambertson/bending magnet required on either side of D2Q5• Placement of extraction channel defined by resonantly extracted beam

•Try to reuse existing equipment• Pbar kickers have best combination of strength and aperture at FNAL• Kickers have the smallest physical apertures in the Delivery Ring• Need 8Qx at D2Q5, our donated ANL 8Q32’s need significant work• 8Q32 needs more rad. Hardened water lines, relocated power flags

•g-2 has acceptance goal of 40-pi-mm• Large displacement in both planes through D2Q5 limits aperture• Kickers must produce large separation (~48 mm) in Lambertson• Kicker(s) must produce 7 mr kick to achieve 48 mm separation

• New devices should be based on existing designs• Lambertson is similar to MLAW

• C-Magnet is shorter, larger aperture version of Main Injector ICA and has more turns• Try not to overlap injection and extraction regions

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Muon g-2

Conceptual Design

Extraction region

8Qx

circulating beam

upstream

downstream

8Q32 40 pi-mm-mr beam envelopes

Mu2e septa, relocated kicker

Delivery Ring extraction

•Extraction layout is driven by requirements for Mu2e resonantly extracted beam• Lambertson is required for Mu2e to work with electrostatic septa

• A larger aperture quadrupole is required at D2Q5, using ANL 8Q32• Mu2e resonantly extracted beam will be much smaller than g-2 muon beam• g-2 and Mu2e will use a Delivery Ring lattice similar to the Pbar Debuncher lattice• Different horizontal trajectories are needed for g-2 and Mu2e

• A large horizontal bump across the extraction region is used for g-2•g-2 needs an extraction kicker for beam to enter the M4 line

• Best location for kickers is where Mu2e septa will eventually reside• A two kicker system will be used for g-2 operation

• Can’t get 40 pi-mm-mr acceptance with 3 kicker system• Existing Pbar extraction kicker magnets can be reused

• Extraction scheme provides 40 pi-mm-mr acceptance for g-2 and a common extraction channel for both experiments

Pbar/Muon extraction Kicker

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g-2 operation and Mu2e commissioning

Horizontal bend (5)Injection kickers

Injection Pulsed Septumand C-magnet (septum)

Extraction Lambertsonand C-magnet (septum)

Extraction kickers

Vertical bends

Vertical bend

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Dual running mode configuration

Horizontal bend (5)Injection kickers

Extraction septa (Mu2e)

Extraction kicker (g-2)

Vertical bends

Vertical bend

Injection Pulsed Septumand C-magnet (septum)

Extraction Lambertsonand C-magnet (septum)

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Muon g-2

Conceptual Design

30 straight section – injection and extraction lines

M3

M4

M5

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Muon g-2

Mu2e Extraction Trajectory

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J. Morgan Muon g-2 Independent Design Review June 5-7 2013

Muon g-2

g-2 Extraction Trajectory

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J. Morgan Muon g-2 Independent Design Review June 5-7 2013

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Identical pair of Lambertsons won’t work, would need offset field region in LAM2

12Lambertson upstream, “C”-Magnet downstream

g-2 Extraction C-Magnet

downstream

upstream

Used 2004 beta functions,Upstream Bx 8.2 m, By 7.7 m (40 pi - 36.2 mm x 35.1 mm)Downstream Bx 14.0 m, By 4.5 m (40 pi - 47.3 mm x 26.8 mm)

40 pi-mm-mr acceptance beam envelopes

minimum separation required

Used 2004 beta functions,Upstream Bx 7.8 m, By 8.2 mDownstream Bx 13.8 m, By 4.1 m

g-2 Extraction Lambertson

downstream

upstream

40 pi-mm-mr acceptance beam envelopes

43.7 mm

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Candidate large aperture quadrupoles

Pbar LQx (6.5”) magnet Extended aperture along poles

ANL 8Qx (8”)magnetNo extended aperture

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Changes to improve acceptance in extraction region

•Extraction kicker moved as far downstream as possible• Potential conflict with Mu2e upstream electrostatic septa in dual-mode operation• Kicker must be modified to increase strength (8.33Ω instead of 10Ω) for dual-mode• 48 mm horizontal minimum separation required in Lambertson

•Large horizontal bump across extraction region• Takes advantage of available physical aperture of large quadrupole at D2Q5• Four motorized quadrupoles (existing in Debuncher) used to create bump• Either removed or greatly reduced for Mu2e

•Need 8 inch quadrupole at D2Q5• Pbar LQ magnet can almost work with current configuration• Our only 10Qx magnet isn’t strong enough and is too tall• The ANL 8Q32’s need to be refurbished

• C-magnet used in place of downstream Lambertson• Beams are thread through only one Lambertson instead of two• C-magnet aperture can be centered on extracted beam• Much less stray magnetic field in Delivery Ring• Allows lower trajectory through large quadrupole at D2Q5

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16

D2Q5 large quadrupole

17Quadrupole can be pitched to improve downstream aperture

•Aperture improves as ELAM and ECMAG move closer to the 8Q32• In general, apertures are driven by g-2 3.1 GeV/c

muon beam, strength by 8.89 GeV/c Mu2e beam• Lambertson has design bend angle of 38 mr, requiring

1.13 T-m of integrated field for the 8.89 GeV/c Mu2e beam

• “C”-Magnet has design bend angle of 57 mr, requiring 1.68 T-m of integrated field for the 8.89 GeV/c Mu2e beam

• Extraction devices under radiation shielding

Cartoon of extraction devices and approximate lengths

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Extraction magnets

Other magnet work in the near future and a problem

•B2 (GSJ) refurbishment, to replace the P-1 Line V714 C-Magnet• Schedule shows initial planning through December, planning finishing up in January and

work beginning at the end of February• Work scheduled to take 5.5 months

•CDA refurbishment, to replace the AP-1 F-17 C-Magnets• Schedule shows planning in January and February and work beginning at the end of February• Work scheduled to take 5 months

•May have aperture problem with M-5 horizontal bend magnets• Three horizontal bends of 154 mr each, 3.1 GeV/c beam• Original plan calls for MDC magnets which can comfortably provide ~1.6 T-m• Aperture a little tight after carefully considering the beam sagitta• Could “inner” turns of MDC be removed to open up aperture (56 vs. 68 turns)

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