PIPII Conceptual Design Paul Derwent for Valeri Lebedev

PIP-II Conceptual Design Paul Derwent (for Valeri Lebedev) PIP-II DOE Independent Project Review 12 -14 December 2017 In partnership with: India/DAE Italy/INFN UK/STFC France/CEA/Irfu, CNRS/IN 2 P 3

About Me: • Paul Derwent: – Role: Deputy Project Manager – Relevant Experience: • Associate Project Manager for Accelerator & Nu. MI Upgrades, NOv. A CD-4 2014 (2009 -2014) • Department Head: Recycler (2006 -2009), PIP-II (2014 -present) • Antiproton source: design, fabrication, installation, commissioning of Accumulator stacktail stochastic cooling system • Valeri Lebedev: – Role: Project Scientist – Relevant experience: • CEBAF commissioning • Tevatron Run II upgrades – Tevatron, Main Injector, Antiproton Source 2 12/12/2017 Paul Derwent | PIP-II Conceptual Design

Requirements • PIP-II performance goals and physics design flow down from the project Functional Requirements Specification • Approved by Chief Research Officer and Chief Accelerator Officer – TC: #ED 0001222 – Pip 2 -docdb 1166 3 12/12/2017 Paul Derwent | PIP-II Conceptual Design

PIP-II Performance Goals • Increase MI power from >1 MW (LBNF) in the energy range 60 – 120 Ge. V – To reduce the time for LBNF/DUNE to achieve world-first results • Increase Booster power from 80 to 160 k. W – 8 Ge. V program: SBNE, Muon program • To sustain high reliability operation of accelerator complex. • Future upgrades – Mu 2 e at 0. 8 Ge. V and ~100 k. W CW beam • White paper – ar. Xiv: 1307. 1168 v 2 [physics. ins-det] • Proposal to the Fermilab PAC expected in early 2018 – Beam power to LBNF to >2 MW – Provide a platform supporting a high duty factor/CW operation for future intensity frontier experiments getting beam simultaneously 4 12/12/2017 Paul Derwent | PIP-II Conceptual Design

PIP-II High Level Performance Parameters 5 12/12/2017 Paul Derwent | PIP-II Conceptual Design

PIP-II Components • 800 Me. V linac – Warm Front End – SRF section • Linac-to-Booster transfer line – 3 -way beam split to: (1) Beam dump, (2) Booster & (3) Mu 2 e-II • Upgraded Booster – 20 Hz, 800 Me. V injection • New injection area • Resonant Magnet Upgrade • Upgraded Recycler & MI – RF in both rings • Conventional Facilities – Includes 2 empty slots at the linac end (L≈23 m) – Up to 1 Ge. V • Cryogenic Plant 6 12/12/2017 Paul Derwent | PIP-II Conceptual Design

SC Linac - Main Part of PIP-II • SC Linac consists of – Room temperature front end (up to 2. 1 Me. V) – SC (cold) linac • 5 types of SC cavities: HWR, SSR 1, SSR 2, LB 650, HB 650 • 3 RF frequencies are used for acceleration b in the above figure: optimal for HWR, SSR 1, SSR 2; geometric for LB 650, HB 650 7 12/12/2017 Paul Derwent | PIP-II Conceptual Design

Warm Front End • • 8 15 m. A, 30 k. V ion source 2 m LEBT (chopper, dif. pumping, envelope match to RFQ) 2. 1 Me. V, 162. 5 MHz RFQ 14 m MEBT (bunch-by-bunch chopper, shielding wall, envelope match) 12/12/2017 Paul Derwent | PIP-II Conceptual Design

Accelerating Cavities and Cryomodules 9 12/12/2017 Paul Derwent | PIP-II Conceptual Design

Beam Dynamics in SC linac • Space charge effects are similar to SNS • Multi-particle simulations do not show beam loss – Focusing element strength supported by optics studies • Emittance exchange between and || degrees of freedom 10 12/12/2017 Paul Derwent | PIP-II Conceptual Design

Suppression of Microphonics and LFD • Lorentz Force Detuning is significantly increased in PIP-II: ~3 times compared to XFEL – Beyond present state of the art • Maximum detuning < 20 Hz (s<3 Hz) • Passive means – Minimize df/d. P – Minimize LFD – Minimize noise at 5 -to-2 K conversion • Active means – Adaptive LFD Control Algorithm initially developed with 1. 3 GHz CMs – Using a dressed SSR 1 cavity • s=7. 4 Hz 11 12/12/2017 Paul Derwent | PIP-II Conceptual Design

Requirements to Cryogenics • Requirements to cryo-plant are set by operation in CW – Operation in pulsed regime reduces cryo-load at 2 K from 2000 W to ~600 W • Cryo-plant power has operating margin – Change in Operating mode can provide margin for 2 K CW operation • RMS pressure fluctuations have to be <0. 1 mbar – Passive microphonics suppression 12 12/12/2017 Paul Derwent | PIP-II Conceptual Design Heat loads in the cry-distribution 70 K 5 K 2 K 680 W 140 W 250 W Projected parameters of cryo-plant Maximum cooling power [W] 70 K 5 K 2 K ≥ 9, 100 ≥ 1, 500 ≥ 2, 000

SC Linac-to-Booster Transfer Line • Major design features – – Bending radius is chosen to prevent Lorentz stripping up to 1 Ge. V Simple FODO optics, minimum number of power supplies 2 arcs, zero dispersion straight (between arcs) with beam switch Beam based energy stabilization with energy measured by 1 st arc BPMs • Or by Time-Of-Flight in the linac tunnel extension – Switching time from beam dump to Booster is determined by the voltage rate changes for SC cavities ≈20 ms still manageable voltage on the fast corrector – Crossing Tevatron tunnel • Tevatron tunnel is used for beam delivery to SY • Line to Booster is lifted to allow free passing through to SY 13 12/12/2017 Paul Derwent | PIP-II Conceptual Design

Booster Injection • H- strip injection occurs through vertical dogleg • Painting in X&Y planes – Vertical painting is done by changing dogleg dipoles • fast correctors in the beam line correct V. angle – Horizontal painting is done with Booster correctors – linac beam stays at the same point of the foil • Foil – 600 mg/cm 2 14 12/12/2017 Paul Derwent | PIP-II Conceptual Design Updated Design of the Booster Injection Girder

Slip Stacking in the Recycler • Slip Stack at 20 Hz and 50 % more beam – an increase of slip stacking efficiency: 95% 97% (total power loss unchanged) – Slip stacking cavities with higher voltage • Support Main Injector operations from 60 -120 Ge. V. – Slip stacking cavities should be able to work CW. • Cooling and voltage limitations in existing cavities 15 12/12/2017 Paul Derwent | PIP-II Conceptual Design

Acceleration in MI • More powerful RF system in MI – Present system can accelerate up to 6. 2 • 1013 – PIP-II requires 7. 5 • 1013 • Cavity can handle the voltage, amplifier needs more power – Have identified two possible upgrade options to existing cavities • Additional tube • Higher power tube 16 12/12/2017 Paul Derwent | PIP-II Conceptual Design

PIP-II Injector Test: PIP 2 IT • Mission Statement: The PIP-II Injector Test (PIP 2 IT) facility replicates the front end of the PIP-II linac through the first SSR 1 cryomodule. PIP 2 IT is intended to serve as a complete systems test that will reduce technical risks associated with the PIP-II linac in both pulsed and CW operating modes. It is anticipated that PIP 2 IT will be operated for several years beyond the initiation of PIP-II construction, with the eventual relocation of major PIP 2 IT components and systems into the PIP-II linac enclosure, where they will serve as part of the PIP-II front end. The construction and operating period of PIP 2 IT splits naturally into two phases. • Phase 1 – retirement of risks associated with operation of the PIP-II linac in pulsed mode as required for neutrino operations and described in the CDR (1% duty factor). • Phase 2 (not part of project) – retirement of risks associated with CW operations, in particular as related to utilization of the PIP-II linac for a second generation Mu 2 e experiment – important for future scientific opportunities with PIP-II linac – additional hardware : a high power beam dump 17 12/12/2017 Paul Derwent | PIP-II Conceptual Design

PIP 2 IT: 2015 30 ke. V LEBT 2. 1 Me. V RFQ 2016 MEBT 2018 10 Me. V 2017 HWR 2019 25 Me. V SSR 1 HEBT 40 m, ~25 Me. V Phase 1: retirement of risks associated with operation of the PIP-II linac in pulsed mode as required for neutrino operations and described in the CDR (1% duty factor). The primary risks to be retired during this period (now-2020) include: • Achievement of required beam characteristics from the ion source through the SSR 1 cryomodule – Operated 2 m. A, 20 Hz, 550 msec through MEBT ✓ • Demonstration of MEBT chopper operations at a level required for Booster injection – Operated 1 (of 2) prototype kickers with these parameters ✓ • • 18 Demonstration of the operation of the HWR cryomodule, with beam, in close proximity to the MEBT beam absorber Demonstration of stable beam acceleration in the SSR 1 cryomodule, under the full control of prototype RF control systems, including resonance control within the cavities 12/12/2017 Paul Derwent | PIP-II Conceptual Design

Summary • The PIP-II design concept is mature and will meet the specified technical performance requirements. – Areas of technical risk have been identified and provide engineering focus – The design concept is solid and has not changed significantly since June 2015 • The CDR was released this September – CDR has been independently reviewed by P 2 MAC (April 2017) • Since previous IPR (November 2016) considerable progress has been achieved in – Design of SRF cavities – Microphonics and LFD suppression – Understanding of beam dynamics in the rings • The conceptual design is sound appropriate for CD-1 Thank you for your attention 19 12/12/2017 Paul Derwent | PIP-II Conceptual Design

END 20 12/12/2017 Paul Derwent | PIP-II Conceptual Design

Beam Loss and Linac Activation • Intrabeam stripping is expected to be the major mechanism of beam loss – 0. 1 W/m corresponds to 15 mrem/hour @30 cm residual radiation for E>1 Ge. V 5 m. A RFQ current, 2 m. A in SC linac 21 12/12/2017 Paul Derwent | PIP-II Conceptual Design

Beam Emittance Growth due to Transition Crossing • Simulation have been benchmarked by measurements of beam acceleration in Booster • Simulation show that required longitudinal emittance (97% of particles in 0. 1 e. V∙s) can be achieved at PIP-II intensity – Trim quadrupoles are used for soft Q-jump – Sextupoles control second order slip-factor 22 12/12/2017 Paul Derwent | PIP-II Conceptual Design

PIP-II Injector Test (PIP 2 IT) • Scope: – A CW H- source delivering up to 15 m. A at 30 ke. V – A low energy beam transport (LEBT) with beam pre-chopping – A CW RFQ operating at 162. 5 MHz and delivering 5 m. A at 2. 1 Me. V – A medium energy beam transport (MEBT) with integrated wide band chopper and beam absorbers capable of generating arbitrary bunch patterns at 162. 5 MHz, and disposing of up to 5 m. A average beam current – Low b superconducting cryomodules (HWR, SSR 1) capable of accelerating 2 m. A of beam to 25 Me. V – Associated beam diagnostics – Beam Dump – Associated utilities and shielding 23 12/12/2017 Paul Derwent | PIP-II Conceptual Design