This material is based upon work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661. Michigan State University designs and establishes FRIB as a DOE Office of Science National User Facility in support of the mission of the Office of Nuclear Physics.

Yan Zhang On behalf of the FRIB driver linac team

IPAC 2013, May 15, 2013, Shanghai

Design Integration of the FRIB Driver Linac

Introduction to NSCL and FRIB SRF and Cryomodule Cryogenic System Beam Diagnostics and MPS Online model Summary

Outline

Y. Zhang, IPAC2013, WEOBB102 , Slide 2

Introduction: National Superconducting Cyclotron Laboratory (NSCL) The Largest Campus-Based Nuclear Science Facility in USA

Y. Zhang, IPAC2013, WEOBB102 , Slide 3

NSCL

FRIB

Facility for Rare Isotope Beams (FRIB)

, Slide 4 Y. Zhang, IPAC2013, WEOBB102

The facility for rare isotope beams (FRIB) is a ten-year DOE US $700 million project for nuclear physics and nuclear astrophysics researches, to be built at the center campus of Michigan State University, East Lansing, USA

The FRIB driver linac consists of a Front End which includes ECR ion sources, LEBT, RFQ and MEBT, three linac segments, a charge stripper, two 180°folding areas and a beam delivery system to transport 400 kW heavy ion beams onto a fragmentation target for production of short-lived radioactive ion beams (RIB)

Linac Segment 1 Linac Segment 2 Linac Segment 3

Cavities QWR 80.5 MHz HWR 322 MHz

0.041 QWR 12 0.085 QWR 91 0.29 HWR 4

0.085 QWR 3 0.29 HWR 72 0.53 HWR 96

0.53 HWR 52

Cryomodules Acceleration 14 Rebunching 3

Acceleration 24 Rebunching 1

Acceleration 6 Rebunching 1

Parameters of uranium beam

EIN 0.5 MeV/u EOUT 16.6 MeV/u q +33/+34 352 eµA (10.5 pµA)

EIN 16.4 MeV/u EOUT 147.8 MeV/u q +76 to +80 655 eµA (8.4 pµA)

EIN 147.8 MeV/u EOUT 202 MeV/u q +76 to +80 655 eµA (8.4 pµA)

Y. Zhang, IPAC2013, WEOBB102 , Slide 5

Parameter List of the FRIB Driver Linac

• ECR ion sources are located at the ground level which are convenient to access • All the other linac segments are installed in a linac tunnel about 10 m underground • Total beam path of the driver linac is about 520 m • All ion beams can be accelerated to > 200 MeV/u and power on target 400 kW • Design of the tunnel shielding is based on 1 GeV proton, for future upgrade – ISOL • Spaces are also reserved for beam energy upgrade – above 400 MeV/u for all ions • Re-accelerator has been commissioned recently and successfully reaccelerate RIB

SRF and Cryomodules

Y. Zhang, IPAC2013, WEOBB102 , Slide 6

CAVITY QWR0.041 QWR0.085 HWR0.29 HWR 0.53

f MHz 80.5 322

Va MV 0.89 1.96 2.30 4.07

T K 2 (2.1)

Ep MV/m 35

Bp mT 70

Pd W 1.32 3.88 3.55 7.90

Pbeam W 313 690 1526 2701

PRF kW 0.7 2.5 3.0 5.0

Development of FRIB cavity

Multipacting of Cavity and RF Coupler

Y. Zhang, IPAC2013, WEOBB102 , Slide 7

Cavity on resonance case: magnetic coil is useless

Cavity detuned case: multipacting is suppressed

MP free new coupler design

CM Test Results

RF System

Y. Zhang, IPAC2013, WEOBB102 , Slide 8

ADRC Controller

Phase Fluctuations - PID vs ADRC

RF Reference Distribution

10.0625 MHz Reference Distribution line (capactive taps)

200W Termination

Load Cavity n LLRF Controller Cavity 2 LLRF

Controller Cavity 1 LLRF Controller

LPF 10.0625 MHz

(to PLL)

REF CLOCK MODULE 100W

10dBm

50dBm Insulated and Temperature Regulated

2 kW Amplifier 4 kW Output

LLRF

Cryomodule

, Slide 9 Y. Zhang, IPAC2013, WEOBB102

Vacuum Vessel

Resonator with Helium Vessel

Alignment Rail

Support Post

μ-Metal Shield

1100-O Aluminum 38 K Shield

2 K Helium Relief

Central Cryogenic Interface

WPM – Monitor Alignment of Cold Element

Y. Zhang, IPAC2013, WEOBB102 , Slide 10

TDCM

measured wire vibration frequency for the bench top set-up is 22.5 Hz

Cold BPMs

Y. Zhang, IPAC2013, WEOBB102 , Slide 11

• Transverse phase advance of a LS1 cryomodule is close to 180° • Beam based trajectory correction could solve the problem, but it is time consuming • Install cold BPMs and perform model-based corrections reduces beam tuning time

-0.006

-0.004

-0.002

0

0.002

0.004

0.006

0 3 6 9 12 15

Cen

troi

d (m

)

Z (m)

y - warmy - w + c

0.041 CM

BPM

QWR

SLND

Solenoid

Solenoid

BPM

BPM

Beam

Degauss with Solenoids and Correctors

Y. Zhang, IPAC2013, WEOBB102 , Slide 12

1

10

100

1000

10000

100000

-40.0 -20.0 0.0 20.0 40.0

B (G

)

z (cm)

Dipole

Solenoid U1 ~ 10 V

U2 ~ 200 mV

𝑀 = 𝐿𝐿𝑈𝑈𝑈𝐿

M = 0.3 ~ 0.6 Henry

Measurement of Mutual Inductance Measurement of Solenoid and Dipole Fields

t

I1

I2

1 ~ 2 Gs • Each solenoid is equipped with dipole correctors for both horizontal and vertical orbit corrections.

• Mutual inductance alone is not a concern. • Stray fields are comparable near cavity surfaces. • Degauss should be performed simultaneously.

Cryogenic System

Y. Zhang, IPAC2013, WEOBB102 , Slide 13

Heat Load (W) 2 K 4.5 K 38/55 K Cryomodules 2420 1440 6230 SC magnets 670 1000 Cryodistribution 950 5000 Total 2420 3060 12230

Cold Boxes Room

Warm Compressors Room Warm Gas Tanks

Beam Diagnostics and MPS

Y. Zhang, IPAC2013, WEOBB102 , Slide 14

Beam Diagnostics in Front End: 4 Slits 3 View Screens 8 Faraday Cups 2 Fast Faraday Cups 13 Profile Monitors 3 Beam Current Monitors 4 Beam Position Monitors 4 Emittance Monitors 2 Intensity Reducing Screens

-200

0

200

400

600

800

1000

1200

1400

-100 0 100 200 300 400

Degrees and KeV Cavity Phase Setting (degrees)

BPM1phase(degrees)BPMphase2(degrees)deltaE keV/nucleon

Prototype BPMs Tested

Halo Scraper Ring (HSR) – Beam Collimator and BLM at Low Energy

Y. Zhang, IPAC2013, WEOBB102 , Slide 15

238U Energy Loss Power Ion Chamber Signal Halo Ring Signal

Slow Loss at Halo Ring

10 MeV/u 0.7 W 0.07 pA* 10 nA

Fast Loss 1st β041 failure

0.5 MeV/u ~230 W/m 8×10-5 pA* 38 µA

Machine Protection System – MPS

Y. Zhang, IPAC2013, WEOBB102 , Slide 16

Fast response time needed: 35 µs • Detector 15 µs, MPS 10 µs and beam in pipe 10 µs

20

40

80

160

320

0 40 80 120 160 200

t (u

s)

Energy (MeV/u)

SS_yieldNb_melt

RF, BCM, BLM, HSR, Bending Magnets in Fast Protection System (FPS), other elements in Run Permit System (RPS)

100 MeV/u, 200 kW Uranium beam

Thermal shock damage by nominal uranium beam

Online Model – OpenXAL

Y. Zhang, IPAC2013, WEOBB102 , Slide 17

An online model

XAL Data Structure

Tuning Algorithm Optimizer

Online Model

Framework

Open source software tools from the successfully demonstrated XAL at SNS

An collaboration with multiple laboratories for OpenXAL is established • FRIB, SNS, ESS, CSNS, TRIUMG, GANIL

MySQL database interface added • Lattice into RDB, XAL configuration generated from RDB

FRIB specific devices added • Electrostatic element – quadrupole, bending, Einzel lens • Solenoid

Physics algorithm verification and design benchmark • Preliminarily benchmarked against IMPACT and COSY • Detail is going on, especially for x-y coupling

Preliminary services and application development • Architecture agreed • Initial application and services development are ongoing

OpenXAL Collaboration Satellite Meeting • Room 5G, 5/16 Thursday, 9 am to 12 pm

Thin Lens Model for Multi Charge State Beam

Y. Zhang, IPAC2013, WEOBB102 , Slide 18

U+33, U+34 U+33, U+34

U+76 U+77 U+78 U+79 U+80

Use thin lens model (TLM) tracking envelopes of different charge states

Re-combine all the envelopes Results agree with multi-particle

tracking simulations (IMP) Sufficient speed for online application

LS1, beam energy 0.5 to 17 MeV/u

Folding 1

LS1

Minimize Uncontrolled Beam Loss

Y. Zhang, IPAC2013, WEOBB102 , Slide 19

0.1W/m 1W/m Max dT 1.83K 8.93K

Halo Ring Beam pipe entrance

There are many technical challenges of the FRIB project. We only discussed a few of them and because of limited time, a lot of

challenges, even critical ones, cannot be all covered in this short talk. All the design and integration issues are properly addressed and in

very good progress. We have been benefited greatly from collaborations with multiple

institutes: ANL, BNL, CSNS, CU, FNAL, JLab, KEK, LBNL, LNL, SLAC, SNS, THU, TRIUMF, …, we will continue. We are on track to deliver the most powerful SRF linac for heavy ion

beams.

Summary

Y. Zhang, IPAC2013, WEOBB102 , Slide 20

Jie Wei, Yoshi Yamazaki, Winter Zheng, Zhengzheng Liu, Harry He, Felix Marti, Alberto Facco, Fabio Casagrande, Paul Chu, Peng Sheng, Dan Morris, Kent Holland, Eduard Pozdeyev, Nathan Bultman, Paul Gibson, Thomas Russo, Leitner Matthaeus, Kenji Saito, Bob Webber, Sheng Zhao, Yihua Wu, John Popielarski, Matthew Johnson, Oren Yair, Xing Rao, Ting Xu, Shelly Jones, Daniela Leitner, Michael Syphers, Xiaoyu Wu, Qiang Zhao, Ji Qiang, Richard Talman, Bob Laxdal, Yinong Rao, John Galambos, Sasha Aleksandrov, Tom Pelaia, Chris Allen, Mark Champion, Yoon Kang, Kim Sang-Ho, Zhenghai Li, Thomas Roser, Chris Gardner, Peter Thieberger, Peter Ostroumov, Richard Pardo, Hengjie Ma, Dana Arenius, Haipeng Wang, Rongli Geng, John Mammosser, and many others.

Acknowledgements

Y. Zhang, IPAC2013, WEOBB102 , Slide 21