Perspectives in High Intensity Heavy Ion Sources for Future Heavy Ion Accelerators. L. Sun

Transcription

1 IMP Perspectives in High Intensity Heavy Ion Sources for Future Heavy Ion Accelerators L. Sun Institute of Modern Physics, CAS, , Lanzhou, China IPAC 18, April 29~May 4, 2018,Vancouver, CA

2 Preface JLEIC/Jlab (Proposal) FAIR/GSI (under construction) HIAF/IMP (Funded) RIBF/RIKEN (In operation) L. Sun, IPAC2018, Vancouver, 2/31

3 Preface QCD Nuclear Physics Intense heavy ion beams High beam power High Energy Density Physics High energy very heavy ion beams High power density Electron Ion Collider High energy ion beams High Luminosity L. Sun, IPAC2018, Vancouver, 3/31

4 Outline Accelerator Requirements High intensity HCI sources Future developments and perspectives L. Sun, IPAC2018, Vancouver, 4/31

5 Accelerator Requirements Facility Typical requirements of high intensity heavy ions Typical Ion Required Intensity* Pulse Length FAIR/GSI U μs HIAF/IMP U pμa CW Pulsed ms Physics Goal Nuclear Physics HEDP, ENC Nuclear Physics HEDP, ENC Status Construction Funded FRIB U 33+, pμa CW Nuclear Physics Construction RHIC Au ~40 μs Nuclear Physics Operation JLEIC Pb 30+ Pulsed ~ ms EIC Proposal * Particles per pulse L. Sun, IPAC2018, Vancouver, 5/31

6 Accelerator Requirements Requirements of ion source for those high energy (GeV/u) high current heavy ion accelerators Ion Source Q I Q E~Q 2 for cyclotrons E~Q for linac Higher power Simpler injection mode Developing intense highly charged ion source is both performance-effective and cost-effective. L. Sun, IPAC2018, Vancouver, 6/31

7 Accelerator Requirements 238 U U U 55+ Injection E(MeV/u) Output E(MeV/u) Design I max (ema) SC cavity HWR009+HWR015+ Spoke021 HWR009+HWR015+ Spoke021 HWR009+HWR015+ Spoke021 SC cavities = = =264 Solenoids CRM Reduced Total length(m) Budget reduced >70 M$ (MP not included) >100 M$ (MP not included) Courtesy of H. W. Zhao@ICIS 13 Talk L. Sun, IPAC2018, Vancouver, 7/31

8 Accelerator Requirements 238 U U U 55+ Injection E(MeV/u) Output E(MeV/u) Design I max (ema) SC cavity HWR009+HWR015+ Spoke021 HWR009+HWR015+ Spoke021 HWR009+HWR015+ Spoke021 It is very much worthy of developing highly charged ion source SC cavities = = =264 aiming at very high charge state!! Solenoids CRM Reduced Total length(m) Budget reduced >70 M$ (MP not included) >100 M$ (MP not included) Courtesy of H. W. Zhao@ICIS 13 Talk L. Sun, IPAC2018, Vancouver, 8/31

9 High intensity HCI sources A (n+1)+ ionization potential Atomic number It is hard to produce intense HCI beams HCI production needs energetic electrons T e HCI production cross sections is low» Long enough confinement time τ i» High enough electron density n e 6.8 ~ ~ ,474 ~ ,321 ~ ,000 ~ L. Sun, IPAC2018, Vancouver, 9/31

10 High intensity HCI sources EBIS or Electron Beam Ion Source» Invented by Dr. Donets in 1965» Control precisely and independently n e, T e and τ i, pulsed beam LIS or Laser Ion Source» Proposed by Dr. Bykovskii et al. and Peacock, Pease in 1969» Laser irradiation on solid target induced plasma, pulsed beam ECRIS or Electron Cyclotron Resonance Ion Source» proposed by Prof. Geller in late 1960s» Reasonable control of the n e, T e and τ i factors, dc and pulsed beam Charge Stripping Scheme» In operation for GSI since 1990s» HCI beams With high intensity low charge sate ion source + Linac + Stripper, pulsed beam L. Sun, IPAC2018, Vancouver, 10/31

11 High intensity HCI sources: EBIS Radial trapping of ions = space charge of the electron beam Axial trapping = electrostatic potentials at ends of trap Total charge of ions extracted per pulse: ~ ( ) x ( N e in the trap)-k 1 Ion output/pulse proportional to the trap length L, electron current I e, Ion q fraction K 2 Ion charge q increases with increasing confinement time Output current pulse almost independent of species or charge state L. Sun, IPAC2018, Vancouver, 11/31

12 High intensity HCI sources: EBIS RHIC-EBIS Source Assembly E-Gun (10 A) Superconducting Solenoid (5 T) Drift Tube Structure (P=10-10 Torr) Electron Collector Parameter RHIC EBIS Max. electron current I el = 10 A Electron energy E el = 20 kev Electron density in trap j el = 575 A/cm 2 Length of ion trap l trap = 1.5 m Ion trap capacity Q el = 1.1x10 12 Ion yield (charges) Q ion = 5.5x10 11 (10 A) Yield of ions Au 32+ N 32+ Au = 3.4x10 9 Courtesy of E. Beebe@ICIS 17 Talk L. Sun, IPAC2018, Vancouver, 12/31

13 High intensity HCI sources: EBIS RHIC-EBIS in Operation Total charge/pulse (10 11 ) Electron Beam Current (A) Courtesy of E. Beebe@ICIS 17 Talk L. Sun, IPAC2018, Vancouver, 13/31

14 High intensity HCI sources: ECRIS Plasma Magnet Microwave Electron Cyclotron Resonance Ion Source L. Sun, IPAC2018, Vancouver, 14/31

15 High intensity HCI sources: ECRIS ω rf GHz 24~28 P rf kw 10.0 B mirror T 3.7~4.0/2.2~2.8 B r T 1.8~2.0 SCECRIS@RIKEN Chamber ID mm Ø100~150 Mirror Length mm 400~500 HV kv 30 SuSI@MSU SECRAL, SECRAL-II@IMP L. Sun, IPAC2018, Vancouver, 15/31

16 High intensity HCI sources: ECRIS Xe ECRIS performances are keeping boosting in years ~ema order HCI beams available Ion beam I (ema) Frequency (GHz) O Ar Ar Ar Ar Ca Kr Kr Xe Xe Xe Xe Ta Bi Bi L. Sun, IPAC2018, Vancouver, 16/31

17 High intensity HCI sources: LIS Target Chamber P~10-6 Torr Target Laser pulse: ns Extraction Courtesy of S. Kondrashev/BNL L. Sun, IPAC2018, Vancouver, 17/31

18 High intensity HCI sources: LIS Target Chamber P~10-6 Torr Target Laser pulse: ns Extraction Courtesy of S. Kondrashev/BNL L. Sun, IPAC2018, Vancouver, 18/31

19 High intensity HCI sources: LIS Target Chamber P~10-6 Torr Target Laser pulse: ns Extraction Courtesy of S. Kondrashev/BNL L. Sun, IPAC2018, Vancouver, 19/31

20 High intensity HCI sources: LIS Target Chamber P~10-6 Torr Target Laser pulse: ns Extraction Courtesy of S. Kondrashev/BNL L. Sun, IPAC2018, Vancouver, 20/31

21 High intensity HCI sources: LIS Target Chamber P~10-6 Torr Target Laser pulse: ns Extraction Drift Length: L Pulse Length τ:2-30 μs τ L I L -3 Courtesy of S. Kondrashev/BNL L. Sun, IPAC2018, Vancouver, 21/31

22 High intensity HCI sources: LIS Target Chamber P~10-6 Torr Target Laser pulse: ns Extraction Drift Length: L Pulse Length τ:2-30 μs τ L I L -3 Advantage: Simple structure: Laser, Vacuum, Target, Extraction Short pulse:μs High charge state high intensity, tens of ema, ~10 11 ppp Ion beams of any solid materials Current (ma) Pulse width - Al 10+ Pulse width - Ta 1+ Current - Al 10+ Current - Ta From target to extraction point (cm) Al - 3 J/30 ns Nd-glass 1062 nm laser (10 11 W/cm 2 ) Ta - 1 J/5 ns Nd-YAG 532 nm laser (10 9 W/cm 2 ) Courtesy of S. Kondrashev/BNL L. Sun, IPAC2018, Vancouver, 22/31 5 Pulse length ( s)

23 High intensity HCI sources: LIS CSD of a lead ion beam generated by a CO 2 laser at a power density P~ W/cm 2 Max. 3.5 ema or ppp Pb 27+ with a pulse length of 3.6 μs 100 J/1 Hz MO-PA CO 2 -laser system CERN-ITEP-TRINITI collaboration on LIS Design study towards to LIS capable to meet LHC demand for Pb 25+ ions Courtesy of S. Kondrashev/BNL B. Sharkov and R. Scrivens, IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 33, NO. 6, P.1778, DECEMBER 2005 L. Sun, IPAC2018, Vancouver, 23/31

24 High intensity HCI sources: LIS Nd-YAG Laser 8 J/8 ns Nd-YAG Laser 8 J/8 ns Nd-YAG Laser 8 J/8 ns Nd-YAG Laser 8 J/8 ns LION source Ion Species Specs. Total Charge Peak Current C Ni Al Pulse length (FWHM) Avg C 46.5 ema 1.64 μs SD 3.5% 10% 6.7% Avg C 15.5 ema 2.24 μs SD 2.6% 5.9% 4.7% Avg C 35.2 ema 2.22 μs SD 2.6% 7.6% 8.1% Pulse to pulse stability: better than 10% Low Emittance: ~0.1 π. μm (n.rms) Routine operation (with):» LION source for RHIC in BNL» LIS source for NICA in JINR» LIS source for ITEP-TWAC Courtesy of H. Y. Zhao/IMP Courtesy of M. Okamura/BNL L. Sun, IPAC2018, Vancouver, 24/31

25 High intensity HCI sources: Charge Stripping RFQ, IH1, IH2 Alvarez DTL Single Gap Resonators Transfer to Synchrotron VARIS MUCIS f rf = 36 MHz HLI: (ECR,RFQ,IH) f rf = 108 MHz Alvarez DTL To SIS18 Foil Stripper PIG RFQ IH1 IH2 Gas Stripper 2.2 kev/u β = kev/u β = MeV/u β = m m U 4+ U MeV/u β= 0.16 Constructed in the 70 th, Upgraded in 1999, Injector for FAIR ion operation L. Sun, IPAC2018, Vancouver, 25/31

26 High intensity HCI sources: Charge Stripping VARIS Courtesy of Aleksey Talk R. Hollinger, M. Galonska, Nucl. Instr. and Meth. in Phys. Res. B 239, p.227 (2005) L. Sun, IPAC2018, Vancouver, 26/31

27 High intensity HCI sources: Charge Stripping 11.1 ema U 28+ Pulsed gas valve synchronized with beam pulse timing Gas back-pressure up to 12 MPa Charge distribution after stripping of U projectiles in a H 2 gas target for different target thickness in comparison with N 2 target 7.5 MPa gas cell 11.1 ema U MPa gas cell 11.5 ema U 29+ From formerly 7.6 ema (50% of FAIR requirement) 74% W. Barth, et al., /Phys. Rev. Accel. Beams, 20, (2017) P. Scharrer, at al., Nucl. Instr. and Meth. in Phys. Res. A 863, P.20 (2017) L. Sun, IPAC2018, Vancouver, 27/31

28 High intensity HCI sources: impact LIS EBIS L. Sun, IPAC2018, Vancouver, 28/31

29 High intensity HCI sources: impact LIS Single-turn injection:» RHIC» NICA EBIS, LIS EBIS Multi-turn injection:» FAIR» HIAF-pulse» JLEIC ECRIS, Charge Stripping CW operation:» FRIB» HIAF-CW» SPIRAL2 ECRIS L. Sun, IPAC2018, Vancouver, 29/31

30 Future developments and perspectives Next Generation ECRIS Tandem EBIS Gasdynamic ECRIS (G-ECRIS)+Stripping L. Sun, IPAC2018, Vancouver, 30/31

31 Next Generation ECRIS I q ω 2 ECR, G q ~(28/18) 2 = GHz~ G q =2.6 >1.0 ema U 34+, dc (>2.0 ema, pulsed) 2 nd G. ECRIS 3 rd G. ECRIS 4 th G. ECRIS Specs. Unit 45 GHz ECRIS L. Sun, IPAC2018, Vancouver, 31/31

32 Next Generation ECRIS 45 GHz (2017~2020) HCI currents with a 4 th G. ECRIS: A=12~ pua (dc) A=40~ pua (dc) A=100~ pua (dc), 50 pua (pulse) L. Sun, IPAC2018, Vancouver, 32/31

33 Next Generation ECRIS 45 GHz (2017~2020) HCI currents with a 4 th G. ECRIS: A=12~ pua (dc) A=40~ pua (dc) A=100~ pua (dc), 50 pua (pulse) L. Sun, IPAC2018, Vancouver, 33/31

34 Tandem EBIS Electron gun Superconducting solenoid-1 Superconducting solenoid-2 Electron collector Gun coil Transition region Collector coil Accelerating tube LEBT Courtesy of E. Talk L. Sun, IPAC2018, Vancouver, 34/31

35 Tandem EBIS RHIC-EBIS: Au 32+ ~ ions/pulse I e Increase from 10 A to 20 A (x~2.0) Regain optimal distribution K 1 K 2 (x~1.5) Tandem EBIS configuration (x~2.0) Extended EBIS superconducting solenoids@bnl Tandem EBIS Output Au 32+ ~ ions/pulse U 39+ > ions/pulse Courtesy of A.Zelenski@IPAC 18, TUYGBE4 Courtesy of E. Beebe@HCI Sources Symposium 2014 in Lanzhou L. Sun, IPAC2018, Vancouver, 35/31

36 G-ECRIS + Stripping Threshold of plasma density, cm-3 1.0E E E E E+012 Quasi-gasdynamic regime of confinement (isotropic VDF) N cr (100 GHz) Gasdynamic ECRIS Ncr (28 GHz) Geller Classical confinement Ncr (18 GHz) Classical ECRIS confinement (anisotropic VDF) 1.0E Electron temperature, ev Features High current density: 1~10 A/cm 2 Low emittance: ε rms <0.1 π.um High ionization efficiency Simple scaling of performance SMIS 37 Q highest Beam extraction Scaled performance at 100 GHz Current Density Carbon А/cm 2 Nitrogen А/cm 2 Oxygen А/cm 2 Argon А/cm 2 Xenon А/cm 2 Courtesy of Vadim Skalyga/IAP L. Sun, IPAC2018, Vancouver, 36/31

37 G-ECRIS + Stripping Intense metal beam production Pt SMIS37: <Z> Pt = GHz/100 kw SMIS75: <Z> Pt = GHz/200 kw Higher frequency: >100 GHz Better confinement: MHD stability ~20 ema U 1n+ Advantages Efficient acceleration before stripper Low beam emittance No life span in principle Produce both gaseous and metal beams Courtesy of Alexander Vodopyanov/IAP L. Sun, IPAC2018, Vancouver, 37/31

38 Next G. HCI sources: possibilities Tandem EBIS L. Sun, IPAC2018, Vancouver, 38/31

39 Next G. HCI sources: possibilities Tandem EBIS ECRIS Higher intensity linac ECRIS, Tandem EBIS, G-ECRIS+Stripping Flexibility in both single-turn or multi-turn injection for Synchrotron L. Sun, IPAC2018, Vancouver, 39/31

40 Conclusion Remarkable progresses in high intensity high charge state heavy ion sources development in recent years No all-purpose ion source available for exiting facilities and next generation heavy ion accelerators Next generation accelerators need more powerful HCI sources Next generation or future HCI sources provide more possibilities/flexibilities for next generation heavy ion facilities L. Sun, IPAC2018, Vancouver, 40/31

41 Thanks for your attention! HIAT 2018 Lanzhou, China Oct ,