DresdenDresden ElectronElectron BeamBeam IonIon SourcesSources:: LatestLatest DevelopmentsDevelopments

G.Zschornack, M.Kreller, A.Silze Dresden University of Technology V.P.Ovsyannikov, F.Grossmann, R.Heller, U.Kentsch, M.Schmidt, A.Schwan, F.Ullmann DREEBIT GmbH Dresden

DREEBIT GmbH Exciting Properties of Highly Charged Ions

Seite 2 Exciting Properties of Highly Charged Ions

Potential energy

The potential energy of an ion increases with the degree of ionization Example: Xe44+ has a potential energy that is 4600 times higher than that of Xe1+

High power deposition into the surface

The deposition of potential energy leads to ultrafast intense electronic excitations Power deposition: 1012 …1014 W/cm2

High yield of secondary particles

Irradiation with highly charged ions results in up to 300 times higher secondary particle yields

High specific energy gain for ion acceleration

linear accelerator: ~ q effective ion acceleration cyclical accelerator: ~ q2

Seite 3 Applications of Highly Charged Ions

The interest of using highly charged ions in both basic and applied research increases continuously

Basic Research Applied Technology

Seite 4 HowHowto produceproducehighly charged chargedions

Ion Accelerators ECR Ion Sources Electron Beam Ion Laser Ion Sources (GSI, TSR HD) Sources/Traps Ionization in high-dense Stripping Electron Cyclotron electron beams Pulsed laser irradiation of → up to bare nuclei at Resonance (ECR) selected targets high projectile energies heating of a electron beam magnetically confined compression in strong plasma magnetic fields

Ar16+, Ta38+, Au41+ up to small amounts of U92+

(© Uni Mainz) Pb27+ etc.

(© GSI Darmstadt)

92+ up to U Seite 5 EBITEBIT // EBISEBIS

Seite 6 EBITEBIT // EBISEBIS

Germany is the land with the highest EBIT/EBIS density!

Cryogenic EBIT/EBIS: MPIK Heidelberg TU Dresden MPIP Berlin DESY Hamburg GSI Darmstadt Warm EBIT/EBIS: TU Dresden FZ Dresden-Rossendorf FSU Jena University Duisburg-Essen GSI Darmstadt

Seite 7 EBIT Design

„„classical“classical“ roomroom-temperature-temperature EBIT cryogeniccryogenicEBIT EBIT

superconducting coils permanent magnets (SmCo, NdFeB) → (3… 8) T magnetic field (250…620) mT at the axis

2 2 ⇒ je > 1000 A/cm ⇒ je = (200… 600) A/cm

highest charge states bare ions up to Z=28, (52…54)+ (90…92)+ Xe , up to U Kr34+, Xe(44…48)+, Ir67+

large devices, compact, transportable, liquid helium cooling low initial and maintenance costs, latest developments: short setup times Refrigerator cooling

Seite 8 Dresden EBIT/EBIS: principle of operation

cathode drift tubes electronElektronen- extractor Kathode Driftr hren Extraktion collectorkollektor

UH electron beam

trap on U1 U3 trap off U2

Ee

UK UExtr

magnetic compression of the electron beam

Seite 9 Room-Temperature Sources of Highly Charged Ions

Dresden EBIT Dresden EBIS Dresden EBIS-A

• Low initial and maintenance costs • Low specific price per ion • Compact device, simple to operate • Long-term stable, reliable

• Photon spectroscopy inside the trap Seite 10 • Ion extraction with small beam emittance www.dreebit.com Room-Temperature Sources of Highly Charged Ions – Technical Parameters

parameter Dresden EBIT Dresden EBIS Dresden EBIS-A B / mT 250 400 600

max. Ee / keV 15 25 30

max. Ie / mA 50 100 200

-2 je / A cm < 300 < 300 < 600 L / cm 2 6 6 N333 magnet SmCo NdFeB NdFeB

Seite 11 ComparisonComparison ofof SizesSizes

LLNL EBIT trap region (photo MPI für Plasmaphysik Berlin) 4 m Dr. Biedermann HU Berlin

Dresden EBIT

Tokyo EBIT

Dr. F.Ullmann Dr. V.P.Ovsyannikov Seite 12 Ultimative Limits of Ion Production – Selection of Electron Energy

not available yet Dresden EBIS-A, EBIS-SC Dresden EBIS Dresden EBIT Even the Dresden EBIT is able to produce most of the possible ion charge states of all stable elements!

Seite 13 Ion Production at Optimal Electron-Impact Ionization Cross-Sections

not available yet Dresden EBIS-A, EBIS-SC Dresden EBIS Dresden EBIT The optimal ionization cross-section occurs at

2.7 x EB

Seite 14 Limits of Ion Production–IonizationFactor

electron energy limit for the Dresden EBIT/EBIS ion source family

Dresden EBIT Dresden EBIS

Dresden EBIS-A Dresden EBIS-SC

Seite 15 Upper Limit of the Electrical Trap Capacity

13 1/2 C = 1*10 * L[m] * Ie [A] * a * f / (Ee [eV]) elementary charges

L – trap length

Ie – electron beam current Ee – electron energy α - ratio of useable ions in the ion charge state distribution f - compensation of the electron beam

Ion source max. trap capacity role of α Dresden EBIT 3 x 108 e

Dresden EBIS 2 x 109 e

Dresden EBIS-A 4 x 109 e

Dresden EBIS-SC 6 x 1010 e Seite 16 Examples of Produced Ions

Seite 17 EBIS(W): An Innovative New Generation of Ion Sources

newnew + = productproduct

EBIS + Wien filter ÆÆ ion beams with individual ion charge states

Seite 18 „W“ – Family : A new Generation of Ion Sources

Dresden EBIT-W Dresden EBIS-W Dresden EBIS-AW

New product family: EBIS/T with integrated Einzel lense and Wien filter

Seite 19 „W“ – Family : Some Ion Extraction Spectra

Dresden EBIS Leaky mode

H2

Seite 20 „W“ – Family : Some Ion Extraction Spectra

Dresden EBIS leaky mode Xe-129

Seite 21 Comparison of Sizes – Dipole Magnet and Wien Filter

resolution > 80

Wien filter DREEBIT GmbH product number 21007 http://www.dreebit.com

Seite 22 Dresden EBIS-A: Beam Emittance

aperture

Seite 23 Dresden EBIS-A: Beam Emittance

Image created by the pepperpot system

Seite 24 RMS Emittance of a C6+ Ion Beam

RMS emittance of a 30 keV C6+ ion beam

Seite 25 The Next Generation: Dresden EBIS-SC

A new generation of EBIS sources, the Dresden EBIS-SC, is being designed for new fields of applications.

The Dresden EBIS-SC is a superconducting compact ion source which is based on the most modern principles of refrigeration technologies as well as electron-beam technologies.

Seite 26 The next generation: Dresden EBIS-SC

Parameter Value

Total length approx. 60 cm; DN350CF Magnetic field (on axis) up to 6 T Electron energy up to 30 keV Electron current 1 A → eff. electron current density > 1000 A/cm2 Trap length 20 cm, 8 drift tube segments individual controllable → Trap capacity up to 6·1010 elementary charges

Seite 27 The Dresden EBIS-SC Test Bench

view of the ion EBIS-SC extraction side without outer flanges

Electron gun gas insertion potential feedthroughsSeite 28 temperature sensors heating control Dr. F.Ullmann The Dresden EBIS-SC Test Bench

target electron gun chamber ion extraction with adjustable with integrated with FC 3 distance einzel lens cathode-anode

ion injection with LMIS

q/A analysis Dresden EBIS-SC FC 2 FC 1

DN350CF

quadrupole deflector 60 cm Seite 29 Dresden EBIS-SC: First (preliminary) Results

parameter value

electron beam current 750 mA

electron energy 10.5 keV

electron beam 0.9984 transmission ion pulse widths (6…10) μs

Seite 30 ApplicationsApplications inin AcceleratorAccelerator TechnologyTechnology

Seite 31 LowLow EnergyEnergy IonIon IrradiationIrradiation FacilityFacility

Seite 32 Applications: Low Energy Ion Irradiation Facility

ion deceleration down to 10 eV*q ion acceleration up to 1.5 MeV ion pulses from ns to 100 μs width DC ion beams beam diameters from 500 μm up to cm

Seite 33 ChargeCharge BreedingBreeding

Seite 34 Applications: Charge Breeding

Concept: Primary ion source → Beam of low charged ions → Injection into a charge breeding apparatus – ECRIS or EBIT → Reextraction of highly charged ions

Important properties of a charge breeder:

efficiency, rapidity, and properties of the extracted ion beam

Seite 35 Charge Breeding: Gold

500 EBIT + LMIS Injection x 5 EBIT Background 400 Au(43...53)+ Auq+ / Irq+ M 1/2 3/2 3/2 300 - 2p - 2p 3/2 5/2 3s - 2p 3d 3d

α Counts α 200 q+ q+

Cr K Au / Ir

Fe K RR β

100 α α n = 4 n = : n = 5 Cr K Cr Fe K Cu K 0 123456789101112131415 E (keV) x-ray

Seite 36 Charge Breeding: Liquid Metal Ion Source with Quadrupole Beam Bender

Au53+ Re-extraction from the EBIS LMIS New ion injection techniques for Bismuth Germanium Erbium Indium Gold quadrupole Ceasium beam 1+ Antimony bender Au Platinum Injection into the EBIS Praseodymium EBIS and others

Seite 37 ApplicationsApplications inin MedicalMedical TherapyTherapy AcceleratorsAccelerators

Seite 38 SynchrotronsSynchrotrons

Seite 39 Medical Cancer Therapy – Synchrotrons I

EBIS-SC

©HIT

Seite 40 ©HIT Medical Cancer Therapy – Synchrotrons II

Seite 41 Medical Cancer Therapy – Other Solutions ?

Seite 42 CYCLINACCYCLINAC

Seite 43 Medical Cancer Therapy – CYCLINAC I

TERA approach to treat moving organs and solve other problems: high-current cyclotron + novel fast-cycling linac = “CYCLINAC”

RF generators RF generation Fast cycling beam for tumour multi-painting

modules computer controlled of LIGHT source (synchro)cyclotron chopped beam at Seite 44 200-400 Hz

© U.Amaldi, A.Garonna Medical Cancer Therapy – CYCLINAC II

© U.Amaldi, A.Garonna Seite 45 Medical Cancer Therapy – CYCLINAC III

400 Hz Requirement: 1∗108 ions / puls

Seite 46 Summary http://www.dreebit.com

The Dresden EBIS/EBIT ion source family consists of four generations of ion sources: Dresden EBIT small-size room-temperature Dresden EBIS sources of highly charged ions Dresden EBIS-A high-performance Dresden EBIS-SC superconducting EBIS Broad fields of applications: • accelerator technology (medicine, surface science, AMS, …) • ion implantation • nanotechnology • surface analysis Seite 47 • ……. ThankThank youyou !!

Dr. Zschornack M.Kreller A.Silze http://www.tu-dresden.de

Dr. Ovsyannikov Dr. Grossmann R.Heller U.Kentsch

M.Schmidt A.Schwan Dr. Ullmann http://www.dreebit.com