24th International Workshop on ECR Ion Sources (ECRIS'20)

28 Sept 2020, 08:30 → 30 Sept 2020, 16:56 America/Detroit

Guillaume Machicoane (FRIB)

ECRIS '20 Author Upload Guidance (002).pdf

ECRIS'20 First Announcement.pdf

ECRIS Program for Website.pdf

Monday Talks

• 10.20_I_Izotov_Gismo_Gasdynamic.pdf
• 11.15_D_Xie_Status_45_GHz.pdf
• 11.40_O_Tarvainen_Conceptual_Design.pdf
• 12.05_H_Ren_FRIB_28_GHz_ECR_Ion_Source_Dev.pdf
• 13.35_R_Racz_Imaging_x_Ray_Ranges.pdf
• 14.00_E_Naselli_High_Resolution_X_Ray.pdf
• 14.25_B_Isherwood_Relationship_Between_Diffusion.pdf
• 15.20_D_Pugachev_Poster.pdf
• 15.30_I_Isotov_Poster.pdf
• 15.40_F_Mamone_Poster.pdf
• 15.50_F_Lemagnen_Poster.pdf
• 16.00_O_Bajeat_Poster.pdf
• 16.10_B_Isherwood_Poster.pdf
• 9.05_L_Sun_FECR_Ion_Sources.pdf
• 9.30_C_Qian_LECRR5.pdf
• 9.55_L_Celona_AISHa_Ion_Source.pdf

Tuesday Talks

• 10.20_J_Li_Influences_of_Magnetic_Field.PPTX
• 11.15_D_Todd_Theoretical_Model.pdf
• 11.40_G_Castro_Experimental_Evidence.PPTX
• 12.05_T_Thullier_Simulation.PPTX
• 13.35_A_Pidatella_Progress.PPTX
• 14.00_J_Mendez_Guiding_Centre.PPTX
• 14.25_G_Mauro_Electromagnetic.pdf
• 15.20_S_Vala_Poster.PPTX
• 15.30_M_Marttinen_Poster.pdf
• 15.40_B_Bhaskar_Poster.PPTX
• 15.50_T_Andre_Poster.pdf
• 16.00_C_Wong_Poster.pdf
• 16.10_C_Wong_Poster.pdf
• 16.20_L_Henderson_Poster.pdf
• 9.05_W_Kubo_Plasma_Parameters.pdf
• 9.30_J_Guo_Solution_To-Plasma_Chamber.pptx
• 9.55_I_Wang_Development_of_HTO.PPTX

Wednesday Talks

• 10.05_W_Huang_Poster.pptx
• 10.15_L_Lei_Poster.PPTX
• 10.25_A_Bondarchenko_Poster.pptx
• 11.00_M_Muramatsu_Status_HIMAC_ECR.PPTX
• 11.25_S_Peng_Attempt_to_Develop.PPTX
• 13.20_L_Maunoury_Role_1_Plus.PPTX
• 13.45_J_Angot_LNL_GANIL.PDF
• 14.15_R_Scott_ECR3_Commissioning.pdf
• 14.25_J_Adegun_Improvement.pdf
• 14.35_B_Roeder_ECR_Plasma_Chamber.pdf
• 8.25_M_Won_Poster.pdf
• 8.35_I_Owada_Poster.PPT
• 8.45_T_Nagamoto_Poster.pdf
• 8.55_S_Harisaki_Poster.pdf
• 8.55_S_Harisaki_Poster.pdf.pptx
• 9.05_K_Sato_Poster.PPTX
• 9.15_L_Li_Poster.PPTX
• 9.45_Z_Shen_Poster.pptx
• 9.55_Z_Jia_Poster.PPTX

Monday 28 September

08:30 → 09:00 Opening Session

09:00 → 09:05 Status Report and New Development

09:05 → 09:30 FECR Ion Source Development and Challenges

FECR or the First 4th generation ECR ion source is
under development at Institute of Modern Physics
(IMP) since 2015. This ion source is aiming to extract
intense highly charged heavy ion beams in the order
of emA from the dense plasma heated with 45 GHz
microwave power. To provide effective magnetic
confinement to the 45 GHz ECR plasma, a state of
the art Nb3Sn magnet with min-B configuration is a
straightforward technical path. As there is no much
precedent references, it has to be designed,
prototyped at IMP through in-house development.
Meanwhile, other physics and technical challenges to
a 4th generation ECR ion source are also tackled at
IMP to find feasible solutions. This paper will give a
brief review of the critical issues in the development
of FECR ion source. A detailed report on the status of
FECR prototype magnet development will be
presented.

Speaker: Dr Liangting Sun (Institute of Modern Physics, CAS)

09:30 → 09:55 LECR5 Development and Status Report

LECR5 (Lanzhou Electron Cyclotron Resonance ion
source No. 5) is an 18 GHz room temperature ECR
ion source featuring Ø80 mm ID (Internal Diameter)
plasma chamber and high magnetic fields. It has
been successfully constructed at IMP recently and has
been fully commissioned to meet the requirements of
SESRI (Space Environment Simulation and Research
Infrastructure) project. According to the test results,
LECR5 can meet the requirements of SESRI with
sufficient beam intensities within the required the
transverse emittances. As LECR5 is designed to be
optimal for the operation at 18 GHz, we have
managed to explore the source performance at 18
GHz with a maximum microwave power around 2 kW.
Recent source test indicates, LECR5 can produce not
only high intensity ion beams such as 2.12 emA O6+,
121 e¿A of Ar14+, 73 e¿A of Kr23+, 145 e¿A of
Xe27+, but also very high charge state ion beams
such as 22 e¿A of Bi41+. This paper will present the
recent progress with LECR5, especially the intense
ion beam production and the beam quality
investigation.

Speaker: Cheng Qian (IMP/CAS, Lanzhou; University of Chinese Academy of Sciences, Beijing))

09:55 → 10:20 Status of the AISHa Ion Source at INFN-LNS

The AISHa ion source is an Electron Cyclotron
Resonance Ion Source designed to generate high
brightness multiply charged ion beams with high
reliability, easy operations and maintenance for
hadrontheraphy applications. The R&D performed by
the INFN-LNS team during the 2019/2020 has
allowed the improvement of the AISHa performances
up to 20% for some of the extracted beams: both
injection and extraction flanges has been improved
and a movable electrode has been installed. The low
energy beam transport has been equipped of an
Emittance Measurement Unit (EMU), working through
the beam wire scanners principle, for the
measurement of the vertical and horizontal emittance
of the beams of interest for hadrontherapy
applications. Beam emittance has been characterized
as a function of q/m and of the beam intensity to
highlight space charge effects. If necessary, the
beam wire scanners can be used for the
characterization of the beam shape. The perspectives
for further developments and plasma diagnostics will
be also highlighted.

Speaker: Luigi Celona (INFN-LNS)

10:20 → 10:45 Gismo Gasdynamic ECR Ion Source Status: Towards High-Intensity Ion Beams of Superior Quality

GISMO, a CW high-current quasi-gasdynamic ECR ion
source, is under development at the IAP RAS. The
quasi-gasdynamic confinement regime, featuring high
plasma density (up to 10^14 cm^-3) and moderate
electron temperature (~100 eV), allowed to extract
pulsed beams of H+ and D+ ions with current of 450
mA and RMS emittance <0.07 pi mm mrad*. It has
been already demonstrated that major benefits of
quasi-gasdynamic confinement, previously tested in
pulsed mode, are scalable to the CW operational
mode. In first experiments at GISMO facility, the ion
beams were extracted in pulsed mode from the CW
plasma of ECR discharge due to technical limitations
of cooling circuits. Proton beams with current up to
70 mA were achieved at extraction voltage of 40 kV.
A new unique extraction system especially effective
for the formation of high current density ion beams
was developed and tested. Latest results of beam
current, emittance and charge state distribution
measurements are presented. Another possible
application of a quasi-gasdynamic plasma might be
the intense source of vacuum ultraviolet radiation
(VUV). Results of VUV measurements performed at
GISMO facility are also presented.

Speaker: Ivan Izotov (IAP/RAS, Nizhny Novgorod)

10:45 → 11:10 Break

11:10 → 11:15 Status Report and New Development II

11:15 → 11:40 Status of the 45 GHz MARS-D Ion Source

Development of the MARS-D ECR ion source, a 45
GHz next generation ECRIS using a NbTi MARSmagnet,
has been continuously moving forward at
LBNL. Recent stress analyses and other key
components of the MARS-D ion source have been
essentially finalized. This article presents and
discusses the status of this new 45 GHz ECR ion
source, such as the latest design features and the
fabrication plan with funding available in the very
near future.

Speaker: Daniel Xie (LBNL, Berkeley, California)

11:40 → 12:05 Conceptual Design of Heavy Ion ToF-ERDA Facility Based on Permanent Magnet ECRIS and Variable Frequency RFQ Accelerator

Ion beam analysis is typically based on tandem
accelerators and negative ions. The required 5-20
MeV energies for heavy ion time-of-flight elastic
recoil detection analysis (ToF-ERDA) can be
achieved with a high charge state ion source and RFQ
accelerator. We present a conceptual design of a ToFERDA
facility based on a permanent magnet ECRIS
and variable frequency RFQ accelerating 1-10 pnA of
40Ar8+, 84Kr17+ and 129Xe24+ ions to 4-7, 10-15
and 13-20 MeV. We present the PM ECRIS
requirements focusing on the CUBE-ECRIS* with a
quadrupole min-B field topology. Beam dynamics
studies demonstrating good transmission of the
heavy ion beams from the ion source to the RFQ
entrance through the electrostatic low energy beam
transport (LEBT) and a permanent magnet dipole are
presented. The predicted LEBT transmissions of the
CUBE-ECRIS (rectangular extraction slit) and a
conventional ECRIS (circular extraction aperture) are
compared. The conceptual design of the RFQ is
described and the implications of the energy spread
on the high energy beam transport are discussed. It
is demonstrated that an energy spread below 0.2 %
is necessary for appropriate resolution of the heavy
ion ToF-ERDA.

Speaker: Olli Tarvainen (UKRI-STFC-RAL-ISIS)

12:05 → 12:30 FRIB 28 GHz ECR Ion Source Development and Status

To satisfy ultimate performance requirements for
heavy ions, a 28 GHz superconducting ECR ion source
is under development at the Facility for Rare Isotope
Beams (FRIB) in collaboration with Berkeley National
Laboratory. The construction and testing of the
superconducting magnet was completed at Berkeley
and delivered to FRIB in January 2018. The magnet
and cryostat have been assembled on the high
voltage platform. Magnet cooldown and field mapping
are planned by the end of 2020. The source
commissioning shall start in early 2021. Details of the
ion source design, current status of assembly, and
commissioning plan will be presented in this paper.

Speaker: Haitao Ren (FRIB, East Lansing, Michigan)

12:30 → 13:30 Break

13:30 → 13:35 Plasma Investigations

13:35 → 14:00 Imaging in X-ray Ranges to Locally Investigate the Effect of the Two- Close-Frequency Heating in ECRIS Plasmas

Plasma instabilities limit the ECR Ion Sources
performances in terms of flux of the extracted highly
charged ions by causing beam ripple and unstable
operation conditions. In a 14 GHz ECRIS (Atomki,
Debrecen), the effect on the plasma instabilities in an
Argon plasma at Two Close Frequencies heating
scheme (the frequency gap is smaller than 1 GHz)
has been explored. A special multi-diagnostic setup
[1, 2] has been designed and implemented consisting
of detectors for the simultaneous collection of plasma
radio-self-emission and of high spatial resolution
X-ray images in the 500 eV - 20 keV energy domain
(using an X-ray pin-hole camera setup). We present
the comparison of plasma structural changes as
observed from X-ray images in single and doublefrequency
operations. The latter has been particularly
correlated to the confinement and velocity
anisotropy, also by considering results coming from
numerical simulations.

Speaker: Richard Racz (Atomki, Debrecen)

14:00 → 14:25 High Resolution X-ray Imaging as a Powerful Diagnostics Tool to Investigate ECRIS Plasma Structure and Confinement Dynamics

High resolution spatially-resolved X-ray spectroscopy, by means of a X-ray pin-hole camera setup* ** operating in the 0.5-20 keV energy domain, is a very powerful method for ECRIS plasma structure evaluation. We present the setup installed at a 14 GHz ECRIS (ATOMKI, Debrecen), including a multi-layered collimator enabling measurements up to several hundreds of watts of RF pumping power and the achieved spatial and energy resolution (0.5 mm and 300 eV). Results coming by a new algorithm for analyzing Integrated (multi-events detection) and Photon-Counted images (single-event detection) to perform energy-resolved investigation will be described. The analysis permits to investigate High-Dynamic-Range (HDR) and spectrally resolved images, to study the effect of the axial and radial confinement (even separately), the plasma radius, the fluxes of deconfined electrons distinguishing fluorescence lines of the materials of the plasma chamber (Ti, Ta) from plasma (Ar) fluorescence lines. This method allows a detailed characterization of warm electrons, important for ionization, and to quantitatively estimate local plasma density and spectral temperature pixel-by-pixel.

Speaker: Eugenia Naselli (INFN/LNS, Catania University)

14:25 → 14:50 The Relationship Between the Diffusion of Hot Electrons, Plasma Stability, and ECR Ion Source Performance

Plasma instabilities complicate the operation of electron cyclotron resonance ion sources. In particular, quasi-periodic losses of electrons from confinement due to kinetic cyclotron instabilities hinder ion source performance. Empirical scaling laws help guide the development of sources away from the most unstable operating points but are poorly understood. Further advancement of ECR ion source technologies requires a deeper understanding of instabilities, scaling laws, and internal processes of the ion source plasma itself. We present here results of an experimental study into these instabilities and scaling laws, and measurements of hot electron diffusion (E > 10 keV) from the 18 GHz SUSI ECRIS at the NSCL. Measurements of the average argon current and the standard deviation of their variations across multiple unstable operating points are shown. These measurements are compared to measurements of electrons that diffuse axially from the plasma chamber. In doing so it will be shown how controlling the diffusion of electrons control the stability of the plasma and optimize the ion source's performance.

Speaker: Bryan Christopher Isherwood (MSU)

14:50 → 15:15 Break

15:15 → 15:20 Poster/ Short Presentation

15:20 → 15:30 Production of 48Ca and 48Ti Ion Beams at the DC-280 Cyclotron

The heaviest known elements (up to 118Og) were
synthesized at the U-400 cyclotron (FLNR JINR,
Dubna) by using a beam of 48Ca ions. During the
tests of the DC-280 cyclotron, intense beams of 48Ca
ions were produced. For the synthesis of the
elements 119 and heavier, intense and stable beams
of medium-mass elements are required, such as 50Ti
and 54Cr. Before starting the main experiments, we
test the production of 48Ti ion beam, which is less
expensive than 50Ti. The article describes the
method, technique, and experimental results on the
production of 48Ca and 48Ti ion beam at the DC-280
cyclotron from the DECRIS-PM ion source.

Speaker: Dmitry Pugachev

15:30 → 15:40 ECR Discharge in Solenoidal Magnetic Field as a Source of Dense Wide- Aperture Plasma Fluxes

Sources of dense plasma fluxes with wide aperture
are extensively used in applied science, i.e. surface
treatment, and as a part of neutral beam injectors.
ECR discharge in a solenoidal magnetic field (i.e. with
no magnetic mirrors for plasma confinement),
sustained by a powerful radiation of modern
gyrotrons is under consideration at IAP RAS as a
possible alternative to widely used vacuum arc, RF
and helicon discharges. The use of a high frequency
radiation (37.5 GHz) allows to obtain a discharge at
lower pressure, sustain almost fully ionized plasma
with density more than 10^13 cm^-3, whereas the
power on the level of several hundreds of kW allows
one to create such a plasma in considerably large
volume. In the present work fluxes of hydrogen
plasma with the equivalent current density of 750
mA/cm2 and the total current of 5 A were obtained. A
multi-aperture multi-electrode extraction system
design capable of forming the non-divergent ion
beam was developed with the use of IBSimu code.

Speaker: Ivan Izotov (IAP/RAS, Nizhny Novgorod)

15:40 → 15:50 Stable and Intense 48Ca Ion Beam Production With a Microwave Shielded Oven and an Optical Spectrometer as Diagnostic Tool

The CAPRICE ECRIS installed at the High Charge
Injector (HLI) of GSI produces highly charged ion
beams from gaseous and metallic elements. A high
demand of metal ions comes from the nuclear
physics, material re-search, and Super Heavy
Element group (SHE), and the most requested
element, besides 50Ti, is 48Ca. When this chemical
reactive material is deposited inside the plasma
chamber at internal components the stability can be
com-promised. Furthermore, it is difficult to find a
working point to guarantee a long-term stability as
the oven re-sponse time and the reaction of the
ECRIS are relatively slow. The monitoring by using an
Optical Emission Spectrometer (OES) facilitates
immediate reactions when-ever plasma instabilities
occur. For this reason, a real-time diagnostic system
based on an OES has been in-stalled at the ECRIS at
HLI for routine operation during the beam-time 2020.
The measured spectra revealed a parasitic oven
heating by coupled microwaves often com-promising
the ion source performance. Therefore, a tung-sten
grid has been installed to shield the oven orifice from
the coupled microwaves. The results in terms of 48Ca
beam intensity and stability are reported here.

Speaker: Fabio Maimone (GSI, Darmstadt)

15:50 → 16:00 New Metallic Stable Ion Beams for GANIL

GANIL has been producing many stable beams for
nearly 40 years. Constant progress has been made in
terms of intensity, stability and reliability. The
intensity for some stable metallic beams now exceeds
or approaches the pμA level at an energy up to 95
MeV/u: 1.14 pμA for 36S (65% enriched) at 77
MeV/u, 0.35 pμA for 58Ni (63%) at 74 MeV/u. The
presentation highlights recent results obtained for
28Si, 184W and 130Te using the GANIL s LCO (Large Capacity Oven) on the ECR4 ion source. To produce the tungsten beam, two injection methods were compared. For the first one, we evaporated some tungsten trioxide (WO3) with GANILs LCO.
For the second one, the injection in the plasma
chamber was made by using MIVOC (Metallic Ions
from VOlatile compounds) with a tungsten
hexacarbonyl (W(CO)6) compound. It was the first
time that we used metal carbonyl compounds and the
result is promising. All the tests have been qualified
to obtain the level of intensity and beam stability.
Theses good results led us to propose them for
Physics experiments.

Speaker: Frederic Lemagnen (GANIL, Caen)

16:00 → 16:10 A New Resistive High Temperature Oven for Metallic Beams Production

For the Super Separator Spectrometer (S3) [1]
currently under construction on Spiral 2 facility,
metallic beams of high intensities must be delivered
to impinge a target aiming to produce rare
radioactive isotopes for fundamental nuclear studies.
First requested beams are 58Ni, 48Ca, 50Cr, 50Ti or
50V with an intensity about 1,2.1013 pps. The
metallic ion beams will be produced by the Phoenix
V3 ECR ion source combined with a resistive oven
newly designed to cope with the beam specifications.
The evaporation of low vapor pressure metallic
elements (Ti, V...) requires temperature within a
range of 1900°C to 2000°C. A new design of a
resistive oven has been developed for this purpose.
The oven reached 2000°C in a test vacuum chamber
during 8 days. It has worked out in the Electron
Cyclotron Resonance Ion Source ECR4 at GANIL for
Titanium beam production. Further tests using this
ion source are under preparation for Ti and V beam
production. Flux and angular distribution of atoms
released by the oven are going to be measured offline
for optimizing crucibles geometries. Finally, the
oven will be integrated into the Phoenix V3 ECRIS for
Ti and V production.

Speaker: Olivier Bajeat (GANIL, Caen)

16:10 → 16:20 Microcontrollers as Gate and Delay Generators for Time Resolved Measurements

The diffusion of electrons from ECRIS plasmas results
in the emission of bremsstrahlung distributions from
the plasma chamber. ECRIS bremsstrahlung
measurements that are both time- and energyresolved
are often challenging to perform due to the
10's; 100's ms timescale that the plasma evolves
over. However, the advancement of low-cost
microcontrollers over the last decade makes timing
and gating photon spectrometers easier. We present
a proof of principle measurement which uses an
Arduino microcontroller as a gate-and-delay
generator for a High Purity Germanium (HPGe)
detector. An example plot of the time-resolved
bremsstrahlung spectrum, triggered by beam current
variation induced by kinetic instabilities, is shown.

Speaker: Bryan Christopher Isherwood (MSU)

16:20 → 17:00 Open Discussion

17:00 → 17:01 Adjourn

Tuesday 29 September

08:50 → 09:00 Announcements

09:00 → 09:05 Plasma Physics and Techniques

09:05 → 09:30 Plasma Parameters at Upper/down Stream Region Near Ecr Zone and Optimizing Microwave-Launching on ECRIS

We have investigated how to produce multicharged
ions efficiently. Recently, we have focused on waves
propagations in plasma and conducted the Upperhybrid
Resonance (UHR) experiments. [1] We have
also conducted experiments heating by the coaxial
semi-dipole antenna to enhance the right-hand
polarization wave, which contributes to ECR. [2]
Multicharged ion beams have been improved using
various means, e.g., the increase of the magnetic
field and the microwave frequency, the DC biased
plate-tuner, mixing low z gases, and the multiplex
frequencies heating. However, the microwave
launching position has been empirically determined
on conventional ECRIS's. There is still some room for
improvement with the respect to more efficient
excitation of the wave propagation. In this research,
we estimate the wave propagation near the ECR
zone, and in the opposite peripheral region beyond it.
We measure plasma parameters in those regions by
two Langmuir probes inserted into each location at
the same time. In near future, we optimize the
microwave-launching in the case of the fundamental
frequency for ECR and the second frequency for UHR
in order to enhance their incidence to the vacuum
chamber.

Speaker: Wataru Kubo (Osaka University, Osaka)

09:30 → 09:55 Tentative Solution to Plasma Chamber Cooling for High Power ECR Ion Source Operation

High charge state electron cyclotron resonance ion
source (ECRIS) is characterized by a so-called min-B
magnetic field configuration, which provokes the
localized plasma over-heating to plasma chamber
especially for the 3rd generation ECRISs at high
power operation condition. With the increase of rf
power, more plasma energy will be dumped to tiny
areas and result in a very high localized power
density, which is estimated to be up to 1 kW/cm2.
Few existing ECR plasma chamber cooling designs
can withstand such high heat fluxes. In this paper,
we report a new plasma chamber cooling design with
so-called Micro-channel cooling technology, which can
not only realize efficient heat transfer, but also
retains a small radial thickness that is beneficial for
the radial magnetic field. In order to evaluate the
performance of the cooling structure with microchannel
design, experimental cooling loop for high
heat flux has been designed and built at IMP. Initial
experiments demonstrate that optimized
configuration can achieve high heat flux cooling in the
range of 1 kW/cm2 and beyond. Based on these
results, a plasma chamber with micro-channel design
for SECRAL has been designed and tested.

Speaker: Junwei Guo (IMP/CAS, Lanzhou)

09:55 → 10:20 Development of HTO with Inductive Technology for Uranium Beam Production

A High-Temperature Oven (HTO) with inductive
heating technology has been developed successfully
in 2019 at Institute of Modern Physics. This oven
features durable operation temperature of >2000℃
inside the tantalum susceptor. By careful design the
oven structure, material compatibility and thermal
stress issues at high temperature has been
successfully handled, which enables the production of

400 eμA U33+ with SECRAL-II*. With necessary
refinement, this type of oven could also be available
with room temperature ECR ion sources, like LECR4
and LECR5. Some improvements in structure have
been proposed in this year. The design and testing
results will be presented in this contribution.

Speaker: Wang Lu (IMP/CAS, Lanzhou)

10:20 → 10:45 Influences of Magnetic Field Parameters to ECRIS Plasma Characteristics

To investigate the hot electron population and the appearance of kinetic instabilities in ECRIS plasma, the axially emitted bremsstrahlung spectra and microwave bursts emitted from ECRIS plasma were synchronously measured on SECRAL-II ion source with various magnetic field configurations. The experimental results show that when Bmin/Becr is less than ~0.8, the spectral temperature Ts increases linearly with the Bmin/Becr-ratio when the injection, extraction and radial mirror fields are kept constant. Above this threshold Ts saturates and the electron cyclotron instability appears simultaneously. This study has also demonstrated that Ts decreases linearly with the increase of the average gradient over the ECR surface when the on-axis gradient and hexapole field strengths are constant. In addition, it is found that Ts decreases with the increase of the gradient at the resonance zone at relatively low mirror ratio and is insensitive to the gradient at high mirror ratio when Bmin is constant. Compared to a recent study taken on a fully superconducting ECRIS, this study shows different results discussing the mechanisms behind the correlation of magnetic field parameters to Ts.

Speaker: Jibo Li (IMP/CAS)

10:45 → 11:10 Break

11:10 → 11:15 Plasma Physics and Techniques II

11:15 → 11:40 A Theoretical Model of High-Bmin Instabilities and Experimental Tests of Its Predictions

It is well known that ECR ion sources exhibit
instabilities when the source's minimum magnetic
field is approximately 80% of the resonant field or
greater, but the reasons for this instability have yet
to be satisfactorily explained. In this paper we
present a simple theoretical model that has the highminimum-
B instability as a consequence. We show
that this model predicts modes of operation with
high-minimum B that avoid that instability (including
multiple-frequency heating), and present results from
experimental tests of some of these predicted stable
modes.

Speaker: Damon Todd (LBNL, Berkeley, California)

11:40 → 12:05 Experimental Evidence of Trapped Waves in a Simple Mirror Magnetic-Trap

This work presents the first experimental
characterization of cavity modes trapped within a
plasma column in an axis-symmetric magnetic trap.
Trapped wave has been characterized by means of a
movable antenna as a function of the B_{min}/B_
{ECR} ratio and plasma parameters. The study
demonstrates that E.M waves can be trapped
between two R-cutoff layers, in proximity of the B
minimum position. Results suggest that the trapped
waves consist of Whistler waves, propagating
perpendicularly to the magnetic field and storing
large part of the E.M power introduced in the plasma
chamber. If R-cut-off is removed by increasing the
density, trapped waves are not detected anymore. A
typical Electron Energy Distribution Function
composed by two different electron populations is
measured in the layer where trapped waves are
revealed, suggesting that additional heating is
occurring. The existence of trapped waves in a
plasma column was already foreseen by several
studies concerning the development of kinetic
instability in plasmas and this experimental
characterization allows to shed more light on nonlinear
plasma coupling and to the generation of
supra-thermal electrons in ECRIS plasmas.

Speaker: Giuseppe Castro (INFN/LNS, Catania)

12:05 → 12:30 Simulation and Experimental Investigation of an Ion Source Metallic Oven

Oven are widely used to produce metallic ion beams
in ECRIS. A calcium oven dedicated to metal
evaporation up to 650°C has been investigated by
simulation and experience. The differential atom
emittance has been measured and is well reproduced
by the results of a Monte-Carlo simulation code. The
absolute atom flux was measured as a function of the
oven temperature and compared with theoretical
predictions. A quite good agreement is obtained with
theory and new values of Antoine's coefficient for
calcium are proposed. The simulation is used to
investigate the probability of on flight atom ionization
by the plasma as a function of the oven distance to
the ECR zone. With the PHOENIX V3 geometry, when
the oven is placed in the injection biased disk plane,
the ionization efficiency is 14%. This value in quite
good agreement with experiment. Theoretical
efficiency up to 57% is reachable when the oven
distance is reduced to 1 cm to the ECR zone.

Speaker: Thomas Thuillier (LPSC, Grenoble Cedex)

12:30 → 13:30 Break

13:30 → 13:35 Modelisation, Simulation

13:35 → 14:00 Progress in Self-Consistent Modeling of Time- and Space-Dependent Phenomena in Ecris Plasma

Resonant interaction with the microwave radiation in
ECRIS plasma leads to a strongly anisotropic electron
energy distribution function (EEDF), given as a
combination of two to three electron populations,
with the possibility to trigger kinetic instabilities. At
the INFN, further efforts have been paid to improve
and update self-consistent 3D numerical codes for
plasma electrons kinetics. Progresses have opened
several perspectives. It is now possible to derive
space-resolved EEDF, and compute space-dependent
energy and density maps. Also, the code has been
updated to provide reaction rates of electromagnetic
emissions, including X-ray fluorescence. An estimate
of the local ion charge state distribution is potentially
possible, and first evaluations are ongoing. Dealing
with fast-transient mechanisms, such as
electromagnetic emission via the electron-cyclotron
MASER instability, the code is now updated for locally
evaluating the EEDF anisotropy. We will present the
collected results, which we believe to have a relevant
impact both on the ECRIS plasma physics and on the
INFN's PANDORA project that plans to use ECR
plasmas for fundamental studies in Nuclear and
AstroNuclear Physics.

Speaker: Angelo Pidatella (INFN/LNS, Catania)

14:00 → 14:25 A Guiding Centre Approximation Approach for the Simulation of Electron Trajectories in ECR and Microwave Ion Sources

The Boris algorithm has become the standard for
particle trajectory integration in a magnetic field. The
high frequency electron cyclotron motion (GHz)
constrains the time-step below 10 ps. A guiding
centre approach neglects the detailed particle
cyclotron motion, describing its trajectory through
free motion of the orbit's centre along the field lines
and corresponding drifts. It works on the assumption
that the magnetic field strength varies in a much
larger length scale than the cyclotron orbit. This
approach is more computationally expensive per step
than direct orbit integration, but a shorter overall
computation time may be expected by using a larger
time-step (~100 ps). This work presents a study on
implementing the guiding centre approach in ECR ion
sources. It is shown to reproduce accurately the
trajectory drifts and confinement of electrons in a
minimum-B field, but the use of long time-steps
exacerbates a non-physical kinetic energy loss.
Following, non-confined electron trajectories in a
flatter field are analysed, as in a microwave discharge
ion source, where this method's drawbacks are
avoided due to a smaller magnetic field gradient and
a shorter electron lifetime.

Speaker: Jose Antonio Mendez (LPSC, Grenoble Cedex)

14:25 → 14:50 Electromagnetic Simulation of 'plasma-shaped' Plasma Chamber for Innovative ECRIS

The plasma chamber and injection system design
play a fundamental role in ECRISs with the aim to
obtain an optimized electromagnetic field
configuration able to generate and sustain a plasma
with a high energy content. In this work we present
the numerical study and the design of an
unconventionally-shaped cavity resonator* that
possesses some key advantages with respect to the
standard cylindrical cavities, usually adopted in ion
sources setups. The cavity geometry, whose design
has been completed on January 2020, has been
inspired by the typical star-shaped ECR plasma,
determined by the magnetic field structure. The
chamber has been designed by using the commercial
softwares CST and COMSOL, with the aim to
maximize the on-axis electric field. Moreover, a
radically innovative microwaves injection system,
consisting in side-coupled slotted waveguides, has
been implemented, allowing a better power coupling
and a more symmetric power distribution inside the
cavity with respect to the standard rectangular
waveguides. This new 'plasma-shaped oriented'
design could relevantly improve the performances of
the ECRISs while making more compact the overall
setup.

Speaker: Giorgio Sebastiano Mauro (INFI/LNS, Catania)

14:50 → 15:15 Break

15:15 → 15:20 Poster/ Short Presentation

15:20 → 15:30 Characterization of 2.45 GHz ECR Ion Source Bench for Accelerator-Based 14-MeV Neutron Generator

The 2.45 GHz Electron Cyclotron Resonance Ion
Source (ECRIS) has been indigenously developed.
This development of ECRIS aims to provide high
brightness, stable, and reliable D+ ion beam of 20
mA in continuous (CW) mode operation for
accelerator-based D-T neutron generator. The ECR
ion source setup consists of a microwave system, a
magnet system, a double wall water-cooled plasma
chamber, a high voltage platform, a three-electrode
ion extraction system, and a vacuum system. The
ECR ion source test setup is installed and deuterium
plasma generated. Three-electrode extraction system
is designed and fabricated for the ion beam
extraction. A ~10 mA deuterium ion beam is
extracted from the ECR ion source. The paper covers
the detailed experimental setup of ion beam
characterization and diagnostics used for
measurement of beam profile, beam current, and
beam emittance measurements. It also covers the
latest results of beam profile, and beam current
measurement as a function of extraction voltage, gas
flow, and acceleration voltage.

Speaker: Sudhirsinh J Vala (Institute for Plasma Research, Bhat, Gandhinagar)

15:30 → 15:40 Electron Cyclotron Resonance Ion Source Related Research and Development Work at the Department of Physics, University of Jyväskylä (JYFL)

Recent research work of the JYFL ion source team
covers multi-diagnostic studies of plasma instabilities,
high-resolution plasma optical emission spectroscopy,
ion current transient measurements to define the
total life-time of a particle in the highly charged
plasma. The JYFL team also elaborates the magnetic
and technical design of the unconventional ion source
named CUBE. The R&D work includes, in addition, the
commissioning and operation of the highperformance
18 GHz ECRIS, HIISI. The instability
measurements have revealed new information about
the parameters affecting the onset of the plasma
instabilities and shown that different instability modes
exist. The ion-beam transient studies have given
information about the cumulative life-time of highlycharged
ions convergent with the ion temperatures
deduced from the Doppler broadening of emission
lines. The CUBE prototype has a minimum-B
quadrupole magnetic field topology, similar to ARCECRIS,
and its all-permanent magnet structure has
been optimized for 10 GHz frequency. The CUBE
design will be presented along with its commissioning
status. The status and operational experience with
HIISI will be reported as well.

Speaker: Miha Marttinen (University of Jyväskylä, Department of Physics)

15:40 → 15:50 Study on the Correlation between Energy Distribution of Electrons Lost from the Confinement and Plasma Bremsstrahlung on a min-B ECR Plasmas

The study of plasma bremsstrahlung has been used as a diagnostic tool for understanding the behavior of confined plasma in Electron Cyclotron Resonance Ion Sources (ECRIS). In order to understand the relation connecting the confined plasma and the electrons escaping the confinement, a series of measurements have been made to measure the bremsstrahlung produced in the axial and radial direction along with the Lost Electron Energy Distribution (LEED) axially on JYFL 14 GHz ECR. We present here the effect of various source parameters on the axial and radial bremsstrahlung along with the LEED on a min-B confined ECR plasma. The measured LEED has been found to show a correlation with bremsstrahlung measurement and also have observed as a potential diagnostic method for instability. The explanation for observed LEED and bremsstrahlung trends is provided.

Speaker: Bichu Subhash Bhasi Bhaskar (LPSC, JYFL)

15:50 → 16:00 Ultra-High Current Density Produced by a 60 Ghz Ecr Ion Source

SEISM is a compact ECR ion source operating at 60
GHz developed up to 2014. The prototype uses a
magnetic cusp to confine the plasma. This simple
magnetic geometry was chosen to allow the use of
polyhelix coils (developed at the LNCMI, Grenoble) to
generate a strong magnetic confinement featuring a
closed ECR surface at 2.1 T. The plasma is sustained
by a 300 kW microwave pulse of 1 ms duration and
with a 2 Hz repetition rate. Previous experiments at
LNCMI have successfully demonstrated the
establishment of the nominal magnetic field and the
extraction of ion beams with a current density up to
~ 1A/cm2. The presence of "afterglow" peaks was
also observed, proving the existence of ion
confinement in a cusp ECR ion source. The last run
was prematurely stopped but the project restarted in
2018 and new experiments are planned in 2021. A
new transport beam line has been designed to
improve ion beam transport towards the beam
detectors. Short- and long-term research plans are
presented, including numerical simulations of the
beam transport line and future upgrades of the ion
source with the main goal to transform the high
current density measured into a real high intensity
ion beam.

Speaker: Thomas ANDRE (LPSC-CNRS)

16:00 → 16:10 Multi-Species Child-Langmuir Law with Application to ECR Ion Sources

We generalize the classical single-species Child-
Langmuir Law to analyze multi-species beams from
ECR ion sources. The formulation assumes the
relative weight of each species in the extracted beam
is known. We applied the results to charge state
distribution data from Artemis- and Venus-type
sources at the NSCL and LBNL respectively. The total
measured beam current is close to the maximum
current predicted by the multi-species Child Langmuir
Law in each case, which indicates that beam
extraction occurs around the regime of space charge
limited flow. Prospects for application of the results
and further studies on the topic are outlined.

Speaker: Chun Yan Jonathan Wong

16:10 → 16:20 Beams with Three-Fold Rotational Symmetry: A Theoretical Study

Beams from ECR ion sources have 3-fold transverse
rotational symmetry induced by the ECR sextupole.
The symmetry imposes equality constraints among
transverse beam moments, which can be derived
using a theoretical framework we developed. Since
the constraints are solely a consequence of the
rotational symmetry of external fields, they hold for
arbitrary charge state distribution and space charge
intensity. These constraints provide a new tool to
analyze phase space properties of ECR beams and
their impact on low-energy transport. We prove that,
regardless of their triangulation, beams with 3-fold
rotational symmetry have the same rms emittance
and Twiss parameters along any transverse direction.
These counter-intuitive results are applied to the
FRIB Front End to demonstrate how symmetry
arguments challenge long-standing assumptions and
bring clarity to the beam dynamics.

Speaker: Chun Yan Jonathan Wong

16:20 → 17:00 Open Discussion

17:00 → 17:01 Adjourn

Wednesday 30 September

08:10 → 08:20 Announcements

08:20 → 08:25 Poster/ Short Presentation

08:25 → 08:35 Improvement of the Cryostat System Performance of 28-Ghz Electron Cyclotron Resonance Ion Source of the Biba by a Radiation Shielding

The BIBA (Busan Ion Beam Accelerator) is a compact
linear accelerator facility using the 28 GHz ECRIS at
the KBSI (Korea Basic Science Institute). Our goal is
to generate high current fast neutrons using the
heavy ion interaction with a proton target. For a
stable operation of the superconducting magnets, the
performance of cryostat system is very essential at
the 28 GHz ECRIS. However, the emitted x-ray from
inner plasma chamber contributes to increase an
extra heat load to the cryostat system by absorbing
the cold mass of the superconducting magnet.
Therefore, we have measured X-ray spectra from the
28 GHz ECR ion source and tried to improve the
performance of the Cryostat System by a radiation
shielding. In this paper, we will present the test
results of X-ray emission on 28GHz KBSI ECRIS and
improved cooling system performance.

Speaker: Mi-Sook Won (Korea Basic Science Institute, Busan)

08:35 → 08:45 Precise Identification of Extracted Ion Beam Spectrum Initially Obtained in Synthesizing Iron-Endohedral Fullerenes on ECRIS

Electron cyclotron resonance ion source (ECRIS)
plasma has been constructed for producing
synthesized ion beams in Osaka Univ.[1,2] We hope
that it can become a universal source capable of
producing ions with wide range mass/charge ration
(m/q). We have been trying to produce endohedral
fullerenes in the ECRIS. We have conducted initial
experiments on production of them only in the
second stage of ECRIS. We have been using iron
vapor source by induction heating (IH) from the
mirror end along to the geometrical axis, and C60
crucible from the side wall, respectively. We
succeeded in realizing ECR plasma that fullerene and
iron ions coexist on the single stage ECRIS, even by
1kV extraction voltage.[3] By these experimental
series, the typical CSD suggests that there is
possibility of slight formation of iron fullerenes
compounds and iron endohedral fullerenes. We are
continuing to investigate the experimental conditions
that maximize spectrum corresponding to iron
endohedral fullerenes. In this paper we describe
preliminary experimental results of synthesizing ironendohedral
fullerene on the ECRIS.

Speaker: Issei Owada

08:45 → 08:55 High Intensity Vanadium-Ion Beam Production to Search for New Super- Heavy Element with Z = 119

We have begun searching for the new super-heavy
element (SHE) with Z=119 at RIKEN Heavy Ion
LINAC (RILAC). To overcome the small production
cross section of vanadium (V) beam on the curium
target, the project requires a very powerful V beam.
In order to optimize the beam intensity of V with the
charge state of 13+, we have investigated the effects
of the amount of V vapor, the power of 18- and 28-
GHz microwaves, and the strength of the mirror field.
While no significant effect was seen by changing the
mirror field Bext from 1.4 T to 1.6 T, the amount of V
vapor and the microwave power strongly affected.
Based on the correlation between the V-vapor and
the microwave power, we obtained a 600-euA V(13+)
beam with the V consumption rate of 24 mg/h and
the microwave power of 2.9 kW in order to execute
about 1-month SHE experiment. Furthermore,
because such strong mirror field enhances the
transverse beam emittance, it is important to control
the emittance with small reduction of the intensity.
We have successfully controlled the beam emittance
by using three pairs of slits (triplet slits) in LEBT by
eliminating the peripheral beam components in both
of the x-x' and y-y' phase spaces.

Speaker: Takashi Nagatomo (RIKEN Nishina Center, Wako)

08:55 → 09:05 Enhancing Production of Multicharged Ions by Pulse Modulated Microwaves under Low Z Gas Mixing Operation on ECRIS

We are aiming at producing various ion beams in ECRIS. In the case of producing multicharged ion beams, we try to enhance loss channel of low Z ions by means of adding pulse modulated microwaves to conventional gas mixing method.* Through these experiments, we explore the feasibility of selectively heating specific ions with pulse modulated microwaves and launching another low frequency RF waves. In gas mixing experiment, we use Helium as low Z gas for production of multicharged Ar and Xenon ion beams. These experiments are conducted by keeping the total pressure constant and changing the mixing ratio of Helium. The time scale of pulsed microwave is typically several to several hundreds of microseconds. We optimize the pulse period and duty ratio for producing multicharged ion beams. These effects are investigated to measure Charge State Distributions (CSDs). Also, we can measure the emittance using wire probe and multi slit attached to Ion Beam Irradiation System (IBIS). ** We estimate the normalized emittance from this measurement to determine index of ion temperature in the ECRIS. In this paper, we mainly describe the results of these active and additive methods at the ECRIS.

Speaker: Shuhei Harisaki (Osaka University)

09:05 → 09:15 Beam Profile Measurements of Decelerated Multicharged Xe Ions from ECRIS for Estimating Low Energy Damage on Satellites Components

Electron cyclotron resonance ion source (ECRIS) has
been constructed for producing synthesized ion
beams in Osaka Univ.,* Xe is used as fuel for ion
propulsion engines on artificial satellites. There are
problems of accumulated damages at irradiation and
sputtering by low energy Xe ion from the engine. It is
required to construct experimentally sputtering yield
databases of ion beams in the low energy region from
several hundred eV to 1keV, since there are not
enough data of satellite component materials.
Therefore, we are trying to investigate experimentally
sputtering yield on materials by irradiating the low
energy single species Xeq+ ion beams. However,
there is a problem that if the low extraction voltage,
the amount of beam currents is not enough to obtain
ion beam flux for precise evaluation of sputtering
yield data. Thus, we conduct to decelerate Xeq+ ion
beams required low energy region after extracting at
high voltage, e.g., 10kV. We measured the
decelerated beam profile with x and y direction wire
probes. As a result, we were able to estimate the
dose of ion fluxes. We are going to conduct
irradiation experiments on various materials.

Speaker: Koichi Sato (Osaka University, Osaka)

09:15 → 09:25 Observation of Cyclotron Instabilities in SECRAL-II Ion Source

Cyclotron instabilities in Electron Cyclotron Resonance Ion Source (ECRIS) plasmas are related to non-linear interaction between plasma waves and energetic electrons, resulting in strong microwave emission, a burst of energetic electrons escaping the plasma, and the periodic oscillations of the extracted beam currents. Precedent investigation of cyclotron instabilities has proved that Bmin/BECR can be treated as a magnetic field threshold. Recently, experiments with SECRAL-II ion source demonstrate that Bmin/BECR is not the only knob, and other field parameters have also been found to be related to cyclotron instabilities, such as mirror ratio and radial field. Namely, the trigger of cyclotron instability is a combination of many magnetic field parameters. This paper will give the experimental setup at IMP for cyclotron instability investigations and experimental observations will be presented.

Speaker: Lixuan Li (IMP/CAS)

09:25 → 09:45 Break

09:45 → 09:55 High Intensity Ion Beam Extraction System for FECR

To meet the beam requirements of High Intensity
heavy ion Accelerator Facility (HIAF), the Institute of
Modern Physics is developing a Fourth generation
ECR ion source (FECR). Targeting at the operation
frequency of 45 GHz, FECR is expected to produce
very high intensity highly charged heavy ion beams,
such as 1.0 emA 238U35+, 2 emA 78Kr19+, 10 emA
16O6+, etc. Based on the records with the 3rd
generation ECR ion source operating at 24~28 GHz,
the corresponding total drain current of FECR could
reach 20 ~ 60 emA. To extract such high intensity
multi-charged ion beams from the source with high
beam quality and transmission efficiency,
conventional diode or triode extraction system might
not be suitable, and therefore a 4-electrode
extraction system with a total extraction voltage of
50 kV is designed to mitigate the space charge
influences and minimize the beam emittance growth
in the extraction region. In this paper, a 3D model of
the FECR extraction system is built using the IBSimu
code. The electrode angles, voltages and electrode
spacings are optimized for different ion beam
conditions respectively. Beam properties comparison
of various simulation conditions are presented.

Speaker: Zhen Shen (IMP/CAS, Lanzhou)

09:55 → 10:05 39Ar Enrichment System Based on a 2.45 GHz ECR Ion Source

Aimed at improving the ATTA's (Atom Trap Trace
Analysis) dating efficiency with 39Ar radioactive
isotope, an isotope enrichment system has been
developed at IMP (Institute of Modern Physics) to
increase the abundance of 39Ar in the incident
sample gas. In this enrichment system, a 2.45 GHz
ECR ion source was designed to ionize sample gas
and produce isotopes beams with several mA, and
the isotopes beam is transported and separated in
the separation beam line, which is consisted of two
quadrupoles and an analysis magnet. The separated
isotopes are collected by a rotated aluminum foil
target. According to the recent cross-checked results
with ATTA, high enrichment factor of 39Ar isotope
has been successfully reached. This paper will give a
general introduction to the platform setup. The
isotope enrichment efficiency is the critical issue for
such a platform and will be specially discussed.

Speaker: Zehua Jia (IMP/CAS, Lanzhou)

10:05 → 10:15 Conceptual Design of an Electrostatic Trap for High Intensity Pulsed Beam

Highly charged ion sources play an important role in
the advancement of heavy ion accelerators
worldwide. The beam requirements of highly charged
heavy ions from new accelerators have driven the
performance of ion sources to their limits and
beyond. In parallel to developing new technologies to
enhance the performance of ECR ion source, this
paper presents a conceptual design of an ion trap
aiming to convert a cw ion beam into a short beam
pulse with high compression ratios. With an electron
gun, a solenoid and a set of drift tubes, the injected
ions will be trapped radially and axially. By
manipulating the potential of drift tubes, ions can be
accumulated with multiple injections and extracted at
a fast or slow scheme. This paper presents the
simulation and design results of this ion trap
prototype.

Speaker: Wei Huang (Institute of Modern Physics)

10:15 → 10:25 Numerical Simulations of Plasma Dynamics in ECRIS Afterglow

Plasma dynamics in the afterglow of ECRIS has been
studied through the Particle-in-cell (PIC) simulations.
A full 3D implicit electrostatic PIC code was
developed to meet the needs of ECRIS simulations
and to study the characteristics of the ECR plasma
during the afterglow. The initial plasma parameters at
the simulation start-up were assumed by referring to
the experimental diagnostics of the ECRISs from IMP,
Lanzhou. The dynamics of electrons and ions in the
presence of the external magnetic field and at the
absence of the microwave energy were simulated to
study the mechanism of afterglow. Through the
abundant diagnostics of the 3D PIC simulation, some
ECR plasma features during afterglow including the
plasma potential and electron energy distributions
could be obtained and analyzed. The goal was to
determine the important evolutions that contribute to
the afterglow and thus to have a clearer
understanding of ECRIS afterglow mode.

Speaker: Li Lei (University of Electronic Science and Technology of China, Chengdu)

10:25 → 10:35 Production of Metal Ion Beams From ECR Ion Sources

The work describes the preparation of metal ion
beams from ECR ion sources by the MIVOC (Metal
Ions from Volatile Compounds) method. The method
is based on the use of volatile metal compounds
having high vapor pressure at room temperature: for
example, Ni(C5H5)2, (CH3)5C5Ti(CH3)3 and several
others. Using this method, intense beams of
chromium, titanium, iron, and other ions were
obtained at the U-400 FLNR JINR and DC-60
cyclotrons (Astana branch of the INP, Alma-Ata,
Kazakhstan Republic).

Speaker: Andrey Bondarchenko (JINR)

10:35 → 10:55 Break

10:55 → 11:00 Applications

11:00 → 11:25 Present Status of HIMAC ECR Ion Sources

High-energy carbon-ion radiotherapy is being carried
out at Heavy Ion Medical Accelerator in Chiba
(HIMAC). Over 12000 cancer patients have been
treated with carbon beams having energies of
between 56-430 MeV/u since 1994. There are two
injectors in the HIMAC for medical and experimental
use. First injector consists of two ECR ion sources and
one PIG ion source, the RFQ linac and the DTL.
Usually, this injector suppling the carbon ion for
cancer therapy and various ion such as H, He, Fe, Xe
are accelerated for biological and physical
experiment. The 10 GHz NIRS-ECR ion source
produce the carbon ion for cancer therapy. The 18
GHz NIRS-HEC ion source produce He to Xe ions for
experimental use. Second injector consists of the
compact ECR ion source with all permanent magnet,
the RFQ linac and the APF IH-DTL. This injector
supplies the carbon ion for experimental use.
Additionally, we tried production of the Indium and
the Tin ions by using the In(C5H5) and the Sn
(i-C3H7)4 at the NIRS-HEC. Beam current of the
115In20+ and 120Sn18+ were 90 and 15 micro A,
respectively. Present status of ECR ion sources and
some development will be described.

Speaker: Masayuki Muramatsu (QST-NIRS, Chiba)

11:25 → 11:50 Attempt to Develop a 2.45 GHz Microwave Driven Source for Plasma Flood Gun

Plasma flood guns (PFGs) are widely used to
neutralize wafer charge during the doping process in
modern ion implanters. Compared with traditional dc
arc discharge with filament and RF discharge, the
microwave driven source that has long lifetime and
has no metallic contamination is regarded as a
potential choice of PFG [1]. Attempt to develop a
large scale PFG based on 2.45 GHz microwave driven
sources was launched at Peking University (PKU). A
prototype one is a miniaturized 2.45 GHz permanent
magnet electron cyclotron resonance (ECR) source to
produce point-like electron beam. In previous
experiments, more than 8 mA electron beam has
been extracted with a Φ6 mm extraction hole at an
input microwave power of 22 W with argon gas [2].
Recently, studies are focusing on the possibility of
producing of ribbon electron beams as PFG with
2.45GHz microwave driven surface wave plasma
(SWP) source. A cylindrical chamber surface wave
plasma generator with a using cylindrical dielectric
waveguide and a 70 mm×3 mm extraction slit was
fabricated. The primary test results were obtained.
More details of this PFGs will be discussed in this
work.

Speaker: Prof. Shixiang PENG (PKU, Beijing)

11:50 → 12:15 Open Discussion

12:15 → 13:15 Break

13:15 → 13:20 Charge Breeding

13:20 → 13:45 Role of the 1+ Beam Optics Upstream the SPIRAL1 Charge Breeder

The SPIRAL1 charge breeder (SP1CB) is under
operation. Radioactive ion beam (RIB) has already
been delivered [1] to Physicist for experiments.
Although charge breeding efficiencies demonstrated
high performances for stable ion beams, those
efficiencies regarding RIB are lower. The beam optics,
prior to the injection of the 1+ ions into the SP1CB, is
of prime importance [2] for getting such high
efficiencies. Moreover, the intensities of the
radioactive ion beams are so low, it is really difficult
to tune the SP1CB. A stable beam having a close B
is required to find out the set of optic parameters
preceding the tuning of the RIB. Hence, it has been
decided to focus our effort on that issue as to get
control of the 1+ beam optics leading to high charge
breeding efficiencies whatever the 1+ mass, energy
and Target Ion Source System used (TISS). Being
aware that TISS's provide ion beams with a specific
energy spread and knowing that the acceptance
energy of the SP1CB is rather narrow; that parameter
must play also a role in the charge breeding
efficiency. This contribution will show the strategy
undertaken to overcome that problem and the results
already obtained.

Speaker: Laurent Maunoury (GANIL)

13:45 → 14:10 LNL GANIL LPSC Collaboration On The Contaminants Reduction In ECR Charge Breeders

Contaminants reduction in Electron Cyclotron
Resonance Charge Breeders (ECRCB) is a key point
for the future experiments foreseen at LNL and
GANIL Isotope Separation On Line (ISOL) facilities.
According to the mass separator resolution set
downstream the ECRCB, the radioactive ion beam
study can be challenged in case of low production
rate. An ongoing collaboration between LNL, LSPC
and GANIL laboratories aims to improve the beam
purity, acting on all the pollutant causes.
Comparative experiments will be done at LPSC using
different techniques, like covering the plasma
chamber wall with liners in several material. Different
configurations of the ECRCB will also be tested, with
the enhancement of the efficiency and charge
breeding time parameters as additional objectives. A
presentation of this program is proposed together
with the effective upgrade of the LPSC 1+N+ test
bench which goal was to improve the vacuum quality
and clean all the beam line devices.

Speaker: Julien ANGOT (Université Grenoble Alpes, CNRS, Grenoble INP, LPSC-IN2P3, 38000 Grenoble, France)

14:10 → 14:15 Poster/ Short Presentation

14:15 → 14:25 ECR3 Commissioning and Planning for C-14 Ion Beams at the Argonne Tandem Linac Accelerator System

The Electron Cyclotron Resonance Ion Source ECR3*
has recently been commissioned at the Argonne
Tandem Linac Accelerator System (ATLAS) at
Argonne National Laboratory. While ECR3 can provide
many of the stable ATLAS beams, its other intended
purpose is the production of C-14 ion beams which
were previously produced by a now-retired negative
ion source. This paper will discuss the final
installation and commissioning of the ion source as
well as the preparations for running C-14. A stable
C-13 ethylene gas was used as a surrogate to
determine the expected level of N-14 contamination
when running C-14 since they are inseparable at
ATLAS. We were also able to confirm consumption
rates and charge state efficiencies under different
C-13 running conditions in order to optimize the
upcoming C-14 beam production.

Speaker: Robert Scott (Argonne National Laboratory)

14:25 → 14:35 Improvement of the Efficiency of the Triumf Charge State Booster

The Electron Cyclotron Resonance Ion Source is a
versatile and reliable source to charge-breed rare
isotopes in TRIUMF's Isotopes Separation and
Acceleration (ISAC) facility. Significant research work
has been done by different groups worldwide to
improve the efficiency and performance of the ECRIS
as a charge state booster. The most recent of these
research works is the implementation of the twofrequency
heating on an ECRIS. At the ISAC facility
of TRIUMF, a 14.5 GHz PHOENIX booster which has
been in operation since 2010 was recently upgraded
to accommodate the two-frequency heating system
using a single waveguide. The efficiency for charge
breeding into a single charge state, which depends on
the rare isotope that is being charge-bred, has been
determined to be between 1 - 6 %. The CSB is being
upgraded to improve its charge breeding efficiency. A
detailed investigation of the effect of the twofrequency
heating technique on the intensity,
emittance and the efficiency of the extracted beam is
presently being conducted.

Speaker: Joseph Adegun (TRIUMF)

14:35 → 14:45 Studies of ECR Plasma Chamber Contamination With Accelerated Beams and Diamond Detectors

While developing stable and re-accelerated rare
isotope beams (RIB) for acceleration with the TAMU
K500 cyclotron, a background of various stable
beams has been observed. It has been determined
that this background is arising from alloys and
contamination in the components of our ECR ion
sources, in particular, the aluminum alloy plasma
chamber. We have developed a detector system
based on diamond detector telescopes that allows us
to measure the composition of the beam after
acceleration with the K500 cyclotron at TAMU. Using
this technique, we have been able to develop ion
source and cyclotron tuning methods to minimize the
stable beam background and maximize the stable
beams of interest and/or the RIBs. We also endeavor
to reduce the stable beam background from the ECR
ion sources using techniques such as pure aluminum
liners. In my presentation, I plan to show our
accelerated beam detection setup with diamond
detectors. I also plan to present about the
background we have measured with this setup from
the ECRIS components, in particular, the plasma
chamber. Finally, I will comment on our efforts to
reduce this background.

Speaker: Brian Roeder (Texas A&M University)

14:45 → 15:05 Break

15:05 → 15:35 Closing Statement

15:35 → 15:55 FRIB Tour Presentation

15:55 → 16:55 FRIB Virtual Tour

16:55 → 16:56 Adjourn