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The Atomki accelerator center
I. Vajda, Zs. Fülöp, and S. Biri
Citation: AIP Conference Proceedings 1852, 060002 (2017); doi: 10.1063/1.4984866
View online: http://dx.doi.org/10.1063/1.4984866
View Table of Contents: http://aip.scitation.org/toc/apc/1852/1
Published by the American Institute of Physics
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The Atomki Accelerator Center
I. Vajdaa), Zs. Fülöpb), S. Biric)
MTA Atomki, Institute for Nuclear Research, Hungarian Academy of Sciences,
H-4001 Debrecen, P.O. Box 51, Hungary
a)
vajda.istvan@atomki.mta.hu
fulop.zsolt@atomki.mta.hu
c)
biri.sandor@atomki.mta.hu
b)
Abstract. Particle accelerators are the driving forces of nuclear physics laboratories and MTA Atomki, the Institute for
Nuclear Research of the Hungarian Academy of Sciences is no exception. The Atomki Accelerator Center (AAC)
incorporates several low-energy charged-particle accelerators, offering the possibility of choosing ions with various
charge states, energies and beam intensities. Currently, the AAC has six main facilities: a cyclotron (K=20), two Van de
Graaff accelerators (1 MV, 5 MV), an ECR ion source, an electromagnetic isotope separator and a 2 MV Tandetron
installed in 2015. The accelerators, spanning a range of beam energies from 50 eV to 27 MeV, have been designed for a
broad range of research projects and applications in various fields – mainly in nuclear and atomic physics, materials
science, environmental research and archaeology. The structure of the laboratory with a short description of the most
important topics, education and outreach activities are presented.
INTRODUCTION
Atomki, the Institute for Nuclear Research of the Hungarian Academy of Sciences (MTA) [1] was founded in
1954. The witness of these times is the 800 kV cascade generator, which peacefully rests in the garden after being
decommissioned in 1992. In front of the generator is a plaque indicating that in 2013 this building was declared a
Historic Site, the first such memorial in Hungary, by the European Physical Society. The plaque commemorates the
Debrecen neutrino experiment carried out by A. Szalay and his Ph.D student J. Csikai, in 1956, a revolutionary year
in Hungary not only from the scientific point of view. The experiment used a cloud chamber to detect the beta decay
of 6He, in which the tracks of the electron and of the recoiled 6Li nucleus clearly demonstrate that there must be a
third, neutral, particle, invisible to the cloud chamber, carrying away momentum and energy. This observation
confirmed the existence of the (anti) neutrino, which, according to the EPS plaque, “laid a brick to the foundation of
modern physics.” Alexander Szalay, the father of nuclear research in Hungary, was also the founding director of
Atomki. His commitment to nuclear physics, and especially to nuclear experiments, dates back to 1936, when he
spent six months with Ernest Rutherford at Cavendish Laboratory in Cambridge, UK. Later he also had a pioneering
role in prospecting the uranium resources in Southern Hungary. He was the perfect person to be selected as director
of a newly established nuclear research institute. In the past sixty years Atomki gradually developed into an institute
with a broad research portfolio ranging from nuclear physics to atomic, particle, and environmental physics [2].
THE ATOMKI ACCELERATOR CENTER
Accelerator-based research and development have been playing a central role in the institute. In order to
reinforce the infrastructure backbone of Atomki in 2009 a new division was established in our institute: the Atomki
Accelerator Center (AAC). Before this time the facilities and staff of AAC belonged to other departments of the
Exotic Nuclei and Nuclear/Particle Astrophysics (VI). Physics with Small Accelerators
AIP Conf. Proc. 1852, 060002-1–060002-8; doi: 10.1063/1.4984866
Published by AIP Publishing. 978-0-7354-1526-3/$30.00
060002-1
institute. It was undersstood that the translocationn of all the accelerators intoo a centralizedd unit is advaantageous in
o domestic) ccan be easier
numerouss fields. For exxample, the suubmission of any instrumenntation type prroposal (EU or
and has a higher chancee to be supporrted. The orgaanization and ddistribution off the beam tim
mes will be morre equal and
optimal. The
T usage of the maintenannce and spare tools can become better annd cheaper. Thhe operating sttaff (cca. 20
persons) can serve at m
more than onee accelerator and
a the teams can help eachh other. The accelerator
a
cennter actually
became a basic unit of the institute besides the tradditional scientiific divisions from
f
2009 [1,3].
Fiigure 1. The loccation of the acccelerators at Atoomki
Atomki Acceleerator Center ((AAC) incorporates several low-energy ccharged-particlle acceleratorss (Figure 1),
The A
offering tthe possibility of choosing ioons with varioous charge stattes, energies aand beam intennsities (Figuree 2).
The use
u of the serrvices of the Atomki
A
Accelerator Centerr is managed by the Progrram Advisory Committee
(PAC). T
The services (within
(
the frrames of the capacities) arre available ffor everyone with equal chance if an
acceptablle scientific prrogram is provvided togetherr with the requuest. The servvices - both foor external or llocal users are availaable by filling out and e-sennding the Beam
mtime Requestt Form. The beeamtime and machine
m
time requests are
judged byy the PAC, If necessary thee PAC may deemand the reppresentatives oof the applyingg group to givve an oral or
written reeview of the pproposed reseearch. The PA
AC prepares a suggestion onn the amount of beamtime or machine
time and on the propossed beamtime fee. The final decision on thhe hours and on
o the expenses is made by the director
b seen in Figg. 3. Atomki
of Atomkki. Based on reequest, the used beamtime of the variouss accelerators of AAC can be
Accelerattor Center as R
Research Infraastructure is ppart of MERIL
L (Mapping of the Europeaan Research Innfrastructure
Landscappe) database, aas well.
All thhe beam-lines of the accelerrators are equiipped with staate-of-the art chambers
c
and detector systeems, such as
various ggamma, neutroon, and chargeed-particle dettectors, a spliit-pole magnettic spectrometter, electron-ppositron pair
spectromeeter, microbeaam, external bbeam, and soo on. Fast neuutron sources are installed as well. This accelerated
beam orieented techniquue is accompaanied by a widde range of staandalone devicces, for exampple, target prooduction and
analysis stations, matterial sciencees laboratory,, and noble gas and staable isotope mass spectroometers for
mental researchh [2,3].
environm
060002-2
Figure 2. The
T covered ennergy range annd the available ion species of the Atomkki accelerators
Figuure 3 Delivereed and schedulled beamtimess by the main A
Atomki acceleerators
060002-3
Description of the accelerators
1 MV Van de Graaff accelerator
Both the 1 MV and the 5 MV accelerators (VdG-1 and VdG-5, respectively) were designed and built in Atomki.
The smaller 1 MV generator was constructed as a test bench and using the experience there the 5 MV accelerator
was build later. The main parameters of the accelerator: Terminal voltage range 50-1500 kV; Energy stability < 10
keV; maximum beam (proton) intensity, direct 80 μA; maximum beam intensity, analyzed 12 μA; ion source:
inductively coupled RF source; ion range: H+, He+, C+, N+. There are two available beamlines, a time-of-flight
electron spectrometer is installed at the end of one. This Research Infrastructure (RI) is suitable for study of the
collision processes of energetic ( > 10 keV ) ions/atoms with free (gaseous) atoms and molecules. Information on
the collision processes is obtained by detection of the electrons emitted from the collisions. Accordingly, the central
element of RI is an electron spectrometer. This is supplemented by further elements which partly ensure the welldefined charged state of the bombarding ions, and partly make it possible to carry out coincidence measurements
between the emitted electrons and the ions scattered in the collisions.
5 MV Van de Graaff accelerator
The actual main parameters of the 5 MV accelerator: terminal voltage ranges between 1-3,5 MV; ion massenergy product 56 MeV x AMU/e2; Energy stability < 1 keV; maximum beam intensity, direct 50 μA; maximum
beam intensity, analyzed 10 μA; ion source: inductively coupled RF source; ion range H+, D+, He+, C+, N+, O+,
Ne+. This accelerator has been the basic instrument of our research infrastructure from the beginning, serving
generations of researchers in a large number of research topics. The accelerator have three beamlines, partly serving
atomic physics, nuclear physics [4] and nuclear astrophysics [5] experiments, and partly accommodating instruments
for microbeam applications used in elemental analysis and in the production of microstructured devices.
The activity of Laboratory of Ion Beam Applications (IBA Lab) is mostly based on the usage of the 5 MV
accelerator. Through determining the concentration and distribution of elements, ion beam analytical techniques can
give information on provenance, authenticity, production technology, and degradation due to environmental effects
of art and archaeological objects. They also contribute to the elaboration of conservation technologies. Besides the
in-vacuum measurements with high lateral resolution, an external micro-beam set-up is also available for artefacts of
bigger sizes or sensitive nature. The IBA Lab served as a transnational access facility within the EU FP7
CHARISMA infrastructure project. Within EU H2020 IPERION CH, besides the transnational access service and
networking, the IBA Lab also participates in joint research activities [6].
Proton Beam Writing (PBW) is a direct write lithography technique, that requires the same infrastructure as is
available in our laboratory for IBA. Using the fine focused ion beam, we can produce microstructures for various
purposes, e.g. creating a micro-fluidic device for filtering circulating tumor cells out of human blood.
The K = 20 MGC-20E cyclotron
The Cyclotron Laboratory has been in service since 1985, and it is still the highest energy particle accelerator in
Hungary. The basic equipment of the Cyclotron Laboratory of Atomki is a Russian made MGC-20E isochronous
particle accelerator. It can accelerate protons, deuterons, He-3 and He-4 particles up to a max. proton energy of 18
MeV (20 MeV internal proton energy) and extracted beam current of 50 microamperes. 9-10 experimental stations
belong to it equipped with different measuring devices and run by different groups. The separation of radioisotopes
from the targets irradiated with the 20 MeV cyclotron of Atomki is carried out in the B level Radiochemistry
Laboratory. Several of these radioisotopes have been used for labelling radiopharmaceuticals synthesized for human
diagnostic (PET: 11C, 18F, 61Cu, 64Cu, 76Br, 124I; SPECT: 123I, 111In) and therapeutic (103Pd, 131Cs, 165Er, 169Y, 186Re,
210
At) examinations. Radioactive water samples are also analyzed in the Laboratory.
Important elements of the portfolio of neutron sources in Hungary are operating at the cyclotron of Atomki:
x
Quasi-monoenergetic fast neutron source. It has a D2-gas target and, using deuteron bombarding beams,
quasi-monoenergetic neutrons can be produced in the En = 3 - 12 MeV neutron energy range. The energy
and intensity of the emitted neutrons can be controlled via changing the energy and intensity of the deuteron
060002-4
bombarding beam. About three orders of magnitude of intensity range can be covered. Additionally, well
characterised broad spectrum d+Be neutrons can be produced at the same measuring site. A pneumatic
rabbit system is available enabling counting short lived radioactive products when the activation technique
is used. Applications: measurement of excitation function of neutron induced nuclear reactions, calibration
of detectors, measurement of response functions, benchmark tests, fast neuron activation analysis (FNAA),
dosimetry, radiobiology.
x
Cyclotron neutron source with beryllium target. High intensity fast neutrons are produced via bombarding a
3 mm thick Be-target with charged particle beams. Using 18 MeV protons the broad n-spectrum covers the
En = 0 - 16 MeV energy range and, for 10 MeV deuterons, the En = 0 - 12.5 MeV energy range. The neutron
spectrum can be controlled via changing the type and energy of the bombarding beam. Typical intensity
within a cone of 10o half angle around the zero degree direction is 3x1011 n/s/sr for Ep = 18 MeV protons.
Applications: fast neuron activation analysis (FNAA), dosimetry, radiobiology, radiomutation breeding of
plants, irradiation tests of insulators and semiconductor based electronics-photonics structures and devices
used in high energy physics and space research and applications.
Electron Cyclotron Resonance ion source
In the ECR Laboratory of Atomki operates the only Hungarian electron cyclotron resonance (ECR) ion source
(ECRIS) [7]. The ECR ion source is a middle-size facility and, contrary to its name, is a low energy particle
accelerator devoted to produce and deliver plasmas and ion beams in wide range of the elements, charges at low
energies. Plasma and ion choice: H, He, N, O, Ne, Ar, Kr, Xe (from gases) és Ni, Fe, Zn, C, C60, Zn, Pb (from
solids). The energy and charge of the ion beams can be varied up to an upper limit. The highest achieved charge so
far has been 27 which is Hungarian record. The beam energy can be changed between 50 eV and 1 MeV,
continuously. In the laboratory numerous atomic and plasma physics investigations are beeing carried out, e.g.
plasma diagnostics, X-ray spectroscopy, ion-surface and ion thin layer interactions, the production of new materials.
The plasmas and ion beams can cover the surfaces of industrial and medical samples thus their properties can be
modified.
2.0 MV Medium-Current Plus Tandetron Accelerator
In May 2014 Atomki installed its new Tandetron accelerator produced by High Voltage Engineering Europa
BV. In January 2015 a duoplasmatron ion source with the injector magnet, and a simple temporary switching
magnet were installed. The Tandetron accelerator needs negative ion input and then produces high energy positive
ion beam (in this case protons). The preliminary arrangement immediately allowed to start developing an external
beam setup for archeology and a target chamber for nuclear astrophysics. The first scientific result made in this
target chamber was presented at the European Nuclear Physics Conference EuNPC2015 in Groningen, the
Netherlands and it was awarded the "Best poster prize".
In May 2015 we installed a 9-port switching magnet directly at the exit of the Tandetron, i.e. to a temporary
position. Presently there are four beamlines built on the switching magnet: nuclear physics, nuclear astrophysics,
external beam, and a newly developed scanning ion nanoprobe setup. The nanoprobe ion optics is based on the
existing microprobe system, that has been operational for the past 20 years on the 5 MV Van de Graaff machine, and
served numerous projects and PhD topics. All the above mentioned equipments have been funded by the
infrastructure grants of the Hungarian Academy of Sciences.
With the financial support from the Hungarian Governmentwithin the frame of the Economic Development and
Innovation Operational Programme (GINOP) grant and co-funded by the EU, we plan to upgrade the present setup
with a multicusp ion source and a 90-degree analyzing magnet. The multicusp ion source cabinet (red box in Fig. 4)
will contain a +/- 30 degree magnet that allows to select the hydrogen or the helium source. The duoplasmatron ion
source will be upgraded to a cesium sputtering ion source, that is capable to produce negative ion beams from most
of the heavy elements. On the high energy side of the Tandetron the 90-degree analyzing magnet will be installed.
We will move the switching magnet from the present (temporary) position to the exit of the analyzing magnet. The
nanoprobe will be moved to the new position on the right 10-degree line of the switching magnet. The microprobe
will be moved to this new Tandetron Laboratory from the old Van de Graaff Laboratory, thus allowing much better
060002-5
quality ioon beam (stabiility, beam sizze, etc). The new analytical endstation wiill be installedd on one of thee beamlines.
Several oother beamlinees will be availlable for preseent and future users both intternal and exteernal. The vaccuum system
that is neccessary for thiis is shown wiith red lines.
Fiigure 4. Tandetrron lab planned layout Phase 1+
+2+3
MV Medium-C
Current Plus Taandetron Acceelerator System
m has low ripple kit and active stripper
The innstalled 2.0 M
gas pressuure control. Thhe performancce of the systeem is better thaan the values ddescribed in thhe HVEE speccifications:
x
x
x
teerminal voltagge (TV) ripple: 25 VRMS, we measured bettter than 15 VRMS
R
T stability wiith generating voltmeter stabbilization +/- 2200V, measured value betteer than +/- 50V
TV
V
trransmitted prooton beam currrent measuredd at zero degree high energy end faraday cup
c higher thann 25 μA
The measurements
m
were perform
med together with the instaallation enginneer, over onee hour, after one
o hour of
warmiing up by thee Generating V
Volt Meter (G
GVM) and at 75% of maximum terminaal voltage by means of a
Capaccitive Pick-up Unit (CPU). T
The measured values are shoown in Fig. 5.
060002-6
F
Figure 5. Terminnal voltage stabbility of the Atom
mki Tandetron,, see text for dettails
Accelerrator Mass Speectrometer
In adddition to the m
multipurpose aaccelerators, a state-of-the-aart 14C analysiss technique wiith a compact MICADAS
type AMS (Acceleratoor Mass Specttrometer) withh a fully equippped sample-ppreparation laaboratory was installed in
2011 as a joint venture with the comppany ISOTOP
PTECH [3].
Educaation and outreach
o
Ever since
s
its founddation, Atomkki has been conntributing substantially to edducation of phhysics at the U
University of
Debrecenn (UD). The trraining of junior scientists at the postgraaduate level iss an essential ppart of the activity of the
Institute. Our researcheers play a signnificant role inn the Physics PhD School of
o UD. The PhD students get
g access to
the high-tech laboratorries and reseaarch infrastruccture of Atom
mki. They are of course inttegrated into the
t research
groups. M
Many of them choose subjeccts that allow tthem to obtainn expertise in the use of acccelerators and acceleratorbased tecchnologies. Researchers at Atomki partiicipate in unddergraduate teeaching, mainnly in the Department of
Environm
mental Physicss, which is runn jointly by Atoomki and the U
University of Debrecen.
Sciencee on Stage festtival 2017
Sciencce on Stage E
Europe providees a Europeann platform for science teachhers to exchannge teaching cconcepts and
to share ideas. The ulltimate goal is to improve science teachhing by encouuraging creatiivity in sciennce teachers.
Through this we will encourage
e
moore schoolchildren to considder a career iin science or engineering bby spreading
good teacching concepts among Euroope’s science teachers. Scieence on Stagee Europe proviides a Europeean platform
for sciencce teachers to exchange teacching conceptts and to sharee ideas. Our innstitute will coo-organize thee 2017 event
of the Sccience on Stagge festival in Debrecen, whhere 350 teacchers from 25 countries com
me together tto share and
exchangee their ideas annd concepts onn successful sccientific educaation. [8]
060002-7
Accelerator labs as outreach tools
Besides the above mentioned traditional channels, Atomki has set out to target secondary school pupils using
unconventional methods more suited to the attitude of the computer-age generation. An interactive computer game
entitled Miazma was prepared in 2015 in cooperation with a professional IT company [9]. The story line of the game
combines both real and fictitious elements, the player has to unveil mysteries using elementary school physics skills
and combining information obtained from the researchers of Atomki. The central objects of the story are enigmatic
meteorites, similar to the one that landed near Debrecen in 1857, and the player learns not only about modern
physical equipment by which the elemental composition of various samples can be analyzed in our institute, but also
about the scientific history of Debrecen, in which the Reformed College of Debrecen has been playing a central role
since its foundation in 1538. As another effort to promote science among the even younger generation, a short
animated movie entitled Lab Story was created in 2010, in which kids can learn about the adventures of curious
Helium atoms in various laboratories of Atomki [1].
SUMMARY
Atomki Accelerator Center is growing steadily and is characterized by infrastructure-driven topics and it has
open access with PAC. The MGC-20E cyclotron produces accelerated particle beams for both fundamental and
applied research, as well as for medical and industrial applications. Owing to its sophisticated beam transport system
equipped with advanced beam diagnostics, the beam parameters can be flexibly adjusted to the diverse requirements
of research and application projects, making it a multidisciplinary facility. The new Tandetron Laboratory is a stateof-the-art ion beam facility, serving various research topics and numerous research groups.
The scientific activity has strong interdisciplinary aspects. Atomki and AAC have collaborations worldwide and
efficient use of local resources, it creates the opportunity to open new topics and new collaboration.
ACKNOWLEDGEMENTS
The authors would like to thank the all colleagues of the Atomki who have contributed to this work, especially
to: I. Rajta: TANDETRON project leader, Z. Szikszai: CHARISMA-IPERION PI, Gy. Gyürky: Nuclear
astrophysics PI, G. Lévai: Nuclear Physics News paper coauthor, M. Hunyadi: editor of Atomki booklet 2014.
Financial support is acknowledged from GINOP-2.3.3-15-2016-00005.
REFERENCES
1.
2.
3.
4.
5.
6.
7.
8.
9.
http://www.atomki.hu/
Zs. Fülöp and G. Lévai, Nuclear Physics News 25, 5 (2015)
https://www.atomki.mta.hu/en/reviews/
A. Krasznahorkay et al., Phys. Rev. Letters 116, 042501 (2016)
G. G. Kiss et al., Phys. Rev. Letters 101, 191101 (2008)
http://www.iperionch.eu/
Biri S., Rácz R., Pálinkás J., Review of Scientific Instruments 83, 02A:341 (2012)
http://www.science-on-stage.eu/
http://gamedev.privatemoon.com/en/fomenu1/miazma-links
060002-8
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