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24th symposium of the Hellenic Nuclear Physics
Society Ioannina, 22-23 May, 2015
Dr. Anastasios DimitriouUniversity of Crete
&Institute of Nuclear and Particle Physics, Demokritos, Athens
Atomic Physics at the 5MV Tandem at Demokritos: The UOC APAPES project
Present Status of APAPES History and future
Presentation by Dr. Anastasios Dimitriou (Univ. of Crete)Post Doctoral researcher of APAPES
24th symposium of the Hellenic Nuclear Physics Society- Ioannina, 22 May 2015
Atomic Physics with Accelerators
First time in Greece.
Basic understanding of atomic collision processes (simpler systems, isoelectronic studies).
High Resolution Zero-degree Auger Projectile Spectrometry (ZAPS) from collisions of He-like ions with gas targets. Non-statistical production of 1s2s2p 4P and 1s2s2p 2P states by e- capture to the 1s2s 3S state.
Charged particle optics. Development and modeling of electron spectrometers. Simulations and experiments. (comparison with recent and older measurements).
Ongoing research at Demokritos Infrastructure (installation of terminal and post strippers).
24th symposium of the Hellenic Nuclear Physics Society- Ioannina, 22 May 2015
Basic ion-atom collision processes
continuum
K
LM
Kcapture
K-M excitation
Ea - Auger energy
KLM Auger
transition
e-e interaction
AtomicEnergylevels
Kionization
Atomic Structure: q, Zp, Zt , Ex, Ea…Collision Dynamics: b, Vp , vt …Cross section: HCI: Few-electrons much simpler environment for testing theoriesSpecial interest: Two-electron processes, electron correlations and deviations from the independent particle model
,...),,,v,,,,( xEEZbZqV attpp
M-K radiativetransition
Ex
VpZp
Zt
b
e- e-
Ion-atom collision
vt
ProjectileIon
Charge q+ TargetAtom
24th symposium of the Hellenic Nuclear Physics Society- Ioannina, 22 May 2015
http://apapes.physics.uoc.gr/
24th symposium of the Hellenic Nuclear Physics Society- Ioannina, 22 May 2015
THALES 2011-2015: APAPES
• University of Crete• Tandem Laboratory – INPP Demokritos• University of Ioannina
600k€ - experiment at 5 MV Tandem
Atomic Physics with Accelerators: Projectile Electron Spectroscopy
Main team
Dept. of Physics, Univ. of Crete, Heraklion
Theo Anastasios Ioannis Angelos Spiros Eleonore Zouros Dimitriou Madesis Laoutaris Doukas Defaux (Prof & PI) (PostDoc) (PhD student) (MS student) (MS student) (3-month practice) Univ of Ioannina ENSICAEN
24th symposium of the Hellenic Nuclear Physics Society- Ioannina, 22 May 2015
Support Team
5MV Tandem, Institute of Nuclear and Particle Physics NCSRT Demokritos
Dr. Sotiris Dr. Tasos Dr. Michalis Miltos Theo Harissopulos Lagoyannis Axiotis Andrianis Mertzimekis (Director) (Res.) (Res.) (Accel. Eng.) (Prof.)
Univ. of Athens
24th symposium of the Hellenic Nuclear Physics Society- Ioannina, 22 May 2015
Manolis Bela Omer Genoveva Jose Benis Sulik Sise Martinez-Lopez Paulo Santos (Prof) (Prof) (Prof) (Prof) (Prof)
other importantparticipants
Dept of PhysicsUniv of Ioannina Greece
ATOMKIDebrecenHungary
Univ of Isparta Turkey
Dept Fisica Aplicada Madrid,
Spain
Dept de FisicaUniv Nova de Lisboa Portugal
Experiment CPO simulationsZoom lenses
AtomicStructurecalculations 24th symposium of the Hellenic Nuclear Physics Society- Ioannina, 22 May
2015
APAPES: New beam line for atomic physics
November 2011 May 2013
November 2013
24th symposium of the Hellenic Nuclear Physics Society- Ioannina, 22 May 2015
GREEN target room
RED target room
TANDEM Hall
SF6 storage room
35.45 m
9.1
m
7.55m
16.9
m
17.4 m 17.3 m
14 m6
m
R60
R45R32.5o R15 L25
L45L60
Analyzing magnet
switching magnet
Sputter source
Duoplasmatronsource
Inflection magnet
Terminal stripper
Demokritos Setup – new beam line today!
24th symposium of the Hellenic Nuclear Physics Society- Ioannina, 22 May 2015
Demokritos Setup – Target 6-way cross and spectroscopy chamber
Turbo 70
Turbo 550
Spectrometer chamber
Gas cell
Beam direction
Baratron
24th symposium of the Hellenic Nuclear Physics Society- Ioannina, 22 May 2015
New ZAPS setup: Single stage 00 HDA with injection lens and 2-D position sensitive detector
5104.14
%,20%,1.0
acceptE
E
E
E
Gas in Pressure Gauge
Gas Cell
PSDX-PositionY- Position
Timing
4-element lens
Faraday Cup
Inner hemisphere
electrons
Outerhemisphere
APAPES (2015)
HCI
Target gas nt ~1012 #/cm3Differential
Pumpingports
Focusing and retardation
Chamber pressure~10-7 Torr
Overall efficiency gain ~ 200-500High Transmission ~ 90%
Paracentric entry
24th symposium of the Hellenic Nuclear Physics Society- Ioannina, 22 May 2015
DSP unit
DSP unit from ATOMKI
PreampsDSP unit
12V power supply
2-D image on PSD
X-proj
Y-proj
4P
Projection along energy axis 24th symposium of the Hellenic Nuclear Physics Society- Ioannina, 22 May
2015
Installation of ion beam stripers at the tandem
Terminal gas stripper. Placed inside the terminal and produces ground state beams (1s2).
Post foil stripper. Placed in the beam line of the terminal. Necessary to acquire He-like ions at lower energies.
Post Gas stripper. Placed in the beam line of the terminal in order to obtain mixed state beams (1s2, 1s2s) at different fractions and different intensities.
Charge analysis program TARDIS (Transmitted chARge DIStribution) used for calculation of the expected charge states after foil and gas stripping available in (http://apapes.physics.uoc.gr/) 24th symposium of the Hellenic Nuclear Physics Society- Ioannina, 22 May
2015
Experimental results
24th symposium of the Hellenic Nuclear Physics Society- Ioannina, 22 May 2015
0
1
2
3
4
5
6
2P-
Ne (20 mTorr) Fit
18 MeV C4+ W=1966eV, F=4
2P+
Nor
mal
ized
ele
ctro
n Y
ield
s (
10-1
1)
2S
4P
2D
0
1
2
3
Ne (20 mTorr) Fit
2S
4P
2P-
2P+2D
220 225 230 235 240 245 250
0
1
2
3
4
5
6
2P-
Ar (5 mTorr) Fit
2S
4P
2P+
2D
220 225 230 235 240 245 250
0
1
2
3
2P-
Ar (5 mTorr) Fit
12 MeV C4+ W=1521eV, F=4
Auger Electron Energy (eV)
2S
4P
2P+
2D
0
2
4
6
Norm.yields Norm.fit
Ne
12 MeV C4+ W=1521eV,F=4, VL4 =-684.45V,VL5=1399.32V
0
2
4
He4P
2P-2P+ 2D
0
2
4
Norm
aliz
ed e
lect
ron Y
ield
s (x1
0-11 )
(arb
.units
)
H2
2S
220 225 230 235 240 245 2500
2
4
Auger electron Energy (eV)
Ar
1. Auger Electron Spectra for C4+ mixed state beams in collisions with various targets at various Energies
2. Comparison with simulations (SIMION)
So far…..
• Presentations at international conferences: (CAARI-USA, HCI- Argentina, SPARC- Germany, CDAMOP- India,
PIPAMON- Hungary, SHIM- Germany etc)
• At least 7 more until September:• (ISIAC- Barcelona, ICPEAC- Toledo etc)
• 3 publications: M. Dogan et al, Rev. Sci. Instrum. 84 (2013) 043105 S. Doukas et al, Rev. Sci. Instrum. 86 (2015) 043111
O. Sise & T. Zouros, J. Spectroscopy 2015 in press • 1 participation in conference proceedings (HCI
2014): Ι. Madesis et al, JPCS 583 (2015) 012014• 3 more participation in conference proceedings in
progress (CDAMOP, PIPAMON). 24th symposium of the Hellenic Nuclear Physics Society- Ioannina, 22 May
2015
In the near future…
Finish the installation of terminal and post strippers.
Installation of Stepping Motor on the PSD in order to investigate the dependence of the energy resolution of the HDA from the distance of the PSD from the focal plane.
Investigation of the systematics of the 4P/2P ratio in an isoelectronic sequence study using He-like ions from Li+ , B3+ , C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u.
Use different targets such as H2, He, Ne, Ar.
24th symposium of the Hellenic Nuclear Physics Society- Ioannina, 22 May 2015
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program: THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289. 24th symposium of the Hellenic Nuclear Physics Society- Ioannina, 22 May
2015