anastasios lagoyannis tandem accelerator laboratory institute of nuclear physics

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Anastasios Lagoyannis Tandem Accelerator Laboratory Institute of Nuclear Physics N.C.S.R. “Demokritos” Recent Developments of the PIGE setup Recent Developments of the PIGE setup at the at the Tandem Accelerator Facility of Tandem Accelerator Facility of N.C.S.R. “Demokritos” N.C.S.R. “Demokritos”

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Recent Developments of the PIGE setup at the Tandem Accelerator Facility of N.C.S.R. “ Demokritos ”. Anastasios Lagoyannis Tandem Accelerator Laboratory Institute of Nuclear Physics N.C.S.R. “ Demokritos ”. Outline. The Tandem @ I.N.P. General Considerations for PIGE - PowerPoint PPT Presentation

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Page 1: Anastasios Lagoyannis Tandem Accelerator Laboratory Institute of Nuclear Physics

Anastasios LagoyannisTandem Accelerator Laboratory

Institute of Nuclear PhysicsN.C.S.R. “Demokritos”

Recent Developments of the PIGE setup at the Recent Developments of the PIGE setup at the Tandem Accelerator Facility of N.C.S.R. “Demokritos”Tandem Accelerator Facility of N.C.S.R. “Demokritos”

Page 2: Anastasios Lagoyannis Tandem Accelerator Laboratory Institute of Nuclear Physics

A. LagoyannisInstitute of Nuclear PhysicsNCSR “Demokritos”

OutlineOutline

The Tandem @ I.N.P.

General Considerations for PIGE

Target preparation and characterization

Charge measurement

Experimental Apparatus

Proposed measurements

Conclusions

Page 3: Anastasios Lagoyannis Tandem Accelerator Laboratory Institute of Nuclear Physics

A. LagoyannisInstitute of Nuclear PhysicsNCSR “Demokritos”

The 5.5 MV VdG Tandem accelerator @ I.N.P.The 5.5 MV VdG Tandem accelerator @ I.N.P.

Page 4: Anastasios Lagoyannis Tandem Accelerator Laboratory Institute of Nuclear Physics

A. LagoyannisInstitute of Nuclear PhysicsNCSR “Demokritos”

Basic Experimental ToolsBasic Experimental Tools

Page 5: Anastasios Lagoyannis Tandem Accelerator Laboratory Institute of Nuclear Physics

A. LagoyannisInstitute of Nuclear PhysicsNCSR “Demokritos”

General Considerations for PIGEGeneral Considerations for PIGE

Suitable Targets thin for resonances

thick for yield and validation

well characterized

Charge measurement Effective way of measuring the

current (cross checked if possible)

Experimental Apparatus High efficiency

Good resolution

Placed to appropriate angles

Analyzing Software

Page 6: Anastasios Lagoyannis Tandem Accelerator Laboratory Institute of Nuclear Physics

A. LagoyannisInstitute of Nuclear PhysicsNCSR “Demokritos”

Target PreparationTarget Preparation

Requirements Thin target i.e. Self – supported / Thin substrate

Chemical and Thermal stability

Electrical conductivity

Act as charge reference

Gold Tgt Carbon

Possible Solution

Stoichiometry ???

Thickness ???

BUT :

EvaporationResistiveElectron gun

Purchase

Evaporator @ I.N.P. Demokritos

Means of acquisition:

Page 7: Anastasios Lagoyannis Tandem Accelerator Laboratory Institute of Nuclear Physics

A. LagoyannisInstitute of Nuclear PhysicsNCSR “Demokritos”

Target CharacterizationTarget Characterization

X – Ray Fluorescence

Beam - less Using standards Unsuitable for Z < Al

Rutherford Back Scattering

Depth profiling Suitable for sandwich like targets Problematic for low Z

EBS and NRA

Depth profiling Depends on previous measurements Good for low Z

Page 8: Anastasios Lagoyannis Tandem Accelerator Laboratory Institute of Nuclear Physics

A. LagoyannisInstitute of Nuclear PhysicsNCSR “Demokritos”

Charge measurement ICharge measurement I

Traditional way(s)

Sophisticated Faraday cups

Suppression voltages (collimator and target)

Bending magnets

AlternativesSurface barrier detector at backward angles

Beam Chopper

Independent of the target

Use of the RBS technique with a heavy element on target

Downsides

Insulating targets

Change of beams’ charge

Page 9: Anastasios Lagoyannis Tandem Accelerator Laboratory Institute of Nuclear Physics

A. LagoyannisInstitute of Nuclear PhysicsNCSR “Demokritos”

Charge measurement IICharge measurement II

Beam Chopper

Periodic movement In/Out (programmable)

Wing: Thin Au layer on Al

A SSB detects the backscattered from Au

Coincidence signals for In/Out

No additional NIM modules

Needs calibration at the beginning

Page 10: Anastasios Lagoyannis Tandem Accelerator Laboratory Institute of Nuclear Physics

A. LagoyannisInstitute of Nuclear PhysicsNCSR “Demokritos”

Experimental apparatusExperimental apparatus

Electronically controlled turntable

Initial angles: 0o – 55o – 90o - 165o

4 HPGe detectors (1 – 80%, 3 – 100%)

2 Compton suppression BGO’s

Possibility of mounting backward Si detector

Possibility of mounting Si annular detector

Air / Water cooled target

NIM electronics

Singles Fast ADC DAQ

CAMAC event by event DAQ

Page 11: Anastasios Lagoyannis Tandem Accelerator Laboratory Institute of Nuclear Physics

A. LagoyannisInstitute of Nuclear PhysicsNCSR “Demokritos”

Experimental ProcedureExperimental Procedure

Preparation/characterization of the targets

Energy and Efficiency calibration of Ge detectors using point sources

Q x Ω calculation for the Si detector using RBS spectra from gold

Determination of Q using chopper and RBS technique

Machine calibration using either 27Al(p,γ) or threshold reactions

Peak analysis using two different algorithms to account for the bias error

Data validation using thick targets and appropriate software

Page 12: Anastasios Lagoyannis Tandem Accelerator Laboratory Institute of Nuclear Physics

A. LagoyannisInstitute of Nuclear PhysicsNCSR “Demokritos”

Proposed Measurement for Proposed Measurement for 3232SS

Experiment

Energy range : 3000 – 7000 keV

Steps: Varying (excitation function depending)Target: sandwich like Ta – TiS - Carbon C. Tsartsarakos et al. NIM B45 (1990), 33

Angle: 55o

Candidates:

32S(p,p’γ) 32S Εγ = 2230 keV

32S(d,pγ) 33S Εγ = 841 keV

32S(p, γ) 33S

Z. Elekes et al. NIM B168 (2000), 305

No PIGE related publications

C. Tsartsarakos et al. NIM B45 (1990), 33

Page 13: Anastasios Lagoyannis Tandem Accelerator Laboratory Institute of Nuclear Physics

A. LagoyannisInstitute of Nuclear PhysicsNCSR “Demokritos”

Candidates:

Proposed Measurement for Proposed Measurement for 1010B - B - 1111BB

10B(p,αγ) 7Be Εγ = 429 keV

10B(p,p’γ) 10B Εγ = 718 keV

R. Mateus et al. NIM B219 (2004), 519

V. Michaud et al. NIM B85 (1994), 881

C. Boni et al. NIM B35 (1988), 80 T. R. Ophel et al. Nucl. Phys. 33 (1962), 198

T. R. Ophel et al. Nucl. Phys. 33 (1962), 198

11B(p,γ) 12C Εγ = 11.68 MeV M. Koerdel et al. NIM B261 (2007), 520

11B(p,p’γ) 11B Εγ = 2125 MeV C. Boni et al. NIM B35 (1988), 80

Page 14: Anastasios Lagoyannis Tandem Accelerator Laboratory Institute of Nuclear Physics

A. LagoyannisInstitute of Nuclear PhysicsNCSR “Demokritos”

Proposed Measurement for Proposed Measurement for 1010B - B - 1111BB

C. Boni et al. NIM B35 (1988), 80 V. Michaud et al. NIM B85 (1994), 881

10B(p,αγ) 7Be

11B(p,p’γ) 11B

11B(p,p’γ) 11B

10B(p,p’γ) 10B

10B(p,αγ) 7Be

R. Mateus et al. NIM B219 (2004), 519

Experiment

Energy range : 1000 – 5000 keV

Steps: Varying (excitation function depending)

Target: 11B, 10B on thick Ta

Angle: 55o

10B(p,αγ) 7Be

Page 15: Anastasios Lagoyannis Tandem Accelerator Laboratory Institute of Nuclear Physics

A. LagoyannisInstitute of Nuclear PhysicsNCSR “Demokritos”

Experiment

Energy range : 1000 – 5000 keV

Steps: Varying depending on the excitation function

Target: Gold on 13C foil

Angle: 55o - 90o - 125o

Candidates:

Proposed Measurement for Proposed Measurement for 1313CC

13C(p, γ) 14N on 1.75 MeV resonance 90% Εγ = 9.16 MeV J. B. Marion et al. Phys. Rev. 104 (1956), 1028

H. H. Woodbury et al. Phys. Rev. 92 (1953), 1199

Page 16: Anastasios Lagoyannis Tandem Accelerator Laboratory Institute of Nuclear Physics

A. LagoyannisInstitute of Nuclear PhysicsNCSR “Demokritos”

ConclusionsConclusions

Means for target characterization

Effective charge measurement

Efficient HPGe experimental setup

A set of case studies

Appropriate software for validation

PIGE cross sections

Summary

Page 17: Anastasios Lagoyannis Tandem Accelerator Laboratory Institute of Nuclear Physics

A. LagoyannisInstitute of Nuclear PhysicsNCSR “Demokritos”

CollaboratorsCollaborators

A. Axiotis, V. Paneta and S. Harissopulos

M. Kokkoris

P. Misaelides