Studied in Metallic Environments 3 He + n d d + 3 H + p + Konrad - - PowerPoint PPT Presentation

Effects of a Threshold Resonance in the DD Reactions Studied in Metallic Environments

d d + +

3He + n 3H + p

1

Konrad Czerski

September 14-18, 2015

penetration factor through the Coulomb barrier

         E E E E E P

G G

exp ) (

V(r)

• 50 MeV

r

E ... depends on the plasma temperature

T (Sun) = 15 million deg V(r) =

Z1 Z2 e 2 r

Tunnel Effect

2

Electron Screening in Nuclear Reactions

V(r)

• 50 MeV

r V(r)

• 50 MeV

r

V(r) = exp (- r /a )

Z1 Z2 e 2 r Z1 Z2 e 2 r

≈

• Ue

R a screening energy

Ue =

Z1 Z2 e 2 a

         E E E E E P

G G

exp ) (

s-wave penetration factor

P(E) P(E+Ue)

3

Experimental Results (HV)

   

   cos 1

2 2P

A d d

tot

  

angular distribution

A2

4

EPL 2001

Experimental Results (HV) II

NIC 1998, p. 152

• Europhys. Lett. 54 (2001) 449

Similar results:

• J. Kasagi et al., J.Phys.Soc.Jap. 71 (2002) 2281
• F. Raiola et al., Eur.Phys.J. A13 (2002) 337
• F. Raiola et al., Eur.Phys.J. A19 (2004) 283

gas target metal target

d + d

3He + n

d + d

3H + p

Ue = 25±5 eV

U.Greife et al., Z.Phys. A351 (1995) 107

5

Experimental (HV) and Theoretical Results

20 40 60 80 100 50 100 150 200 250 300 350

Li

theo exp

Al Ta Pd Zr Al Screening Energy (eV) Atomic Number Z Li Zr Pd Ta

1.0 1.5 2.0 2.5 3.0 3.5 4.0 50 100 150 200 250 300 350

TF theo exp

Li

Polarisation Screening Energy (eV)

rs Ta Pd Al Zr

dielectric function theory: free and bound electron polarization cohesion screening

• Europhys. Lett. 2004, Phys. Rev. C 2008

electron-gas parameter rs

3 / 1

1 4 3 a n rs           6

UHV Experimental Setup

ECR ion source analyzing magnet electron detector target chamber mass spectrometer

I: 10-30 µA V: 30 kV V: ~ 1 V p: 10-11 – 10-10 mbar

7

UHV Results

8

200 400 600 800 20000 40000 60000 80000

Counts

Electron Energy (eV)

Zr

Ue = 497 ± 7 eV

with LN2 cooling pH2O ~ 5x10-12 mbar Auger electron spectroscopy

Ue (HV)  300 eV Ue (theo)  97 eV

EPJ A, 2011

Compund Nucleus 4He

9

Nuclear Molecule States

Correlation diagram for the valence particle in the nuclear two-center system

10

r d + d structure

UHV Electron Screening – Resonance Contribution

5 10 15 20 25 30 80 85 90 95 100 105 110

Cross Section (arb. units) Energy (keV)

Enhancement Factor

interference effect

2

Zr

Ue = 130 eV

11

p=20 meV 16 matrix elements Tβα = <2Sα+1LαJ|Jπ|2Sβ+1LβJ >

5 10 15 20 25 0.8 1.0 1.2 1.4 1.6 1.8 2.0 exp screening screening & resonance resonance

Enhancement Factor Deuteron Energy (keV)

eLBRUS: scheme

Accelerator with Ultra High Vacuum

Nuclear Power Nuclear&Medical Physics Nanoscopic Material Modification Radiospectroscopy NMR & EPR Laser Diagnostics Polymer Physics

Unique combination of research methods of nuclear physics with methods

• f solid-state physics and laser optics for study of the condensed hard,

soft and biological matter

e

Laboratoria Badawczo- Rozwojowe Uniwersytetu Szczecinskiego

12

eLBRUS: realization

13

Laboratory of Nuclear and Medical Physics

accelerator with ultra high vacuum

prototype ECR ion source low emittance , high current, light ions – a few mA Dreebit, Dresden, Germany

p = 10 -11 mbar

Equipment: Electron Auger Spectroscopy XPS, UPS scanning pulsed Argon gun – ToF spectr. mass spectroscopy

PREVAC, Poland

Cross Sections @ 1 keV

10 20 30 40 50 60 0.6 0.8 1.0

npBranching Ratio ELAB(keV) resonance+direct Sr Ta

proton channel (a2/a0) E(keV)

a2/a0 neutron channel E(keV) Sr Ta

16 transition matrix elements

neutron channel proton channel branching ratio APP B 2014

eLBRUS : Dual Fluid Reactor

& chromosome aberrations

People

TU Berlin, IFK Berlin U Szczecin

• K. Czerski
• K. Czerski
• A. Huke
• N. Targosz
• P. Heide
• A. Kilic
• D. Weißbach
• M. Kaczmarski
• A. Kowalska
• W. Pereira

TRIUMF, Vancouver HU Berlin

• G. Ruprecht
• H. Winter
• L. Martin
• D. Blauth

Electron Screening

17