1. K. Czerski Institute of Physics, University of Szczecin Euratom Workshop Szczecin, 23.03.2006 Deuteron Fusion Reactions in Metallic Environments

2. Electron Screening in Nuclear Reactions V(r) = exp (- r /a ) Z 1 Z 2 e 2 r r ≈ - U e R a screening energy U e = Z 1 Z 2 e 2 a s-wave penetration factor P(E)P(E) P(E+U e )

3. Experimental Set-Up 200 kV accelerator TU Berlin d d + +

4. Similar results: J. Kasagi et al., J.Phys.Soc.Jap. 71 (2002) 2281 F. Raiola et al., Eur.Phys.J. A13 (2002) 337 gas target K. Czerski et al., Europhys. Lett. 54 (2001) 449 metal targets d + d 3 He + n d + d 3 H + p U e = 25±5 eV U.Greife et al., Z.Phys. A351 (1995) 107 Enhanced Electron Screening Effect I F(E)F(E) enhancement factor : in metallic environments U e screening energy

5. εc(q)εc(q) Dielectric Function Theory  v =  c = 1 self-consistent charge formfactor z number of bound electrons k TF Thomas-Fermi wave number valence-electron dielectric function P(q) Lindhard RPA polarizability G(q) local field correction core-electron dielectric function from f-sum rule K. Czerski et al., Europhys. Lett. 68 (2004) 363

6. Enhanced Electron Screening Effect II Li Be Al Zr Pd Ta C D-D Potential dielectric-function theory Results K. Czerski et al., Europhys. Lett. 68 (2004) 363

7. Comparison of Experimental Results

8. Proposal I Experimental: new measurements under ultra-high vacuum conditions looking for the target material and temperature dependence Theoretical: improvement of the dielectric-function theory polarization of deuterons within the crystal lattice Collaboration University of Szczecin: Prof. K. Czerski, Prof. A. Bechler, Ż. Wyrwał-Artyszuk Technical University of Berlin: Prof. P. Heide, Prof. G. von Oppen, Dr. A. Huke Humboldt University of Berlin: Prof. H. Winter, Dr. M. Busch

9. Angular Distribution d + d 3 He + nd + d 3 H + p Ta a2a2

10. Energy Spectra

11. Suppression of Neutron Channel 16 transition matrix elements s, p und d waves channel spin S = 0,1,2 experimental results can be explained if S = 0 Polarisation von Deuteronen ? A. Huke, K. Czerski, accepted Eur. Phys. J. A

12. Proposal II Experimental: direct measurement of the neutron channel energy and target material dependence of the effect Theoretical: search for a theoretical explanation of the deuteron polarization within the crystal lattice Collaboration University of Szczecin: Prof. K. Czerski, Prof. R. Fedaruk, Prof. J. Stelmach Technical University of Berlin: Prof. P. Heide, Dr. A. Huke, L. Martin Humboldt University of Berlin: Prof. H. Winter, Dr. M. Busch