1. Diproton correlation in a proton-rich Borromean nucleus 17Ne
Tomohiro OishiA,
Kouichi HaginoA, Hiroyuki SagawaB
ATohoku Univ., BUniv. of Aizu
1. Introduction
2. Model
3. Results
4. Summary

2. 1.1 Dineutron correlation
Dineutron correlation in 2n-Borromean nuclei (theoretically predicted):
K.Hagino, and H.Sagawa, PRC72(‘05)044321
Remarkable localization of two neutrons
“dineutron correlation”.
How about two protons in a weakly bound system?

3. Ne nucleus (1)

4. 1.2 17Ne nucleus (2) Typical “2p-Borromean” nucleus; proton-unbound,
stable for proton emission.
17Ne is an ideal system to analyze diproton correlation.

5. 2.1 Three-body-model
Off-diagonal

6. 2.2 Pairing interaction Explicit Coulomb interaction
Density-dependent contact interaction
We need cutoff:EC to determine v0 (pairing in vacuum).
Other parameters are fixed to obtain g.s.energy of 17Ne: MeV.

7. 2.3 Single-particle basis
Woods-Saxon + Coulomb potential for p-Core

8. Averaged
Resonances

9. 2.3 Box-approximation Put infinite wall at r=Rbox:
 Continuum states are discretized.
Resonances of 16F at MeV (s1/2) and at MeV (d5/2) are reproduced.

10. 2.5 Expansion with s.p.basis
Determined by diagonalization
0+ configuration for g.s.

11. 3.1 Results (1)

12. Pairing gap of protons and neutrons
S.Hilaire et al., Phys.Lett.B531(2002)
Pairing gap of protons and neutrons
protons
neutrons

13. 3.2 Results (2)
“Diproton correlation”

14. 4. Summary
We performed three-body-model calculation for 17Ne with density-dependent contact pairing and the Coulomb interaction.
Coulomb repulsion contributes about 14% reduction to pairing energy.
Existence of strong “diproton correlation”.
Future works: application to 2p-emission.

15. Table of Nuclides , http://atom.kaeri.re.kr/ton/nuc6.html