220 likes | 239 Views
Double Beta Decay and Physics beyond the Standard Model Amand Faessler Tuebingen. Accuracy of the Nuclear Matrix Elements. It determines the Error of the Majorana Neutrino Mass extracted. O νββ -Decay (forbidden). only for Majorana Neutrinos ν = ν c. P. P. Left. ν. Phase Space
E N D
Double Beta DecayandPhysics beyond the Standard ModelAmand FaesslerTuebingen Accuracy of the Nuclear Matrix Elements. It determines the Error of the Majorana Neutrino Mass extracted Amand Faessler, München, 24. November 2005
Oνββ-Decay (forbidden) only forMajoranaNeutrinos ν = νc P P Left ν Phase Space 106x2νββ Left n n Amand Faessler, München, 24. November 2005
GRAND UNIFICATION Left-right Symmetric Models SO(10) Majorana Mass: Amand Faessler, München, 24. November 2005
P P e- ν ν e- L/R l/r n n Amand Faessler, München, 24. November 2005
L/R l/r P P l/r ν light ν heavy N Neutrinos l/r n n Amand Faessler, München, 24. November 2005
Supersymmetry Bosons↔ Fermions ----------------------------------------------------------------------- Neutralinos Neutralinos P P e- e- Proton Proton u u u u d d Neutron Neutron n n Amand Faessler, München, 24. November 2005
Theoretical Description:Simkovic, Rodin, Benes, Vogel, Bilenky, Salesh,Gutsche,Pacearescu, Haug, Kovalenko, Vergados, Kosmas, Schwieger, Raduta, Kaminski, Stoica, Suhonen, Civitarese, Tomoda, Valle, Moya de Guerra, Sarriguren et al. Never in Tuebingen: Muto/Tokyo, Hirsch/Valencia P k 0+ P e2 k e1 k ν Ek 1+ 2- n n Ei 0+ 0+ 0νββ Amand Faessler, München, 24. November 2005
Neutrinoless Double Beta- Decay Probability Amand Faessler, München, 24. November 2005
Effective Majorana Neutrino-Mass for the 0nbb-Decay Tranformation from Mass to Flavor Eigenstates CP Amand Faessler, München, 24. November 2005
Bilenky, Faessler, Simkovic:, Phys.Rev. D70:033003(2004) : hep-ph/0402250 Amand Faessler, München, 24. November 2005
The best choice: Quasi-Particle- • Quasi-Boson-Approx.: • Particle Number non-conserv. (important near closed shells) • Unharmonicities • Proton-Neutron Pairing Pairing Amand Faessler, München, 24. November 2005
g(A)**4 = 1.25**4 = 2.44 fit to 2nbb Rodin, Faessler, Simkovic, Vogel, Mar 2005 nucl-th/0503063 Amand Faessler, München, 24. November 2005
2.76 (QRPA) 2.34 (RQRPA) Muto corrected Amand Faessler, München, 24. November 2005
M0ν (QRPA)O. Civitarese, J. Suhonen, NPA 729 (2003) 867 Nucleus their(QRPA, 1.254)our(QRPA, 1.25) 76Ge 3.33 2.68(0.12) 100Mo 2.97 1.30(0.10) 130Te 3.49 1.56(0.47) 136Xe 4.640.90(0.20) • g(pp) fitted differently • Higher order terms of nucleon Current included differently with Gaussian form factors based on a special quark model ( Kadkhikar, Suhonen, Faessler, Nucl. Phys. A29(1991)727). Does neglect pseudoscalar coupling (see eq. (19a)), which is an effect of 30%. We: Higher order currents from Towner and Hardy. • What is the basis and the dependence on the size of the basis? • Short-range Brueckner Correlations not included. But finite size effects included. • We hope to understand the differences. But for that we need to know their input parameters ( g(pp), g(ph),basis, …)! Amand Faessler, München, 24. November 2005
Uncorrelated and Correlated Relative N-N-Wavefunctionin the N-N-Potential Short Range Correlations Amand Faessler, München, 24. November 2005
Influence of Short Range Correlations (Parameters from Miller and Spencer, Ann. Phys 1976) Amand Faessler, München, 24. November 2005
Comparison of 2nbbHalf Lives with Shell model Results from Strassburg Amand Faessler, München, 24. November 2005
Neutrinoless Double Beta Decay and the Sensitivity to the Neutrino Massof planed Experiments Amand Faessler, München, 24. November 2005
Neutrinoless Double Beta Decay and the Sensitivity to the Neutrino Massof planed Experiments Amand Faessler, München, 24. November 2005
Summary:Accuracy of Neutrino Masses from 0nbb • Fit the g(pp) by 2nbb in front of the particle-particle NN matrixelement include exp. Error of 2nbb. • Calculate with these g(pp) for three different forces (Bonn, Nijmegen, Argonne) and three different basis sets (small about 2 shells, intermediate 3 shells and large 5 shells) the 0nbb. • Use QRPA and R-QRPA (Pauli principle) • Use: g(A) = 1.25 and 1.00 • Error of matrixelement 20 to 40 % (96Zr larger; largest errors from experim. values of T(1/2, 2nbb)). • Core overlap reduction by ~0.90 (preliminary) Amand Faessler, München, 24. November 2005
Summary:Results from 0nbb • Klapdor et al. from 0nbb Ge76 with R-QRPA (no error of theory included): 0.15 to 0.72 [eV]. • <m(n)>(0nbb Ge76, Exp. Klapdor) < 0.47 [eV] • <M(heavy n)> > 1.2 [GeV] • <M(heavy Vector B)> > 5600 [GeV] • SUSY+R-Parity: l‘(1,1,1) < 1.1*10**(-4) • Mainz-Troisk, Triton Decay: m(n) < 2.2 [eV] • Astro Physics (SDSS): Sum{ m(n) } < ~0.5 to 2 [eV] Do not take democratic averaged matrix elements !!! Amand Faessler, München, 24. November 2005
Open Problems: 1. Overlapping but slightly different Hilbert spaces in intermediate Nucleus for QRPA from intial and from final nucleus. 2. Pairing does not conserve Nucleon number. Problem at closed shells. Particle projection. Lipkin-Nogami <N>, <N2> 3. Deformed nuclei? (e.g.: 150Nd ) THE END 0+ pn-1 1+ β- 2- np-1 0+ 0+ Amand Faessler, München, 24. November 2005