Double-beta decay and BSM physics: shell model nuclear matrix elements for competing mechanisms Mihai Horoi Department of Physics, Central Michigan University, Mount Pleasant, Michigan 48859, USA Support from NSF grant PHY-1404442 and DOE/SciDAC grants DE-SC0008529/SC0008641 is acknowledged ACFI-FRIB M. Horoi CMU

Overview Neutrino physics within and beyond the Standard Model (BSM) DBD mechanisms: light Majorana neutrino exchange, right-handed currents, heavy neutrinos, SUSY R-parity violation,… 48Ca: 2v and 0v shell-model matrix elements Beyond closure approximation 76Ge, 82Se, 130Te, and 136Xe results ACFI-FRIB M. Horoi CMU

Classical Double Beta Decay Problem A.S. Barabash, PRC 81 (2010) 2-neutrino double beta decay neutrinoless double beta decay Adapted from Avignone, Elliot, Engel, Rev. Mod. Phys. 80, 481 (2008) -> RMP08 ACFI-FRIB M. Horoi CMU

Neutrino Masses Tritium decay: Cosmology: CMB power spectrum, BAO, etc, Two neutrino mass hierarchies ACFI-FRIB M. Horoi CMU

Neutrino bb effective mass Cosmology constraint 76Ge Klapdor claim 2006 ACFI-FRIB M. Horoi CMU

The Minimal Standard Model ? ACFI-FRIB M. Horoi CMU

Too Small Yukawa Couplings? arXiv:1406.5503 Standard Model fermion masses ACFI-FRIB M. Horoi CMU

The origin of Majorana neutrino masses Type I see-saw arXiv:0710.4947v3 SU2eimi term dominates in most cases TeV collider Majorana tests not relevant ACFI-FRIB M. Horoi CMU

The origin of Majorana neutrino masses See-saw mechanisms Left-Right Symmetric model arXiv:0710.4947v3 WR search at CMS arXiv:1407.3683 ACFI-FRIB M. Horoi CMU

Majorana neutrino masses ACFI-FRIB M. Horoi CMU

Low-energy contributions to 0vbb decay Low-energy effective Hamiltonian ACFI-FRIB M. Horoi CMU

Contributions to 0vbb decay: no neutrinos See-saw type III GUT/SUSY R-parity violation Squark exchange Gluino exchange Hadronization /w R-parity v. ACFI-FRIB M. Horoi CMU

The Black Box Theorem J. Schechter and J.W.F Valle, PRD 25, 2951 (1982) E. Takasugi, PLB 149, 372 (1984) J.F. Nieves, PLB 145, 375 (1984) M. Hirsch, S. Kovalenko, I. Schmidt, PLB 646, 106 (2006) 0nbb observed  at some level (i) Neutrinos are Majorana fermions. (ii) Lepton number conservation is violated by 2 units Regardless of the dominant 0nbb mechanism! ACFI-FRIB M. Horoi CMU

DBD signals from different mechanisms arXiv:1005.1241 2b0n rhc(h) ACFI-FRIB M. Horoi CMU

The 0vDBD half-life PRD 83, 113003 (2011) ACFI-FRIB M. Horoi CMU

Two Non-Interfering Mechanisms Assume T1/2(76Ge)=22.3x1024 y ACFI-FRIB M. Horoi CMU

Is there a more general description? Long-range terms: (a) - (c ) Short-range terms: (d) ACFI-FRIB M. Horoi CMU

Summary of 0vDBD mechanisms The mass mechanism (a.k.a. light-neutrino exchange) is likely, and the simplest BSM scenario. Low mass sterile neutrino would complicate analysis Right-handed heavy-neutrino exchange is possible, and requires knowledge of half-lives for more isotopes. h- and l- mechanisms are possible, but could be ruled in/out by energy and angular distributions. Left-right symmetric model may be also (un)validated at LHC/colliders. SUSY/R-parity, KK, GUT, etc, scenarios need to be checked, but validated by other means. ACFI-FRIB M. Horoi CMU

2v Double Beta Decay (DBD) of 48Ca The choice of valence space is important! ISR 48Ca 48Ti pf 24.0 12.0 f7 p3 10.3 5.2 Ikeda satisfied in pf ! Horoi, Stoica, Brown, PRC 75, 034303 (2007) ACFI-FRIB M. Horoi CMU

Double Beta Decay NME for 48Ca M. Horoi, PRC 87, 014320 (2013) ACFI-FRIB M. Horoi CMU

Closure Approximation and Beyond in Shell Model Challenge: there are about 100,000 Jk states in the sum for 48Ca Much more intermediate states for heavier nuclei, such as 76Ge!!! No-closure may need states out of the model space (not considered). Minimal model spaces 82Se : 10M states 130Te : 22M states 76Ge : 150M states ACFI-FRIB M. Horoi CMU

82Se: PRC 89, 054304 (2014) ACFI-FRIB M. Horoi CMU

New Approach to calculate NME: New Tests of Nuclear Structure Brown, Horoi, Senkov arXiv:1409.7364, ACFI-FRIB M. Horoi CMU

136Xe bb Experimental Results Publication Experiment T2n1/2 T0n1/2(lim) T0n1/2(Sens) PRL 110, 062502 KamLAND-Zen > 1.9x1025 y 1.1x1025 y PRC 89, 015502 EXO-200 (2.11 0.04 0.21)x1021 y Nature 510, 229 >1.1x1025 y 1.9x1025 y PRC 85, 045504 (2.38 0.02 0.14)x1021 y EXO-200 arXiv:1402.6956, Nature 510, 229 ACFI-FRIB M. Horoi CMU

136Xe 2nbb Results np - nh 0g7/2 1d5/2 1d3/2 2s5/2 0h11/2 model space New effective interaction, 0h11/2 2s5/2 1d3/2 1d5/2 0g7/2 0h9/2 0g9/2 0h11/2 2s5/2 1d3/2 1d5/2 0g7/2 0h9/2 0g9/2 0g7/2 1d5/2 1d3/2 2s5/2 0h11/2 model space 0h11/2 2s5/2 1d3/2 1d5/2 0g7/2 0h9/2 0g9/2 0h11/2 2s5/2 1d3/2 1d5/2 0g7/2 0h9/2 0g9/2 0g9/2 0g7/21d5/2 1d3/2 2s5/2 0h11/2 0h9/2 n (0+) n (1+) M(2v) 0.062 1 0.091 0.037 2 0.020 np - nh ACFI-FRIB M. Horoi CMU

S. Vigdor talk at LRP Town Meeting, Chicago, Sep 28-29, 2014 ACFI-FRIB M. Horoi CMU

IBA-2 J. Barea, J. Kotila, and F. Iachello, Phys. Rev IBA-2 J. Barea, J. Kotila, and F. Iachello, Phys. Rev. C 87, 014315 (2013). QRPA-En M. T. Mustonen and J. Engel, Phys. Rev. C 87, 064302 (2013). QRPA-Jy J. Suhonen, O. Civitarese, Phys. NPA 847 207–232 (2010). QRPA-Tu A. Faessler, M. Gonzalez, S. Kovalenko, and F. Simkovic, arXiv:1408.6077 ISM-Men J. Menéndez, A. Poves, E. Caurier, F. Nowacki, NPA 818 139–151 (2009). SM M. Horoi et. al. PRC 88, 064312 (2013), PRC 89, 045502 (2014), PRC 90, PRC 89, 054304 (2014), in preparation, PRL 110, 222502 (2013). ACFI-FRIB M. Horoi CMU

IBA-2 J. Barea, J. Kotila, and F. Iachello, Phys. Rev IBA-2 J. Barea, J. Kotila, and F. Iachello, Phys. Rev. C 87, 014315 (2013). QRPA-Tu A. Faessler, M. Gonzalez, S. Kovalenko, and F. Simkovic, arXiv:1408.6077 SM M. Horoi et. al. PRC 88, 064312 (2013), PRC 90, PRC 89, 054304 (2014), in preparation, PRL 110, 222502 (2013). ACFI-FRIB M. Horoi CMU

Take-Away Points Observation of 0nbb will signal New Physics Beyond the Standard Model. Black box theorem (all flavors + oscillations) 0nbb observed  at some level (i) Neutrinos are Majorana fermions. (ii) Lepton number conservation is violated by 2 units Regardless of the dominant 0nbb mechanism! ACFI-FRIB M. Horoi CMU

Take-Away Points The analysis and guidance of the experimental efforts need accurate Nuclear Matrix Elements. ACFI-FRIB M. Horoi CMU

Take-Away Points Extracting information about Majorana CP-violation phases may require the mass hierarchy from LBNE, cosmology, etc, but also accurate Nuclear Matrix Elements. ACFI-FRIB M. Horoi CMU

Take-Away Points Alternative mechanisms to 0nbb need to be carefully tested: many isotopes, energy and angular correlations. These analyses also require accurate Nuclear Matrix Elements. SuperNEMO; 82Se ACFI-FRIB M. Horoi CMU

Take-Away Points Accurate shell model NME for different decay mechanisms were recently calculated. The method provides optimal closure energies for the mass mechanism. Decomposition of the matrix elements can be used for selective quenching of classes of states, and for testing nuclear structure. 76Ge ACFI-FRIB M. Horoi CMU

Experimental info needed ACFI-FRIB M. Horoi CMU

Collaborators: Alex Brown, NSCL@MSU Roman Senkov, CMU and CUNY Andrei Neacsu, CMU Jonathan Engel, UNC Jason Holt, TRIUMF ACFI-FRIB M. Horoi CMU

Summary and Outlook Observation of neutrinoless double beta decay would signal physics beyond the Standard Model: massive Majorana neutrinos, right-handed currents, SUSY LNV, etc 48Ca and 136Xe cases suggest that 2 double-beta decay can be described reasonably within the shell model with standard quenching, provided that all spin-orbit partners are included. Higher order effects for 0 NME included: range 1.0 – 1.4 Reliable 0bb nuclear matrix elements could be used to identify the dominant mechanism if energy/angular correlations and data for several isotopes become available. The effects of the quenching and the missing spin-orbit partners are important (see the 136Xe case), and they need to be further investigated for 76Ge, 82Se and 130Te. ACFI-FRIB M. Horoi CMU

Effective Field Theory for BSM V. Cirigliano talk at LPR Town Meeting, Chicago, Sep 28-29, 2014 ACFI-FRIB M. Horoi CMU

Effective Field Theory for BSM M. Hirsch talk at NEUTRINO 2014 ACFI-FRIB M. Horoi CMU

Comparisons of M0n 0nbb Results From T. Rodriguez, G. Martinez-Pinedo, Phys. Rev. Lett. 105, 252503 (2010) Present Shell Model results: Phys. Rev. Lett. 110, 222502 (2013) PRC 89, 045502 & 88, 064312 (2013) PRC 89, 054304 (2014), submitted (MS) ACFI-FRIB M. Horoi CMU

Shell Model GT Quenching empty valence frozen core core polarization: Phys.Rep. 261, 125 (1995) J. Menendez, D. Gazit and A. Schwenk, arXiV:1103.3622, PRL 107 ACFI-FRIB M. Horoi CMU

The Minimal Standard Model ? ACFI-FRIB M. Horoi CMU

The effect of larger model spaces for 48Ca M(0v) SDPFU SDPFMUP 0.941 0.623 0+2 1.182 (26%) 1.004 (61%) M(0v) 0 / GXPF1A 0.733 0 +2nd ord./GXPF1A 1.301 (77%) arXiv:1308.3815, PRC 89, 045502 (2014) SDPFU: PRC 79, 014310 (2009) PRC 87, 064315 (2013) SDPFMUP: PRC 86, 051301(R) (2012) ACFI-FRIB M. Horoi CMU

Other Shell Model Results 0g7/2 1d5/2 1d3/2 2s5/2 0h11/2 valence space ACFI-FRIB M. Horoi CMU

S. Vigdor talk at LPR Town Meeting, Chicago, Sep 28-29, 2014 ACFI-FRIB M. Horoi CMU

The Black Box Theorem J. Schechter and J.W.F Valle, PRD 25, 2951 (1982) E. Takasugi, PLB 149, 372 (1984) J.F. Nieves, PLB 145, 375 (1984) M. Hirsch, S. Kovalenko, I. Schmidt, PLB 646, 106 (2006) However: M. Duerr et al, JHEP 06 (2011) 91 0nbb observed  at some level (i) Neutrinos are Majorana fermions. (ii) Lepton number conservation is violated by 2 units Regardless of the dominant 0nbb mechanism! ACFI-FRIB M. Horoi CMU

ACFI-FRIB M. Horoi CMU

Neutrino Oscillations NH IH ACFI-FRIB M. Horoi CMU

Low-energy contributions to 0vbb decay Low-energy effective Hamiltonian ACFI-FRIB M. Horoi CMU

Some mechanisms tested at LHC PRD 86, 055006 (2012) Left-right symmetric model arXiv:1307.4849 ACFI-FRIB M. Horoi CMU

Some mechanisms tested at LHC Broken D-parity left-right symmetric model: arXiv:1409.2820 Recent CMS results a 2.8s effect arXiv:1407.3683 ACFI-FRIB M. Horoi CMU

Neutrino Oscillations ACFI-FRIB M. Horoi CMU

Consequences of Majorana Neutrinos - Leptogenesis (DL=2) => (SM sphalerons) => Baryogenesis - Exotic (DL=2) decays: - Larger magnetic moments => Larger decay rates of heavy neutrino - Different neutrino contribution to Supernovae explosion mechanism => different signals measured on Earth detectors ACFI-FRIB M. Horoi CMU

Fermion masses in and beyond the Standard Model Standard Model photon (m=0) Standard Model Dirac fermions (m>0) Standard Model neutrino (m=0) Beyond Standard Model Dirac neutrino (m>0) Beyond Standard Model Majorana neutrino (m>0) ACFI-FRIB M. Horoi CMU

Matrix Elements: Light Neutrinos Present Interacting Shell-Model PRL 109, 042501 (2012) PRD 83, 113003 (2011) NPA 818, 139 (2009) ACFI-FRIB M. Horoi CMU

Matrix Elements: Heavy Neutrinos Present Interacting Shell-Model PRL 109, 042501 (2012) PRD 83, 113003 (2011) ACFI-FRIB M. Horoi CMU

Fermions masses in the Standard Model Standard Model photon (m=0) Standard Model Dirac fermions (m>0) Standard Model neutrino (m=0) Extended Standard Model Dirac neutrino (m>0) Beyond Standard Model Majorana neutrino (m>0) ACFI-FRIB M. Horoi CMU

Beyond Closure in Shell Model Challenge: there are about 100,000 Jk states in the sum for 48Ca !!! Senkov & Horoi, PRC 88, 064312 (2013) About 300 intermediate states for each spin are (more than) enough GT dominates, and exhibits the largest change A 8-12% increase from closure was found ACFI-FRIB M. Horoi CMU

76Ge ACFI-FRIB M. Horoi CMU

DBD signals from different mechanisms ACFI-FRIB M. Horoi CMU