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ACFI-FRIB M. Horoi CMU 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-FRIBM. Horoi CMU Double-beta decay and BSM physics: shell model nuclear matrix elements for competing mechanisms Mihai Horoi Department of Physics,

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ACFI-FRIB M. Horoi CMU

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

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

ACFI-FRIB M. Horoi CMU

Adapted from Avignone, Elliot, Engel, Rev. Mod. Phys. 80, 481 (2008) -> RMP08

A.S. Barabash, PRC 81 (2010)

2-neutrino double beta decay

neutrinoless double beta decay

Neutrino Masses

ACFI-FRIB M. Horoi CMU

- Tritium decay:

- Cosmology: CMB power spectrum, BAO, etc,

Two neutrino mass hierarchies

Neutrino bb effective mass

ACFI-FRIB M. Horoi CMU

Cosmology constraint

76Ge Klapdor claim 2006

The Minimal Standard Model

ACFI-FRIB M. Horoi CMU

?

M. Horoi CMU

Too Small Yukawa Couplings?

ACFI-FRIB

arXiv:1406.5503Standard Model fermion masses

arXiv:0710.4947v3

The origin of Majorana neutrino masses

ACFI-FRIB M. Horoi CMU

Type I see-saw

- SU2eimi term dominates in

most cases

- TeV collider Majorana tests not relevant

arXiv:0710.4947v3

The origin of Majorana neutrino masses

ACFI-FRIB M. Horoi CMU

See-saw mechanisms

Left-Right Symmetric model

WR search at CMS arXiv:1407.3683

Majorana neutrino masses

ACFI-FRIB M. Horoi CMU

Low-energy contributions to 0vbb decay

ACFI-FRIB M. Horoi CMU

Low-energy effective Hamiltonian

Contributions to 0vbb decay: no neutrinos

ACFI-FRIB M. Horoi CMU

See-saw type III

GUT/SUSY R-parity violation

Squark exchangeGluino exchange

Hadronization /w R-parity v.

The Black Box Theorem

ACFI-FRIB M. Horoi CMU

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!

DBD signals from different mechanisms

ACFI-FRIB M. Horoi CMU

arXiv:1005.1241

2 0b n rhc(h)

The 0vDBD half-life

ACFI-FRIB M. Horoi CMU

PRD 83, 113003 (2011)

Two Non-Interfering Mechanisms

ACFI-FRIB M. Horoi CMU

Assume T1/2(76Ge)=22.3x1024 y

M. Horoi CMU

Is there a more general description?

ACFI-FRIB

Long-range terms: (a) - (c ) Short-range terms: (d)

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

ACFI-FRIB M. Horoi CMU

2v Double Beta Decay (DBD) of 48Ca

Ikeda satisfied in pf !

The choice of valence space is important!

Horoi, Stoica, Brown,

PRC 75, 034303 (2007)

ISR 48Ca 48Ti

pf 24.0 12.0

f7 p3 10.3 5.2

ACFI-FRIB M. Horoi CMU

Double Beta Decay NME for 48Ca

M. Horoi, PRC 87, 014320 (2013)

Closure Approximation and Beyond in Shell Model

ACFI-FRIB M. Horoi CMU

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)

M. Horoi CMU

New Approach to calculate NME: New Tests of Nuclear Structure

ACFI-FRIB

Brown, Horoi, Senkov

arXiv:1409.7364,

ACFI-FRIB M. Horoi CMU

136Xe bb Experimental ResultsPublication Experiment T2n

1/2 T0n1/2(lim) T0n

1/2(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 EXO-200 >1.1x1025 y 1.9x1025 y

PRC 85, 045504 KamLAND-Zen (2.38 0.02 0.14)x1021 y

EXO-200

arXiv:1402.6956, Nature 510, 229

ACFI-FRIB M. Horoi CMU

136Xe 2nbb Results

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

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

New effective interaction,

0h11/2

2s5/2

1d3/2

1d5/2

0g7/2

0h9/2

0g9/2

np - nh

n (0+) n (1+) M(2v)

0 0 0.062

0 1 0.091

1 1 0.037

1 2 0.020

M. Horoi CMUACFI-FRIB

S. Vigdor talk at LRP Town Meeting, Chicago, Sep 28-29, 2014

M. Horoi CMU

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. 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

Take-Away Points

ACFI-FRIB M. Horoi CMU

Black box theorem (all flavors + oscillations)

Observation of 0 nbb will signal New Physics Beyond the Standard Model.

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 PointsAlternative 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

76Ge

Take-Away PointsAccurate 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.

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

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 0bb 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.

M. Horoi CMU

Effective Field Theory for BSM

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V. Cirigliano talk at LPR Town Meeting, Chicago, Sep 28-29, 2014

M. Horoi CMU

Effective Field Theory for BSM

ACFI-FRIB

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)

M. Horoi CMU

Shell Model GT Quenching

core polarization: Phys.Rep. 261, 125 (1995)

ACFI-FRIB

empty

valence

frozen core

J. Menendez, D. Gazit and A. Schwenk, arXiV:1103.3622, PRL 107

The Minimal Standard Model

ACFI-FRIB M. Horoi CMU

?

The effect of larger model spaces for 48Ca

ACFI-FRIB M. Horoi CMU

M(0v) SDPFU SDPFMUP

0 0.941 0.623

0+2 1.182 (26%) 1.004 (61%)

SDPFU: PRC 79, 014310 (2009)

SDPFMUP: PRC 86, 051301(R) (2012)

arXiv:1308.3815, PRC 89, 045502 (2014)

M(0v)

0 / GXPF1A 0.733

0 +2nd ord./GXPF1A 1.301 (77%)

PRC 87, 064315 (2013)

Other Shell Model Results

ACFI-FRIB M. Horoi CMU

0g7/2 1d5/2 1d3/2 2s5/2 0h11/2 valence space

M. Horoi CMUACFI-FRIB

S. Vigdor talk at LPR Town Meeting, Chicago, Sep 28-29, 2014

The Black Box Theorem

ACFI-FRIB M. Horoi CMU

J. Schechter and J.W.F Valle, PRD 25, 2951 (1982)

E. Takasugi, PLB 149, 372 (1984)

J.F. Nieves, PLB 145, 375 (1984)

However:

M. Duerr et al, JHEP 06 (2011) 91

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!

M. Horoi CMUACFI-FRIB

Neutrino Oscillations

ACFI-FRIB M. Horoi CMU

NHIH

Low-energy contributions to 0vbb decay

ACFI-FRIB M. Horoi CMU

Low-energy effective Hamiltonian

Some mechanisms tested at LHC

ACFI-FRIB M. Horoi CMU

PRD 86, 055006 (2012)

arXiv:1307.4849

Left-right symmetric model

Some mechanisms tested at LHC

ACFI-FRIB M. Horoi CMU

Recent CMS results a 2.8s effect arXiv:1407.3683

Broken D-parity left-right symmetric model: arXiv:1409.2820

Neutrino Oscillations

ACFI-FRIB M. Horoi CMU

Consequences of Majorana Neutrinos

ACFI-FRIB M. Horoi CMU

- 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

Fermion masses in and beyond the Standard Model

ACFI-FRIB M. Horoi CMU

Standard Model neutrino (m=0)

Beyond Standard Model Dirac neutrino (m>0)

Beyond Standard Model Majorana neutrino (m>0)

Standard Model Dirac fermions (m>0)

Standard Model photon (m=0)

Matrix Elements: Light Neutrinos

ACFI-FRIB M. Horoi CMU

PRD 83, 113003 (2011)

PRL 109, 042501 (2012)

NPA 818, 139 (2009)

Present Interacting Shell-Model

Matrix Elements: Heavy Neutrinos

ACFI-FRIB M. Horoi CMU

PRL 109, 042501 (2012)

PRD 83, 113003 (2011)

Present Interacting Shell-Model

Fermions masses in the Standard Model

ACFI-FRIB M. Horoi CMU

Standard Model neutrino (m=0)

Extended Standard Model Dirac neutrino (m>0)

Beyond Standard Model Majorana neutrino (m>0)

Standard Model Dirac fermions (m>0)

Standard Model photon (m=0)

Beyond Closure in Shell Model

ACFI-FRIB M. Horoi CMU

- 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

Challenge: there are about 100,000 Jk states in the sum for 48Ca !!!

Senkov & Horoi, PRC 88, 064312 (2013)

ACFI-FRIB M. Horoi CMU

76Ge

DBD signals from different mechanisms

ACFI-FRIB M. Horoi CMU