neutrinoless double beta decay

18 Feb. 2005, E.J.Chun, KIAS18 Feb. 2005, E.J.Chun, KIAS Workshop for Underground Experiment and AstrWorkshop for Underground Experiment and Astroparticle Physics, Muju, 2005. 2. 16-19oparticle Physics, Muju, 2005. 2. 16-19

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Neutrinoless Double BetNeutrinoless Double Beta Decaya Decay

Eung Jin ChunEung Jin ChunKorea Institute for Advanced StudyKorea Institute for Advanced Study

APS neutrino study: physics/0411216APS neutrino study: physics/0411216 hep-ph/0412300hep-ph/0412300 Bilenky, et.al., hep-ph/0402250Bilenky, et.al., hep-ph/0402250

18 Feb. 2005, E.J.Chun, KIAS Workshop for Underground Experiment and Astroparticle Physics, Muju, 2005. 2. 16-19

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Key questions by theoristsKey questions by theorists APS neutrino study: physics/0411216APS neutrino study: physics/0411216

►Are neutrinos their own anti-particles?Are neutrinos their own anti-particles?►What is the pattern of neutrino masses?What is the pattern of neutrino masses?► Is there CP violation in the leptonic sector? Is there CP violation in the leptonic sector?

-- -- Possibly the origin of the matter-antimatter asymmetry of the universPossibly the origin of the matter-antimatter asymmetry of the universe?e?

►Are there additional neutrino species as may Are there additional neutrino species as may be hinted by the LSND experiment?be hinted by the LSND experiment?

18 Feb. 2005, E.J.Chun, KIAS Workshop for Underground Experiment and Astroparticle Physics, Muju, 2005. 2. 16-19

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Majorana(Majorana( = = cc) or Dirac() or Dirac( cc)?)?L L 0 or 0 or L= 0 L= 0

► Neutrinoless double beNeutrinoless double beta decay (0ta decay (0))

► Beta decayBeta decay

ppnn

nn pp

ppnn

nn pp

e-e-

e-e-

e-e-

mm

e-e-

18 Feb. 2005, E.J.Chun, KIAS Workshop for Underground Experiment and Astroparticle Physics, Muju, 2005. 2. 16-19

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Neutrino mass patternsNeutrino mass patterns

mm = 0.1-0.5 eV = 0.1-0.5 eV : : QQuasi-uasi-DDegenerate egenerate cosmologiccosmological massal mass – – 200 kg200 kg of isotope of isotope

mm = 0.02-0.05 eV = 0.02-0.05 eV : : IInverted-nverted-HHierarchy ierarchy oror QD with QD with NNormal-ormal-HHierarchy ierarchy atmospheric neutrino massatmospheric neutrino mass – – 1 ton1 ton

mm = 2-5 meV = 2-5 meV : QD, IH, NH : QD, IH, NH solar neutrino masssolar neutrino mass – – 100 tons100 tons

18 Feb. 2005, E.J.Chun, KIAS Workshop for Underground Experiment and Astroparticle Physics, Muju, 2005. 2. 16-19

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Tritium beta decay Tritium beta decay mmee

< 2.2 eV < 2.2 eV at Mainz & Troitsk at Mainz & Troitsk

18 Feb. 2005, E.J.Chun, KIAS Workshop for Underground Experiment and Astroparticle Physics, Muju, 2005. 2. 16-19

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Cosmolgy Cosmolgy

► Neutrino dark matter (hot)Neutrino dark matter (hot) hh22 = = ii m mii/92.5 eV/92.5 eV► Power spectrum of small scale structure Power spectrum of small scale structure ddFS FS (Gpc) (Gpc) »» 1/m 1/m (eV) (eV)

* current bound : * current bound : ii m mii < 0.2-0.6 eV < 0.2-0.6 eV

* future sensitivity : 0.14 eV (Planck)* future sensitivity : 0.14 eV (Planck)

18 Feb. 2005, E.J.Chun, KIAS Workshop for Underground Experiment and Astroparticle Physics, Muju, 2005. 2. 16-19

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( Astrophysics )( Astrophysics ) physics/0411216physics/0411216

► Detection of the GZK neutrinosDetection of the GZK neutrinos (E(E > 10 > 101515 eV), produced from the interactio eV), produced from the interactio

ns of UHECR protons with CMBRns of UHECR protons with CMBR► $10 million to enhance radio-based technol$10 million to enhance radio-based technol

ogies or develop new technologies reaching ogies or develop new technologies reaching 10 x sensitivity.10 x sensitivity.

18 Feb. 2005, E.J.Chun, KIAS Workshop for Underground Experiment and Astroparticle Physics, Muju, 2005. 2. 16-19

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( An astrophysical neutrino flux model )( An astrophysical neutrino flux model )

18 Feb. 2005, E.J.Chun, KIAS Workshop for Underground Experiment and Astroparticle Physics, Muju, 2005. 2. 16-19

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Neutrino mases and mixingNeutrino mases and mixingll = = I I U Uli li eeiii/2i/2 ii

l = e, l = e, , , and i = 1, 2, 3 and i = 1, 2, 3 three angles: three angles: ijij; three phases: ; three phases: 1,21,2, , ; ;

three masses: three masses: mmii

18 Feb. 2005, E.J.Chun, KIAS Workshop for Underground Experiment and Astroparticle Physics, Muju, 2005. 2. 16-19

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00 & & decay and oscillations decay and oscillations

APS 0APS 0 study : hep-ph/0412300 study : hep-ph/0412300

► P(P(ll -> -> kk) = ) =

sinsin2222 sin sin22[1.27[1.27mm22ijij(eV(eV22)L(km)/E(GeV)])L(km)/E(GeV)]

► decay : decay : mmee = [ = [ ii |U |Ueiei||22mmii

22]]11/2/2

►decay : decay : mm = | = |ii U Ueiei22 m mii e eiiii | |

18 Feb. 2005, E.J.Chun, KIAS Workshop for Underground Experiment and Astroparticle Physics, Muju, 2005. 2. 16-19

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Oscillation parametersOscillation parameters SK,K2K,SNO,KamLAND,CHOOZSK,K2K,SNO,KamLAND,CHOOZ

► mm222121 = 8.2 = 8.2 ££ 10 10-5-5 eV eV22

1212 = 32.3 = 32.3oo

► || m m223232| = 2.0 | = 2.0 ££ 10 10-3-3 eV eV22

sinsin22222323 > 0.94 > 0.94► sinsin22221313 < 0.11 < 0.11

QD: m0 ¼ m3,2,1NH: NH: mm22

3232 > 0 (m > 0 (m33 > m > m22 > > mm11) ) IH: IH: mm22

3232 < 0 (m < 0 (m22 > m > m11 > > mm33))

+0.6-0.5

+0.6-0.4

+2.7-2.4

18 Feb. 2005, E.J.Chun, KIAS Workshop for Underground Experiment and Astroparticle Physics, Muju, 2005. 2. 16-19

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Ranges of mRanges of m

►NH: mNH: m = |[ = |[ m m22SS]]1/21/2 s s1212

22 c c232322

+[+[ m m22AA ] ]1/21/2 s s1313

22 e e-i-i22||

► IH: mIH: m = [ = [ m m22AA]]1/21/2 c c1313

2 2

££[1-4s[1-4s121222cc1212

2 2 sinsin22((22--11)/2])/2]1/2 1/2

►QD: mQD: m=m=m00 |(c |(c121222eeii11+s+s1212

22eeii22)c)c13132 2

+s+s131322||

18 Feb. 2005, E.J.Chun, KIAS Workshop for Underground Experiment and Astroparticle Physics, Muju, 2005. 2. 16-19

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Ranges of mRanges of m

18 Feb. 2005, E.J.Chun, KIAS Workshop for Underground Experiment and Astroparticle Physics, Muju, 2005. 2. 16-19

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00 and nuclear structure and nuclear structure

► Decay rate of (A, Z) -> (A, Z+2) e+ e+ : 1/TDecay rate of (A, Z) -> (A, Z+2) e+ e+ : 1/T00

1/21/2(A,Z) = (A,Z) =

GG00(E(E00,Z) | M,Z) | M00GTGT – (g – (gVV

22/g/gAA22) M) M00

FF | |22 m m22

► Heidelberg-Moscow Heidelberg-Moscow 7676Ge experiment : Ge experiment : TT00

1/21/2 > 1.9 10 > 1.9 102525 yrs yrs !! mm < 0.55 eV < 0.55 eV

18 Feb. 2005, E.J.Chun, KIAS Workshop for Underground Experiment and Astroparticle Physics, Muju, 2005. 2. 16-19

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Nuclear structure issuesNuclear structure issues

► QQuasiparticle uasiparticle RRandom andom PPhase hase AApproximation (10%?)pproximation (10%?)► Shell ModelShell Model► Constraining with other observablesConstraining with other observables► Reducing the uncertainty (factor 2-3 presently) :Reducing the uncertainty (factor 2-3 presently) :

18 Feb. 2005, E.J.Chun, KIAS Workshop for Underground Experiment and Astroparticle Physics, Muju, 2005. 2. 16-19

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Future prospectsFuture prospects Bilenky et.al., hep-ph/0402250Bilenky et.al., hep-ph/0402250

18 Feb. 2005, E.J.Chun, KIAS Workshop for Underground Experiment and Astroparticle Physics, Muju, 2005. 2. 16-19

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(note) Beta decay : m(note) Beta decay : mee < 0.2 eV at KATRIN < 0.2 eV at KATRIN

18 Feb. 2005, E.J.Chun, KIAS Workshop for Underground Experiment and Astroparticle Physics, Muju, 2005. 2. 16-19

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ConclusionsConclusions hep-ph/0412300hep-ph/0412300