Neutrino Nuclear Responses For Double Beta Decays And Supernova Neutrinos

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1 Neutrino Nuclear Responses For Double Beta Decays And Supernova Neutrinos Hidetoshi Akimune Konan University INPC016

2 Collaborators Hidetoshi Akimune Konan University Hiro Ejiri RCNP, Osaka Dieter Frekers Muhsin Harakeh Universität Münster KVI-CART, Groningen T. Agodi INS INFN Catania N. Kalantar KVI, Groningen M. Alanssari IKP, Univ. Münster A. Lennarz IKP, Univ. Münster F. Cappuzzello IKP, Univ. Münster Y. Matsuda Tohoku CYLIC D. Carbone INS INFN Catania P. Puppe IKP, Univ. Münster M. Cavallaro INS INFN Catania P. Ries TV Darmstadt F. Diel K oln University C.Rigollet IKP, Univ. Münster C. A. Douma KVI, Groningen J. Suhonen Univ. Jyvaskyla H. Fujita RCNP Osaka A. Tamii RCNP Osaka Y. Fujita RCNP Osaka K. Heguri Konan University M. Fujiwara RCNP Osaka F. Hattori Konan University G. Gey RCNP Osaka J. Gellanki KVI, Groningen K. Hatanaka Osaka University V. Werner TV Darmstadt M. Holl IKP, Univ. Münster R. Zegars NSCL MSU A. Inoue INPC016 RCNP Osaka

3 Double beta decay (A,Z) (A,Z+) + e - + ν e (A,Z) (A,Z+) + e - νββ 0νββ M - β ( 3 He,t) β M + C 0νββ: unique process to measure the characteristics of neutrino Neutrino mass measurement via half-life measurement Requires half-life measurements beyond 10 0 yrs!!!! A ββ B

ν-nuclear responses for ββ-ν physics T 0νββ 1 = G 0ν < m ν > M 0ν ν nuclear response[m 0ν ] is needed for m ν study [1,] M 0ν = M + M Nuclear models such as QRPA, IBM include uncertain

4 ν-nuclear responses for ββ-ν physics T 0νββ 1 = G 0ν < m ν > M 0ν ν nuclear response[m 0ν ] is needed for m ν study [1,] M 0ν = M + M Nuclear models such as QRPA, IBM include uncertain renormalization of axial weak coupling in the nuclear medium (g A ) eff We need experimental (g A ) eff for [M 0ν ] for relevant states to help theoretical calculations. If (g A ) eff changes -10%, [M 0ν ] changes -40% and 3 times larger detector is needed for same statistics Experiments, ( 3 He,t) RCNP : present, (p,n) (n,p), (t, 3 He),(d, He), ( 7 Li, 7 Be),,,, µ-capture MuSIC RCNP γ-capture NewSUBARU [1] H. Ejiri, Phys. Rep. 338 (000), JPSJ 74 (005). [] J. Vergados, H. E, F. Simkovic, Rep. Prog. Phys. 75 (01). M ± = (g A ) eff M ± (QPRA) β ( 3 He,t) β M + A M - C ββ B

( 3 He,t) reaction at RCNP Osaka High energy resolution (ΔE~30 kev ) is essential to separate intermediate states in DBD nuclei, At E/u = 140 MeV, relatively large V στ and small V 0 We have good

using M ± = (g A ) eff M ± (QRPA) Next step, M oν for 0νββ To study ν-mass Exp. M ν QP g A eff M(QP) ) [5] H.Ejiri D. Frekers, N. Harakeh, H.A., et al.

5 ( 3 He,t) reaction at RCNP Osaka High energy resolution (ΔE~30 kev ) is essential to separate intermediate states in DBD nuclei, At E/u = 140 MeV, relatively large V στ and small V 0 We have good data for Gamow -Teller and Spin-Dipole state on DBD nuclei [5] So far, M ν for νββ M ν = M + (GT1 + )M (GT1 + ) real ν are in s-wave M ν are well reproduced [6]. using M ± = (g A ) eff M ± (QRPA) Next step, M oν for 0νββ To study ν-mass Exp. M ν QP g A eff M(QP) ) [5] H.Ejiri D. Frekers, N. Harakeh, H.A., et al., PRC (013), C 86, (01) C 84, (011), C 77, (008), C 74, (006), C 74, (006), C 70, (004), C68, (003), C64, (001), PRL (007), 85, 444 (000), 8, 316 (1999), PLB 706, 134 (011).394B, 3 (1997) [6] H. Ejiri. JPSJ 78 (009) 7401, 81 (91) 3301

Spin Dipole (SD) - for 0νββ 0νββ : virtual ν exchange inside nuclei q ~ 1/r = 1-0.

6 Spin Dipole (SD) - for 0νββ 0νββ : virtual ν exchange inside nuclei q ~ 1/r = fm -1, rq=l~ 1- J π = - is the major component Cross Section for ( 3 He,t) reaction σ (SD) = KF(q,ω) J SD B(SD) M(SD) = g A τ [ σ f (r)y 1 ] J i +1 We aim to experimentally provide J SD to get M(SD) from σ (SD) M(SD) = (g A ) eff M(QPRA) for strong SD states observed in DBD nuclei to help theories such as QRPA to test feasibility of ( 3 He,t) for SD B(SD) = M(SD) M 0 ν J. Suhonen Ca Positive Parity Pd Ge Zr Mo SnTe Te Se Cd Xe Xe Nd NdSm Gd - IBM QRPA Tü QRPA Jy QRPA def ISM EDF PHFB Pt Negative Parity Neutron number J. Barea et al. PRC (015) Th U

Keys for ν response are (1) τσ correlation and () g A eff in nuclear medium M m for Single - 0 + β decay Here M m =[M + M - ] 1/ M + for A(Z,N) A(Z+1,N-1) M - for A(Z-1,N+1) Phenomenological

7 Keys for ν response are (1) τσ correlation and () g A eff in nuclear medium M m for Single β decay Here M m =[M + M - ] 1/ M + for A(Z,N) A(Z+1,N-1) M - for A(Z-1,N+1) Phenomenological reduction factor k, k τσ, k NM M m (EXP) = k M m (QP) k= k τσ k NM ~ 0. M m (QRPA) = k τσ M m (QP) k τσ ~ 0.4 τσ correlation M m (EXP) = k NM M m (QRPA) k NM ~ 0.5 = g eff A n-medium Are these reductions generally valid for SD ground /excited states in DBD nuclei? [8] H. Ejiri, Proc. MEDEX 13, APS conf. series, proc. 157 (013) 40. [9] H. Ejiri, N. Soukouti, and J. Suhonen, Phys. Lett. B 79 (014) 7. M - M + g.s. (0+) g.s. (-) g.s(0+) QP QR EX

8 Level diagrams for DBD nuclei and Benchmark nuclei with known ft ββ decay nuclei ( 3 He,t) Benchmark nuclei with known lifetime 6.3 h EC 33 As β <0.0% 76 3 Ge Q β 96.0 Q EC h Se Ge d As EC 66% Q β Q EC 56.4 β 34% 0+ log ft = Se Ev 0+ > y 18 5 Te β β m I EC 6.9% Q β 118 Q EC 151 β 93.1% 0.0 d 4.18 d 14 EC 53 I Q EC Q β Xe Q β β 867 INPC Xe Te First forbidden unique transition Evaluators: (ΔJ =, Parity change)

9 74 Ge( 3 He,t) 74 Ge, 1 Sn( 3 He,t) 1 Sb, 14 Te ( 3 He,t) 14 I In May 016, we performed ( 3 He,t) experiment as benchmark for M(SD) Nuclei with large response (M m (SD)) known from β decays. Unique σ, τ, l flip transitions [σy 1 ] >> δp [σy 3 ] ΔJ=, parity change Neighbor to DBD nuclei. σ(sd) s were measured so far. 76 Ge, 18,130 Te 74 Ge and 14 Te: to see if any mass dependence of 1 Sn (semi-magic) and 14 Te with similar A and QP: to see if any nuclear structure effects and to confirm σ (SD) = KF(q,ω) J SD B(SD) J SD

10 Experiment at RCNP Osaka Univ. ( 3 He,t) reaction at 40 MeV High resolution spectrometer Grand Raiden ΔE < 50 kev θ = 0 to 5 o

In order to achieve high resolution (ΔE ~ 30 kev), very thin (less than 1 mg/cm)

11 Target Germanium and Tellurium are known as materials which are very difficult to make thin foil: Hard and fragile. In order to achieve high resolution (ΔE ~ 30 kev), very thin (less than 1 mg/cm) foil is required. Vapor deposition on thin carbon foil Carbon foil ~40 µg/cm 74Ge, 14Te ~ 50 µg/cm INPC016 INS INFN Catania ITALY

12 - 18,130 Te (ββ nuclei) and 14 Te (benchmark) show clear GT and SD states RCNP high resolution system is the unique and only opportunity dσ/dω /(5 kev mb/sr) dσ/dω /(5 kev mb/sr) C g.s (1 + ) (a) ( ) ( ) (b) ( )( ) 18 Te( 3 He,t) 18 I 18 I 130 Te( 3 He,t) 130 I 130 I Counts (0 + ) (0 + ) IAS IAS 13 C g.s (3+) 0.60 ( - ) ( ) 14 I 0.0 o < Θlab < 0.5 o 0.5 o < Θlab < 1.0 o 1.0 o < Θlab < 1.5 o This Work Preliminarily 0.0 o < Θlab < 0.5 o 0.5 o < Θlab < 1.0 o 1.0 o < Θlab < 1.5 o [5-]PRC INPC016 C 86, (01)P. Puppe, H.Ejiri, D.Frekers, H.A. et al. E x (MeV) Ex [MeV] IAS

13 76 Ge (ββ nuclei) and 74 Ge (benchmark) 10-3 yield/(5 kev msr) (1 + ) 0.10 (1 + ) 76Ge(3He,t)76As 5 E = 40 MeV g.s. ( ) 0.65 (1 + ~0.50 (1 + ), ) ( ) (1 + ) 0.68 ( (1 +, ) ) (1 + ) { 1.35 ( (1 + ) ) ( (1 + + ) ) g.s. 74As ( ) As (1 + ) E = 30 kev.537 (1+).604 (1+).940 (1 + ) 3.04 (1 + ) (1 + ) (1 + ) 4.68 (1 + ) 76 As IAS 0.0 < Θ lab < < Θ lab < < Θ lab < < Θ lab <.0.0 < Θ lab <.5 GTR SDR 10-4 yield/(5 kev msr) IAS 76 Ge (0 + ) 74 Ge (0 + ) E x [MeV] J.H. Thies, D. Frekers et.al PRC (01) Ex [MeV] Counts As 18 O g.s.. 13 C g.s (1 + ) (0.8 -,1 + ) (0.4 -,1 + ) ( ) ( ) This Work Preliminarily IAS 76 Ge: although g.s. is - log ft is not know because of low Q 74 Ge: g.s. is INPC016 E (MeV)

14 74,76 Ge( 3 He,t) 74,76 As Angular distribution 100 E x J π = g.s. = E x = 86 kev E x = 10 kev J π = As 74 As 10-1 Σ L=1 100 Σ 1 GT 10-1 L= 1 dσ/dω (A.U.) dσ/dω (A.U.) 1000 Ω [ L=3 E x J 101 π = = 0 + MeV IAS SD 1+ GT 0+ IAS dσ/dω (A.U.) DWBA calc θ cm (deg) θ cm (deg) INPC θ (deg)

15 Estimation of M(SD-) 76 As(g.s. - ) - 76 Ge(g.s. 0 + ) B(F) = N-Z = 1 B(SD) = β-decay M(SD) = As(g.s. - ) - 74 Ge(g.s. 0 + ) B(F) = N-Z = 10 B(SD) = 0.610±0.0 M(SD)= 1.75±0.04 σ SD (q,ω) = KF(q,ω) J SD B(SD ) σ IAS (q,ω) = KF(q,ω) J τ B(F) IAS: σ IAS is peaked at 0 deg. SD: σ SD is peaked at.1 deg. for ( 3 He,t) at 140 MeV/u Preliminarily Only statistical error σ SD (.1deg, 74 Ge) σ IAS (0.0deg, 74 Ge) σ SD (.1deg, 76 Ge) σ IAS (0.0deg, 76 Ge) = B(SD, 74 Ge) B(F, 74 Ge) B(SD, 76 Ge) B(F, 76 Ge) INPC016

16 Summary We will perform experiment on ( 3 He,t) reaction from nuclei with known ft values of the first forbidden beta decay. We determined M(SD-) from angular distribution of SD- states in ββ nuclei ( 74 Ge) We aim to establish a method to estimate M 0ν for 0ν double beta decay INPC016

17 X axis CER - cross sections corrected for distortions used for GT by Ejiri, Frekers, Harakeh, H.A. et al PRC Y axix M(SD) calcurated by using experimental g A from ft data in neighboring nuclei by Ejiri INPC016

18 Motivation 1. ν-nuclear responses for ββ-ν & astro-ν studies T = G [m ν M ββ ] Nuclear response= [M ββ ] for m ν study Suhonen M 0ν values depend on models (g A ) by a factor 3, equivalent to 100 in detector volume. Which is right? or all are not right??. We need experimental data to support and/or confirm theories. [1] H. Ejiri, Phys. Rep. 338 (000) 65. [] J. Vergados, H. Ejiri, F. Simkovic, Rep. Prog. Phys. 75 (01) [3] H. Ejiri, J. Phys. Soc. Jpn. 74 (005) 101. INPC016

SN ν e, ν x oscillation ν φ e n 10 8 6 4 ν e, e 1 +, ν x ν e, e 0 40 35 30 0 1 1.

19 SN ν e, ν x oscillation ν φ e n ν e, e 1 +, ν x ν e, e Spi n + and - ν µ,τ 1 +, 1 -, - 5 ν e, e INPC Spi n + and -

Neutrino Nuclear Responses for ββ ν & Charge Exchange Reactions. Hiro Ejiri RCNP Osaka & CTU Praha

Neutrino Nuclear Responses for ββ ν & Charge Exchange Reactions Hiro Ejiri RCNP Osaka & CTU Praha Nuclear responses (matrix elements) for ββ ν and charge exchange reactions H. Ejiri, Phys. Report 338 (2000)