γ 東北大サイクロにおける - Osaka University...PMT cryostat for LN2 Beam RCNP入射サイクロトロン更新で展開される新しい研究 2 February 19-20, 2006 BGO

東北大サイクロにおけるγ線核分光

東北大学サイクロトロンRIセンター東北大学大学院理学研究科

鈴木智和

February 19-20, 2006


Contents

1. Hyperball-2

• Detectors, Advantages, Disadvantages• BGO anti-Compton supressor• FERA-VME DAQ system

2. Nuclear Chirality

• Criteria for Nuclear Chirality• Lifetime Measurements in the A ∼130 region• Chiral Candidates and Possible Existance in the A ∼100 region

3. Experiments with Hyperball-2

• Spectra, Linear Polarization• Experiment Result

4. Possible experiments for nuclear chirality in RCNP

RCNP入射サイクロトロン更新で展開される新しい研究 1


Hyperball-2

• Total of 20 detectors

– Photo peak efficiency ∼4% at 1MeV∗ Eurisys Coaxial Ge + BGO (R.E. 60%, ×4)∗ ORTEC Coaxial Ge + BGO (R.E. 60%, ×10)∗ Eurisys Clover Ge + BGO

(R.E. 20%×4,125% with addback ×4)

• Advantages

– Large total photo peak efficiency (γ-γ-γ

coincidence measurement)

– Possible to use with high intensity (∼10pnA)

beam (high counting rate).

• Disadvantages

– Few angles∗ Detectors placed mostly around 90◦. (lower angular

correlation sensitivity)

– Detectors in upper and lower ring point off

center

13014 25327

BGO

clover Ge crystalsingle Ge crystal

PMT

cryostat for LN2

Beam



BGO anti-Compton suppressor

0 1000 2000 3000 4000 5000Energy (ch)

1

10

100

1000

Cou

nts

0 2000 40001

10

100

1000

0 1000 2000 3000 4000 5000Energy (ch)

1

10

100

1000

Cou

nts

0 2000 40001

10

100

1000

Ge-1 × BGO1 ∪ BGO2 ∪ BGO11 ∪ BGO12




Ge1 Ge2

Ge3Ge4

1 2 3

4

5

6

11

12

10

9 8 7

Ge

1

2

3

4

5

6

12 BGO + 1 Ge = 13 TUL IN channels

−→ 78 TUL IN channels for 6 Clovers

32 ECL IN + 16 NIM IN = 48 IN per TUL

Peak/Total BGO OFF BGO ON

Normal type ∼18% ∼32%Clover(individual) ∼10% ∼15%Clover(add-back) ∼20% ∼30%



FERA-VME Double Buffer Data Taking System

• Switching of two memory modules controled by TUL

– No dead time for data transfer from ADC/TDC to UMEM

(VME universal memory module developed by Osaka Univ.)

– For 1 event data size = 100byte– FERA ADC,TDC → UMEM 29μsec/event

∗ Conversion time of ADC 24μsec/event∗ data transfer(20Mbyte/sec) 5μsec/event

– UMEM → PC (5Mbyte/sec) 20μsec/event

ADC(AD413A)

TDC(3377)

FERA

FERA

UMEM(1)

UMEM(2)

VME PC



Nuclear Chirality

• For mass 80 region (πg9/2 ⊗ νg−19/2)

1. 1-axis: longest axis of the triaxial shape

jn; neutron-hole in a high-jn shell

2. 2-axis: shortest axis

jp; proton-particle in a high-jp shell

3. 3-axis : intermediate axis of the triaxial shape

R; core rotation

• Three perpendicular angular momentumcan be formed into two systems ofhandedness, the right-handed or the left-handed system

jn

jp

RR

jp

jn

R L

(2)

(1)

(3)(3)

(2)

(1)

I

I+2

I+1

I + I -

[O, H] = 0

O = TR (π)

H |IR〉 = εR |IR〉 , H |IL〉 = εL |IL〉O |IR〉 = |IL〉 , O |IL〉 = |IR〉

εR = εL

{|IM+〉 = 1√

2(|L〉 + |R〉)

|IM−〉 = − i√2(|L〉 − |R〉)



Criteria for Nuclear Chirality

• Nearly degenerate ΔI = 1 twin bands with the same parity

– observed in some odd-odd and odd-A nuclei in A ∼130 region(proton h11/2 particle and neutron h11/2 hole configuration)∗ 124,126,128,130,132Cs, 130,132,134La, 132,134Pr, 136Pm, 138,140Eu, 135Nd, 135Ce

– observed in some odd-odd and odd-A nuclei in A ∼100 region(proton g9/2 hole and neutron h11/2 particle configuration)∗ 107Ag, 102,103,104,105,106Rh, 100Tc

• B(E2 : I → I−2)in,out and B(M1 : I → I−2)in,out valuesare the same or similar between both bands.

– lifetime measurements are required.∗ measured in 134Pr, 132La, and 128Cs∗ GS plus plunger experiment done for 103,104Rh

(RDDS; Recoil Distance Doppler shit Method)

inout

inoutI+1 or I+2

I+1 or I+2

I

I



Lifetime measurements in the mass 130 region

8 10 12 14 16 18 20 220.0

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

B(E

2)(e

2 b2 )

Band 1

Band 2

Experiment

8 10 12 14 16 18 20 220.0

0.5

1.0

1.5

2.0

2.5

B(M

1,I

I-1)

(nm

2 ) Band 1Band 2Experiment

Lifetime measurement in Pr134

- Euroball IV + Cologne plunger device

- RDDS/DSAM

From D. Tonev et. al. Phys Rev. Lett.

96 (2006) 052501

Lifetime measurement in Cs,128

La132

- OSIRIS II (Warsaw)

- DSAM

From E. Grodner et. al. Phys Rev. Lett.

97 (2006) 172501

is best chiral cadidates!Cs128



GAMMASPHERE GSFMA169

Lifetime measurement of candidates chiralmembers in the A ∼100 region• Recoil Distance Doppler Shift Method (RDDS)

– GAMMASPHERE Ge detectors array(Total 17-rings, 110 detectors with BGO-ACS)

– Cologne univ. plunger device

• Inverse Kinematics Reaction– 11B(96Zr,xn)104,103Rh (x=3,4)– E(96Zr) = 330MeV from ATLAS accelerator at ANL– 7 distances (8,15,23,35,50,75,100 μm)

B

300

Nb

4.5mg/cm 3mg/cm

Nb

d

β=5.14% β=3.17%Zr

330MeV

(fast) (slow)

96 9311 93

µg/cm2

2 2

880 885 890 895 900 905 910 915 9200

200

400

600

800

1000

1200

1400

Energy (keV)

Co

un

ts/0

.5k

eV

8 µm

100 µm

35 µm

370 375 380 385 390 395 400 405 410

0

100

200

300

400

500

600

700

800

900

1000

Energy (keV)

Co

un

ts/0

.5k

eV

8 µm

100 µm

35 µm

(fast)

(slow)

(fast)

(slow)

From J. Timar et. al. Phys Rev C

73 (2006) 011301



Chiral Candidates and possible existence in the A ∼100 region

0.1 0.2 0.3β

0

20

40

60 In isotopes

0

20

40

60

γ

Ag isotopes

0

20

40

60 Rh isotopes

98Rh 102

Rh100Rh

104Rh

106Rh

108Rh

110Rh

114Rh112

Rh

102Ag

104Ag

106Ag

108Ag

110Ag 112

Ag

114,116Ag

102,104,110,106,108In100

In

114In

112In

116,118In

Rh102

Rh103

Rh104

Rh105

Tc100

Rh106

Ag106

Ag107

Tc101

Tc102

Ru101

Ru102

Ru103

Ru104

Pd103

Pd104

Pd105

Pd106

Pd107

Pd108

Ag104

Ag105

Ag108

Ag109

Cd106

Cd105

Cd108

Cd107

Cd110

Cd109

Cd112

Cd111

In106

In107

In108

In109

In110

In111

In112

In113

In114

Ag110

Rh107

Rh108

Rh109

Rh110

Pd102

Ag103

Cd104

In105

Pd101

Ag102

Cd103

In104

Rh100

Rh101

Tc98

Tc99

Ru99

Ru100

Ag111

Ag112

Cd113

Pd109

Pd110

Pd111

Cd114

In115

In116

Rh111

Rh112

Ag113

Ag114

Cd115

Pd112

Pd113

Ru105

Ru106

Ru107

Ru108

Ru100

Tc103

Tc104

Tc105

Tc106

Tc107

Tc108

Tc109

Tc110

Ru109

Ru110

Ru111

49

48

47

46

45

44

43

55 56 57 58 59 60 61 62 63 64 65 66 67

8 10 12 14 16Spin (I)

8 10 12 14 16Spin (I)

0

10

20

30

S(I)

[ke

V/h-

]

8 10 12 14 16Spin (I)

8 10 12 14 16Spin (I)

8 10 12 14 16Spin (I)

0

10

20

30

S(I)

[ke

V/h-

] 100Rh

102Rh

104Rh

106Rh

98Rh

98Tc 100

Tc

N=53 N=55 N=57 N=59 N=61

N=57N=55

From P. Joshi et. al. J. Phys. Nucl. Part. Phys.

31 (2005) S1895-S1898

From J. Meng et. al. Phys. Rev. C 73 (2006) 037303

0

1

2

3

4

5

Exc

itatio

n E

nerg

y [M

eV]

YrastPartner

9 10 11 12 13 14 15 16 17 18

Spin [h-]

From C. Vaman et. al. Phys. Rev. Lett.

92 (2004) 032501

Rh104

S(I)=[E(I)-E(I-2)]/2I



Nuclear Chirality in the A ∼80 region

• proton h11/2 particle and neutron h11/2 hole configuration

⇐⇒ similar mechanism

• proton g9/2 particle and neutron g9/2 hole configuration

Search for chiral doublet in the new mass region

• 79Kr (odd-A, πg29/2 ⊗ νg−1

9/2)

• 80Br (odd-odd, πg9/2 ⊗ νg−19/2)



Experiment with Hyperball-2 in CYRIC

• Course 33 at CYRIC, Tohoku University

• Reaction and target

– 70Zn(13C,4n)79Kr∗ Beam: 13C3+ @ 65MeV from 930 cyclotron∗ Target: 500μg/cm2 × 2 70% enriched 70Zn (self-supporting, stacked)

– 70Zn(13C,p2n)80Br∗ Beam: 13C3+ @ 53MeV from 930 cyclotron∗ Target: 1mg/cm2 70% enriched 70Zn (Pb backing, 10mg/cm2)

• HPGe array: Hyperball-2 for γ ray detection

• trigger: γ-γ-γ (triple coincidence)

1500

3500

5500

2500 3500 4500

3000

7000

0

0

Energy (ADC Channel)

Coun

ts /

0.4

keV

826 1025 11431154

1223 1366 1510 1639

13/2+ 17/2+ 21/2+25/2+

29/2+ 33/2+ 37/2+ 41/2+

1mg/cm with Pb backing2

1mg/cm without backing2

930Cyclotron

SW1

SW2

Hyperball-2

TR-3

TR2

TR1TR5

TR4

Hyperball-2

Cource-33Cource-33

Cource-34Cource-34

BSP33-2



Deduced Level Scheme

9/2

13/2

17/2

21/2

25/2

29/2

33/2

37/2

41/2

45/2

23/2

27/2

31/2

35/2

39/2

19/2

15/2

11/2

(23/2 )

(25/2 )

(27/2 )

(29/2 )

(21/2 )

15/2

19/2

23/2

11/2

7/2

5/21/2

9/2

13/2

17/2

21/2

25/2

29/2

(33/2 )

19/2

21/2

23/2

17/217/2

13/2

9/2

5/2

3/2

7/2

11/2

15/2

7/2

826

1025

1143

1154

1223

1366

1509

1639

1785

699

1052

1350

1654

496

1746

866

976 1094

907 987

747

453

599

623

641

726

1013

1251

811

890

356

13171073

(1509)(1083)

1701

472229

637

1615

1077

1004

1024

884

721

302147666

847

980

1011

1054

1283

(1411)

362357

1157

370

546

658284355

1014 941

853

663

401182218511

755

966

293365389

743

1675

319763683

944

Kr79

36(Band 1)

(Band 2)

(Band 3)

νg9/2

π(g9/2

)2 ⊗ νg9/2−1



γ-γ-γ spectra

0

200

400

600

800

1000

1200

200 400 600 800 1000 1200 1400 1600 1800 20000

200

400

600

800

1000

1200

1400

Gated by 811-keV & 1143-keV+ 811-keV & 826-keV

Gated by 811-keV & 1025-keV+ 811-keV & 699-keV

15

09-k

eV

13

17-k

eV

89

0-k

eV

11

43-k

eV

82

6-k

eV

10

25-k

eV

69

9-k

eV

Energy (keV)

Co

nn

ts/0

.4k

eV

9/2

13/2

17/2

21/2

25/2

29/2

33/2

37/2

41/2

45/2

23/2

27/2

31/2

35/2

39/2

19/2

15/2

11/2

(23/2 )

(25/2 )

(27/2 )

(29/2 )

(21/2 )

7/2

826

1025

1143

1154

1223

1366

1509

1639

1785

699

1052

1350

1654

496

1746

866

976 1094

907 987

747

453

599

623

641

726

1013

1251

811

890

356

13171073

(1509)

(1083)

1701

472

229

637

1615

1675

763



Relative spin-parity assignment

• Linear polarization can be extracted with cloverdetectors to infer relative spin and parity.

– Sign of P can be known without knowing sensitivity

Q(E).

P =1Q

N⊥ − N‖N⊥ + N‖

600 700 800 900Energy (keV)

0

500

1000

1500

2000

2500

3000

3500

cou

nts

/2 k

eV

HorizontalVertical

699 keV

827 keV

E

M

Target

Clover Detector

VerticalCompton Scattering

HorizintalCompton Scattering

Energy (keV)p

ola

rizati

on

x s

en

siti

vit

y (

Px

Q)

Magnetic

Electric

-0.4

-0.2

0

0.2

0.4

300 500 700 900 1100 1300

9/2

13/2

17/2

21/2

25/2

29/2

33/2

23/2

27/2

31/2

19/2

15/2

11/2

(23/2 )

(25/2 )

(27/2 )

(29/2 )

(21/2 )

7/2

826

1025

1143

1154

1223

1366

699

1052

1350

1654

866

976 1094

907 987

747

453

599

623

641

726

1013

811

890

356

13171073

(1509)

(1083)

1701

472

229

637

1615

1675

763

(Band 2)

(Band 3)

(Band 1)



Discussion of result:79KrE

-0.0

231*I(

I+1)

[MeV

]E

xcit

ati

on E

nerg

y [

MeV

]S

(I)=

[E(I

)-E

(I-2

)]/2

I [k

eV

/h]

Spin [h]

4 6 8 10 12 14 16 18 200

10

20

30

40

50

60

0

2

4

6

8

10

-0.5

0

0.5

1

1.5 Band 1

Band 2

Band 1

Band 2

Band 1

Band 2

Band 3

(a)

(b)

(c)

I 27/2 29/2 31/2 33/2

E(I)P − E(I)Y in keV 811 1247 1079 1532

• If two bands are chiral partners...

– Nearly degenerate between two bands.

– Single particle states should be the same

– S(I) = [E(I) − E(I − 2)]/2I should be

smoothly varying.

The Current Result shows

that the side band structures

are of non chiral.



80Br; 70Zn(13C,p2n)@54MeV

Preliminary

200 400 600 800 1000 1200

90 166 244 446 524 668 859 972 1350Gates 524keV

Gates 166keV

3000

7000

11000

1500

3500

5500

Cou

nts/

1kev

Energy (keV)

1 2 5

5 67

8

9

10

11

10

6

7

9

7

9

12

244244

9090166166

524

972

446

270270

668

859

293

393

1076

355

823

1350



Possible experiments in RCNP

Rh102

Rh103

Rh104

Rh105

Tc100

Rh106

Ag106

Ag107

Tc101

Tc102

Ru101

Ru102

Ru103

Ru104

Pd103

Pd104

Pd105

Pd106

Pd107

Pd108

Ag104

Ag105

Ag108

Ag109

Cd106

Cd105

Cd108

Cd107

Cd110

Cd109

Cd112

Cd111

In106

In107

In108

In109

In110

In111

In112

In113

In114

Ag110

Rh107

Rh108

Rh109

Rh110

Pd102

Ag103

Cd104

In105

Pd101

Ag102

Cd103

In104

Rh100

Rh101

Tc98

Tc99

Ru99

Ru100

Ag111

Ag112

Cd113

Pd109

Pd110

Pd111

Cd114

In115

In116

Rh111

Rh112

Ag113

Ag114

Cd115

Pd112

Pd113

Ru105

Ru106

Ru107

Ru108

Ru100

Tc103

Tc104

Tc105

Tc106

Tc107

Tc108

Tc109

Tc110

Ru109

Ru110

Ru111

49

48

47

46

45

44

43

55 56 57 58 59 60 61 62 63 64 65 66 67

1. RCNP can provide various heavy ion beam.

2. The germanium detectors array will be installedin EN cource.• 15 detectors

⇐⇒ γ-γ-γ coincidence• 4 angles

⇐⇒ determine transition multipolarity with angulardistribution (DCO ratio).

• The segmented detector is placed 90◦.⇐⇒ determine electric or magnetic transition withleniar polarization.

• Lifetime measurement with DSAM method for higherspin states.

• 112In

– 110Cd(α,pn). . . M. Eibert et.al. J. Phys. G: Nucl.

Phys. 2 (1976) L203

– 96Zr(22Ne,p5n)

– 70Zn(48Ca,p5n)

• 108Ag (109Ag,110Ag)

– 100Mo(11B,3n). . . F.R. Espinoza-Quinones et. al.

Phys. Rev. C 52 (1995)

– 96Zr(15N,3n)

– 96Zr(18O,p5n)

Ebeam ∼4MeV/u



Summary

1. Hyperball-2

2. Nuclear Chirality

• Criteria for Nuclear Chirality• Lifetime Measurements• Chiral Candidates and Possible Existance in the A ∼100 region

3. Experiments with Hyperball-2

• γ-γ-γ coincidence, Linear Polarization• The observed side band structures in 79Kr are of non chiral.

4. 112In is best idea for Chiral doublet search in RCNP.



Nuclear Chart in the A ∼100 region

Rh102

Rh103

Rh104

Rh105

Tc100

Rh106

Ag106

Ag107

Tc101

Tc102

Ru101

Ru102

Ru103

Ru104

Pd103

Pd104

Pd105

Pd106

Pd107

Pd108

Ag104

Ag105

Ag108

Ag109

Cd106

Cd105

Cd108

Cd107

Cd110

Cd109

Cd112

Cd111

In106

In107

In108

In109

In110

In111

In112

In113

In114

Ag110

Rh107

Rh108

Rh109

Rh110

Pd102

Ag103

Cd104

In105

Pd101

Ag102

Cd103

In104

Rh100

Rh101

Tc98

Tc99

Ru99

Ru100

Ag111

Ag112

Cd113

Pd109

Pd110

Pd111

Cd114

In115

In116

Rh111

Rh112

Ag113

Ag114

Cd115

Pd112

Pd113

Ru105

Ru106

Ru107

Ru108

Ru100

Tc103

Tc104

Tc105

Tc106

Tc107

Tc108

Tc109

Tc110

Ru109

Ru110

Ru111

49

48

47

46

45

44

43

55 56 57 58 59 60 61 62 63 64 65 66 67

Rh99

Tc97

Ru98

Pd100

Ag101

Cd102

In103

Pd99

Ag100

Cd101

In102

Pd98

Ag99

Cd100

In101

Rh97

Rh98

Tc95

Tc96

Ru96

Ru97

Rh96

Tc94

Ru95

Pd97

Ag98

Cd99

In100

Pd96

Ag97

Cd98

In99

Pd95

Ag96

Cd97

In98

Rh94

Rh95

Tc92

Tc93

Ru93

Ru94

Mo100

Mo101

Mo102

Mo98

Mo99

Mo103

Mo104

Mo105

Mo106

Mo107

Mo108

Mo109

Mo91

Mo97

Mo95

Mo96

Mo94

Mo92

Mo93

Nb100

Nb101

Nb102

Nb98

Nb99

Nb103

Nb104

Nb105

Nb106

Nb107

Nb108

Nb97

Nb95

Nb96

Nb94

Nb92

Nb93

Nb90

Nb91

Zr100

Zr101

Zr102

Zr98

Zr99

Zr103

Zr104

Zr105

Zr106

Zr97

Zr95

Zr96

Zr94

Zr93

Zr107

Zr91

Zr92

Zr90

Zr89

Y100

Y101

Y102

Y103

Y104

Y105

Y106

Y98

Y99

Y97

Y96

Y94

Y95

Y93

Y92

Y90

Y91

Y89

Y88

Sr102

Sr103

Sr104

Sr105

Sr100

Sr101

Sr99

Sr98

Sr97

Sr95

Sr94

Sr96

Sr93

Sr92

Sr91

Sr89

Sr88

Sr90

Sr87

Rb91

Rb90

Rb88

Rb89

Kr90

Kr89

Kr87

Kr88

Rb87

Kr86

Rb86

Kr85

Rb92

Kr91

Rb93

Kr92

Rb94

Kr93

Rb95

Kr94

Rb96

Kr95

Rb97

Kr96

Rb98

Kr97

Rb99

Kr98

Kr99

Rb103

Rb104

Kr102

Kr103

Rb101

Rb102

Kr100

Kr101

Rb100

Br87

Br86

Br85

Br90

Br89

Br88

Br91

Br92

Br93

Br94

Br95

Br96

Br97

Br98

Br99

Br84

Kr101

Kr100

Kr102

4747 4848 4949 5050 5151 5252 5353 5454

42

41

40

39

38

37

36

35

Pd94

Ag95

Cd96

In97

Pd93

Ag94

Cd95

In96

Rh92

Rh93

Tc90

Tc91

Ru91

Ru92

Mo89

Mo90

Nb88

Nb89

Zr88

Zr87

Y87

Y86

Sr86

Sr85

Rb85

Kr84

Rb84

Kr83

Br83

Br82


Documents

γ 東北大サイクロにおける - Osaka University...PMT cryostat for LN2 Beam RCNP入射サイクロトロン更新で展開される新しい研究 2 February 19-20, 2006 BGO