Search for Tetraneutron in the He(π Reaction...Li modi#ed NN interaction changes energies of other nuclides, including di-neutron 0+ 4n i n difi d S0 inclusion of extra 3N or 4N interaction

4He(π−,π+)反応によるテトラ中性子核の探索計画

Search for Tetraneutron in the 4He(π−,π+) Reaction

Hiroyuki Fujioka (Kyoto Univ.)


today’s talk based on … 2

Letter of Intent for J-PARC 50GeV Synchrotron

Search for tetraneutron by pion double charge exchange reaction on 4He

H. Fujioka,∗ S. Kanatsuki, T. Nagae, and T. NanamuraDepartment of Physics, Kyoto University

T. Fukuda and T. HaradaOsaka Electro-Communication University

E. Hiyama, K. Itahashi,† and T. NishiRIKEN Nishina Center(Dated: June 27, 2016)

Candidates of a tetraneutron resonance state, composed of four neutrons, have been observed ina heavy-ion double charge exchange reaction at RIBF. We would like to investigate this exotic stateby a pion double charge exchange reaction at the High-Intensity High-Resolution beamline in anextended Hadron Experimental Facility, which is currently in a planning stage.

nu ,d the (π− π+) r

http://j-parc.jp/researcher/Hadron/en/Proposal_e.html


motivated by … 3

Candidate Resonant Tetraneutron State Populated by the 4Heð8He;8BeÞ Reaction

K. Kisamori,1,2 S. Shimoura,1 H. Miya,1,2 S. Michimasa,1 S. Ota,1 M. Assie,3 H. Baba,2 T. Baba,4 D. Beaumel,2,3

M. Dozono,2 T. Fujii,1,2 N. Fukuda,2 S. Go,1,2 F. Hammache,3 E. Ideguchi,5 N. Inabe,2 M. Itoh,6 D. Kameda,2 S. Kawase,1

T. Kawabata,4 M. Kobayashi,1 Y. Kondo,7,2 T. Kubo,2 Y. Kubota,1,2 M. Kurata-Nishimura,2 C. S. Lee,1,2 Y. Maeda,8

H. Matsubara,12 K. Miki,5 T. Nishi,9,2 S. Noji,10 S. Sakaguchi,11,2 H. Sakai,2 Y. Sasamoto,1 M. Sasano,2 H. Sato,2

Y. Shimizu,2 A. Stolz,10 H. Suzuki,2 M. Takaki,1 H. Takeda,2 S. Takeuchi,2 A. Tamii,5 L. Tang,1 H. Tokieda,1

M. Tsumura,4 T. Uesaka,2 K. Yako,1 Y. Yanagisawa,2 R. Yokoyama,1 and K. Yoshida21

2

PRL 116, 052501 (2016)Selected for a Viewpoint in Physics

PHY S I CA L R EV I EW LE T T ER Sweek ending

5 FEBRUARY 2016


contents

1. What is “tetraneutron”?

2. Historical overview

3. Recent observation at RIBF

4. pion DCX (=double charge exchange) reaction

5. experimental plan at J-PARC

4


multi-neutron system or “Neutronium”

❖ 1n (neutron)

❖ 2n (di-neutron) unbound by ≈ 70 keV ; ann ~ −18fm

❖ 3n (tri-neutron) : hypothetical

❖ 4n (tetra-neutron) : hypothetical

5https://en.wikipedia.org/wiki/Neutronium

bound state? resonance?

argued for half a century… (theories) unlikely to exist (most experiments) not observed


6

(1s1/2)2(1p3/2)2 dineutron-dineutron cluster

If a bound/resonant tetraneutron state does exist, some extraordinary mechanism should play a role.

??? ???


constraint on tetraneutron 7

D.R. Tilley et al., NPA 745, 155 (2004)

❖ 8He→4He+4n forbidden⇒ B.E.(4n)<3.1MeV

❖ 6He+2n dominance in 8He break-up⇒ B.E.(4n)<1MeV

❖ unbound 5H (→3H+2n)⇒ bound 4n unlikely


constraint on tetraneutron (cont’d) 8

D.R. Tilley et al., NPA 541, 1 (1992)

nolow-lying T=2 state

noT=2 resonance

4n?

(T=2)


bound tetraneutron in 14Be break-up 9# bi s pea or g p LB , nd B T param ters , b, c of Eq. 1# ste

gy s i he sh d a a o p n tused in the presen analy is; he p r en age of

FI 6 Sc ter plo

F. M. Marqués et al., PRC 65, 044006 (2002); see also arXiv:nucl-ex/0504009v1

10Be

single neutron (detected by a liquid scintillator)

a on may xp ct o app a 7# O g to pair g a df

the dr p-l e

x .

REVIEW C 65 4400

6 candidates of14Be break-up into

10Be+4n


incompatibility with other nuclides? 10

04 !0: 7, and ener y. The

-50

-40

-30

-20

-10

0

Ene

rgy

(MeV

)

1S0-2π 1S0-AV1′ AV18 Exp

0+

2n1+

2H1/2+

3H

0+

4n 2−

4H

1/2+

5H

0+

6n

6He 6Li

0+

8n

A

W

+

ese e orm

-120

-40

-20

0

Vijk Vijkl

p

1/2+

3H

0+

4n2−

4H0+

4He

1/2+

3/2−0+

6He

1+

Li

modified NN interactionchanges energies of other nuclides,

including di-neutron

0+

4n

i n

difi d S0inclusion of extra 3N or 4N interaction

drastically changesenergies of A>4 nuclides

S. C. Pieper, PRL 90, 252501 (2003)

“should the results of Ref. [1] be confirmed …,our current very successful understanding of nuclear forces

would have to be severely modifiedin ways that, at least to me, are not at all obvious.”


non-observation in transfer reaction 11

Fig 4 The I4 energy spe trum for he ‘Li “B, 0)4n reaction. The ull ine c fo the 40 + n a n he e it h n

8 V a p may pp ar from the reac on o t 65 MeV

of 1C nuc ei f om t e

θ1s

D. V. Aleksandrov et al. JETP Letters 81, 43 (2005).

A. V. Belozyorov et al., NPA 477, 131 (1988)

7Li(9Be,12N)4n

9Be(9Be,14O)4n7Li(11B,14O)4n


n11/2+

614.6 s

β-

H31/2+

12.33 y

β-

H42-

Li42-

H5

He53/2-

0.60 MeV

n

Li53/2-

1.5 MeV

p

Be5

H6

He60+

806.7 ms

β-

Be60+

92 keV

2p

He7(3/2)-

160 keV

n

Be73/2-

53.12 d

EC

B7(3/2-)

1.4 MeV

He80+

119.0 ms

β-n

Li82+

838 ms

β-2α

Be80+

6.8 eV

2α

B82+

770 ms

EC2α

C80+

230 keV

He9(1/2-)

0.30 MeV

n

Li93/2-

178.3 ms

β-n

B93/2-

0.54 keV

2pα

C9(3/2-)

126.5 ms

ECp,ECp2α,...

He100+

0.3 MeV

n

Li101.2 MeV

n

Be100+

1.51E+6 y

β-

C100+

19.255 s

EC

N10

Li113/2-

8.5 ms

β-n,β-2n,...

Be111/2+

13.81 s

β-α

C113/2-

20.39 m

EC

N111/2+

740 keV

p

Li12

Be120+

23.6 ms

β-

B121+

20.20 ms

β-3α

N121+

11.000 ms

EC3α

O120+

0.40 MeV

2p

Be13(1/2,5/2)+0.9 MeV

n

B133/2-

17.36 ms

β-n

N131/2-

9.965 m

EC

O13(3/2-)

8.58 ms

ECp

Be140+

4.35 ms

β-n,β-2n,...

B142-

13.8 ms

β-

C140+

5730 y

β-

O140+

70.606 s

EC

F14(2-)

p

B1510.5 ms

β-

C151/2+

2.449 s

β-

O151/2-

122.24 s

EC

F15(1/2+)

1.0 MeV

p

B16(0-)

200 Ps

n

C160+

0.747 s

β-n

N162-

7.13 s

β-α

F160-

40 keV

p

B17(3/2-)

5.08 ms

β-n

C17193 ms

β-n

N171/2-

4.173 s

β-n

F175/2+

64.49 s

EC

C180+

95 ms

β-n

N181-

624 ms

β-n,β-α,...

F181+

109.77 m

EC

β-n

N19(1/2-)

0.304 s

β-n

O195/2+

26.91 s

β-

β-n

O200+

13.51 s

β-

F202+

11.00 s

β-

(1/2

β-

F215/2+

4.158 s

β-

4

β-

H11/2+

99.985

H21+

0.015

He31/2+

0.000137

He40+

99.999863

Li61+

7.5

Li73/2-

92.5

Be93/2-

100

B103+

19.9

B113/2-

80.1

C120+

98.90

C131/2-

1.10

N141+

99.634

N151/2-

0.366

O160+

99.762

O175/2+

0.038

O180+

0.200

F191/2+

100

1H

91.0%1.00794

1 -259.34°-252.87°-240.18°

+1-1

2He

8.9%4.002602

2 -272.2°-268.93°-267.96°

0

3Li

1.86×10 -7%6.941

21

180.5°1342°

+1

4Be

2.38×10 -9%9.012182

22

1287°2471°

+2

5B

6.9×10 -8%10.811

23

2075°4000°

+3

6C

0.033%12.0107

24

4492t°3642s°

+2+4-4

7N

0.0102%14.00674

25

-210.00°-195.79°-146.94°

±1±2±3+4+5

8O

0.078%15.9994

26

-218.79°-182.95°-118.56°

-2

9F

2.7×10 -6%18.9984032

27

-219.62-188.12°-129.02°

-1

2 6 8

10 12

4n? transfer reaction

break-up reaction

Table of Isotopes


n11/2+

614.6 s

β-

H31/2+

12.33 y

β-

H42-

Li42-

H5

He53/2-

0.60 MeV

n

Li53/2-

1.5 MeV

p

Be5

H6

He60+

806.7 ms

β-

Be60+

92 keV

2p

He7(3/2)-

160 keV

n

Be73/2-

53.12 d

EC

B7(3/2-)

1.4 MeV

He80+

119.0 ms

β-n

Li82+

838 ms

β-2α

Be80+

6.8 eV

2α

B82+

770 ms

EC2α

C80+

230 keV

He9(1/2-)

0.30 MeV

n

Li93/2-

178.3 ms

β-n

B93/2-

0.54 keV

2pα

C9(3/2-)

126.5 ms

ECp,ECp2α,...

He100+

0.3 MeV

n

Li101.2 MeV

n

Be100+

1.51E+6 y

β-

C100+

19.255 s

EC

N10

Li113/2-

8.5 ms

β-n,β-2n,...

Be111/2+

13.81 s

β-α

C113/2-

20.39 m

EC

N111/2+

740 keV

p

Li12

Be120+

23.6 ms

β-

B121+

20.20 ms

β-3α

N121+

11.000 ms

EC3α

O120+

0.40 MeV

2p

Be13(1/2,5/2)+0.9 MeV

n

B133/2-

17.36 ms

β-n

N131/2-

9.965 m

EC

O13(3/2-)

8.58 ms

ECp

Be140+

4.35 ms

β-n,β-2n,...

B142-

13.8 ms

β-

C140+

5730 y

β-

O140+

70.606 s

EC

F14(2-)

p

B1510.5 ms

β-

C151/2+

2.449 s

β-

O151/2-

122.24 s

EC

F15(1/2+)

1.0 MeV

p

B16(0-)

200 Ps

n

C160+

0.747 s

β-n

N162-

7.13 s

β-α

F160-

40 keV

p

B17(3/2-)

5.08 ms

β-n

C17193 ms

β-n

N171/2-

4.173 s

β-n

F175/2+

64.49 s

EC

C180+

95 ms

β-n

N181-

624 ms

β-n,β-α,...

F181+

109.77 m

EC

β-n

N19(1/2-)

0.304 s

β-n

O195/2+

26.91 s

β-

β-n

O200+

13.51 s

β-

F202+

11.00 s

β-

(1/2

β-

F215/2+

4.158 s

β-

4

β-

H11/2+

99.985

H21+

0.015

He31/2+

0.000137

He40+

99.999863

Li61+

7.5

Li73/2-

92.5

Be93/2-

100

B103+

19.9

B113/2-

80.1

C120+

98.90

C131/2-

1.10

N141+

99.634

N151/2-

0.366

O160+

99.762

O175/2+

0.038

O180+

0.200

F191/2+

100

1H

91.0%1.00794

1 -259.34°-252.87°-240.18°

+1-1

2He

8.9%4.002602

2 -272.2°-268.93°-267.96°

0

3Li

1.86×10 -7%6.941

21

180.5°1342°

+1

4Be

2.38×10 -9%9.012182

22

1287°2471°

+2

5B

6.9×10 -8%10.811

23

2075°4000°

+3

6C

0.033%12.0107

24

4492t°3642s°

+2+4-4

7N

0.0102%14.00674

25

-210.00°-195.79°-146.94°

±1±2±3+4+5

8O

0.078%15.9994

26

-218.79°-182.95°-118.56°

-2

9F

2.7×10 -6%18.9984032

27

-219.62-188.12°-129.02°

-1

2 6 8

10 12

4n? transfer reaction

break-up reaction

Table of Isotopes double charge exchange reaction


candidates of resonant tetraneutron 14

186 MeV/u 8He beam (~2MHz)

8Be→2α momentum-analyzed

one 8He in one bunch(to avoid accidental coincidence)

the 8He beam was 99. %.

he momenta f two

h-r olut n s ec

y beam wa

for a

f l ofs

mr tspectrometer.


candidates of resonant tetraneutron 15K. Kisamori et al., PRL 116, 052501 (2016)

significance: 4.9 σ (w/ look-elsewhere effect) energy: 0.83±0.65±1.25 MeVwidth : <2.6MeV (FWHM) above 4n threshold (or not)?


ab-initio 4N calculation 16

Re(E) (MeV

the eye the resonance

HIYAMA, R LAZAUSKAS KA

−40 −30 −20 −10 0−14

−12

−10

−8

−6

−4

(a) T=1, Jπ=2−

3H+N threshold

3He+N

4Li4He

4H

W1(T=3/2) (MeV)

E (

MeV

)

3 N

introduction of strong 3N force→ 4H, 4He (I=1), 4Li below 3H(3He)+N threshold

E. Hiyama, R. Lazauskas, J. Carbonell, and M. Kamimura, PRC 93, 044004 (2016)


n11/2+

614.6 s

β-

H31/2+

12.33 y

β-

H42-

Li42-

H5

He53/2-

0.60 MeV

n

Li53/2-

1.5 MeV

p

Be5

H6

He60+

806.7 ms

β-

Be60+

92 keV

2p

He7(3/2)-

160 keV

n

Be73/2-

53.12 d

EC

B7(3/2-)

1.4 MeV

He80+

119.0 ms

β-n

Li82+

838 ms

β-2α

Be80+

6.8 eV

2α

B82+

770 ms

EC2α

C80+

230 keV

He9(1/2-)

0.30 MeV

n

Li93/2-

178.3 ms

β-n

B93/2-

0.54 keV

2pα

C9(3/2-)

126.5 ms

ECp,ECp2α,...

He100+

0.3 MeV

n

Li101.2 MeV

n

Be100+

1.51E+6 y

β-

C100+

19.255 s

EC

N10

Li113/2-

8.5 ms

β-n,β-2n,...

Be111/2+

13.81 s

β-α

C113/2-

20.39 m

EC

N111/2+

740 keV

p

Li12

Be120+

23.6 ms

β-

B121+

20.20 ms

β-3α

N121+

11.000 ms

EC3α

O120+

0.40 MeV

2p

Be13(1/2,5/2)+0.9 MeV

n

B133/2-

17.36 ms

β-n

N131/2-

9.965 m

EC

O13(3/2-)

8.58 ms

ECp

Be140+

4.35 ms

β-n,β-2n,...

B142-

13.8 ms

β-

C140+

5730 y

β-

O140+

70.606 s

EC

F14(2-)

p

B1510.5 ms

β-

C151/2+

2.449 s

β-

O151/2-

122.24 s

EC

F15(1/2+)

1.0 MeV

p

B16(0-)

200 Ps

n

C160+

0.747 s

β-n

N162-

7.13 s

β-α

F160-

40 keV

p

B17(3/2-)

5.08 ms

β-n

C17193 ms

β-n

N171/2-

4.173 s

β-n

F175/2+

64.49 s

EC

C180+

95 ms

β-n

N181-

624 ms

β-n,β-α,...

F181+

109.77 m

EC

β-n

N19(1/2-)

0.304 s

β-n

O195/2+

26.91 s

β-

β-n

O200+

13.51 s

β-

F202+

11.00 s

β-

(1/2

β-

F215/2+

4.158 s

β-

4

β-

H11/2+

99.985

H21+

0.015

He31/2+

0.000137

He40+

99.999863

Li61+

7.5

Li73/2-

92.5

Be93/2-

100

B103+

19.9

B113/2-

80.1

C120+

98.90

C131/2-

1.10

N141+

99.634

N151/2-

0.366

O160+

99.762

O175/2+

0.038

O180+

0.200

F191/2+

100

1H

91.0%1.00794

1 -259.34°-252.87°-240.18°

+1-1

2He

8.9%4.002602

2 -272.2°-268.93°-267.96°

0

3Li

1.86×10 -7%6.941

21

180.5°1342°

+1

4Be

2.38×10 -9%9.012182

22

1287°2471°

+2

5B

6.9×10 -8%10.811

23

2075°4000°

+3

6C

0.033%12.0107

24

4492t°3642s°

+2+4-4

7N

0.0102%14.00674

25

-210.00°-195.79°-146.94°

±1±2±3+4+5

8O

0.078%15.9994

26

-218.79°-182.95°-118.56°

-2

9F

2.7×10 -6%18.9984032

27

-219.62-188.12°-129.02°

-1

2 6 8

10 12

4n?Table of Isotopes

double charge exchange reaction

satisfies almost recoilless condition4He(8He,8Be)


n11/2+

614.6 s

β-

H31/2+

12.33 y

β-

H42-

Li42-

H5

He53/2-

0.60 MeV

n

Li53/2-

1.5 MeV

p

Be5

H6

He60+

806.7 ms

β-

Be60+

92 keV

2p

He7(3/2)-

160 keV

n

Be73/2-

53.12 d

EC

B7(3/2-)

1.4 MeV

He80+

119.0 ms

β-n

Li82+

838 ms

β-2α

Be80+

6.8 eV

2α

B82+

770 ms

EC2α

C80+

230 keV

He9(1/2-)

0.30 MeV

n

Li93/2-

178.3 ms

β-n

B93/2-

0.54 keV

2pα

C9(3/2-)

126.5 ms

ECp,ECp2α,...

He100+

0.3 MeV

n

Li101.2 MeV

n

Be100+

1.51E+6 y

β-

C100+

19.255 s

EC

N10

Li113/2-

8.5 ms

β-n,β-2n,...

Be111/2+

13.81 s

β-α

C113/2-

20.39 m

EC

N111/2+

740 keV

p

Li12

Be120+

23.6 ms

β-

B121+

20.20 ms

β-3α

N121+

11.000 ms

EC3α

O120+

0.40 MeV

2p

Be13(1/2,5/2)+0.9 MeV

n

B133/2-

17.36 ms

β-n

N131/2-

9.965 m

EC

O13(3/2-)

8.58 ms

ECp

Be140+

4.35 ms

β-n,β-2n,...

B142-

13.8 ms

β-

C140+

5730 y

β-

O140+

70.606 s

EC

F14(2-)

p

B1510.5 ms

β-

C151/2+

2.449 s

β-

O151/2-

122.24 s

EC

F15(1/2+)

1.0 MeV

p

B16(0-)

200 Ps

n

C160+

0.747 s

β-n

N162-

7.13 s

β-α

F160-

40 keV

p

B17(3/2-)

5.08 ms

β-n

C17193 ms

β-n

N171/2-

4.173 s

β-n

F175/2+

64.49 s

EC

C180+

95 ms

β-n

N181-

624 ms

β-n,β-α,...

F181+

109.77 m

EC

β-n

N19(1/2-)

0.304 s

β-n

O195/2+

26.91 s

β-

β-n

O200+

13.51 s

β-

F202+

11.00 s

β-

(1/2

β-

F215/2+

4.158 s

β-

4

β-

H11/2+

99.985

H21+

0.015

He31/2+

0.000137

He40+

99.999863

Li61+

7.5

Li73/2-

92.5

Be93/2-

100

B103+

19.9

B113/2-

80.1

C120+

98.90

C131/2-

1.10

N141+

99.634

N151/2-

0.366

O160+

99.762

O175/2+

0.038

O180+

0.200

F191/2+

100

1H

91.0%1.00794

1 -259.34°-252.87°-240.18°

+1-1

2He

8.9%4.002602

2 -272.2°-268.93°-267.96°

0

3Li

1.86×10 -7%6.941

21

180.5°1342°

+1

4Be

2.38×10 -9%9.012182

22

1287°2471°

+2

5B

6.9×10 -8%10.811

23

2075°4000°

+3

6C

0.033%12.0107

24

4492t°3642s°

+2+4-4

7N

0.0102%14.00674

25

-210.00°-195.79°-146.94°

±1±2±3+4+5

8O

0.078%15.9994

26

-218.79°-182.95°-118.56°

-2

9F

2.7×10 -6%18.9984032

27

-219.62-188.12°-129.02°

-1

2 6 8

10 12

4n?Table of Isotopes

double charge exchange reaction

satisfies almost recoilless condition4He(8He,8Be) 4He(π-,π+)


examples of pion DCX measurements 19

n11/2+

614.6 s

β-

H31/2+

12.33 y

β-

H42-

Li42-

H5

He53/2-

0.60 MeV

n

Li53/2-

1.5 MeV

p

Be5

H6

He60+

806.7 ms

β-

Be60+

92 keV

2p

He7(3/2)-

160 keV

n

Be73/2-

53.12 d

EC

B7(3/2-)

1.4 MeV

He80+

119.0 ms

β-n

Li82+

838 ms

β-2α

Be80+

6.8 eV

2α

B82+

770 ms

EC2α

C80+

230 keV

n

Li93/2-

178.3 ms

β-n

B93/2-

0.54 keV

2pα

C9(3/2-)

126.5 ms

ECp,ECp2α,...

n

Be100+

1.51E+6 y

β-

C100+

19.255 s

EC

N10

Be111/2+

13.81 s

β

C113/2-

20.39 m

EC

N111/2+

740 keV

p

Be120+

23.6 ms

β

B121+

20 20 ms

β-3α

N121+

11.000 ms

EC3α

O120+

0.40 MeV

2p

Be13(1/2,5/2)+0.9 MeV

B133/2-

17.36 ms

β-n

N131/2-

9.965 m

EC

O13(3/2-)

8.58 ms

ECp

Be140+

4.35 ms

β β 2

B142-

13.8 ms

β-

C140+

5730 y

β-

O140+

70.606 s

EC

14(2-)

B1510.5 ms

β-

C151/2+

2.449 s

β-

O151/2-

122.24 s

EC

1/ +0 MeV

B16(0-)

200 Ps

n

C160+

0.747 s

β-n

N162-

7.13 s

β-α

0-0 keV

B17(3/2-)

5.08 ms

β-n

C17193 ms

β-n

N171/2-

4.173 s

β-n

5/6 .49 s

C180+

95 ms

β-n

N181-

624 ms

β-n,β-α,...

1109.7 m

N19(1/2-)

0.304 s

β-n

O195/2+

26.91 s

β-

O200+

13.51 s

β-

F.

H11/2+

99.985

H21+

0.015

He31/2+

0.000137

He40+

99.999863

Li61+

7.5

Li73/2-

92.5

Be93/2-

100

B103+

19.9

B113/2-

80.1

C120+

98.90

C131/2-

1.10

N141+

99.634

N151/2-

0.366

O160+

99.762

O175/2+

0.038

O180+

0.200

/2+

1H

91.0%1.00794

1 -259.34°-252.87°-240.18°

+1-1

2He

8.9%4.002602

2 -272.2°-268.93°-267.96°

0

3Li

1.86×10 -7%6.941

21

180.5°1342°

+1

4Be

2.38×10 -9%9.012182

22

1287°2471°

+2

5B

6.9×10 -8%10.811

23

2075°4000°

+3

6C

0.033%12.0107

24

4492t°3642s°

+2+4-4

7N

0.0102%14.00674

25

-210.00°-195.79°-146.94°

±1±2±3+4+5

8O

0.078%15.9994

26

-218.79°-182.95°-118.56°

-2

9F

°12 °

-1

2 4 6

12

F mat c o xperim se up

thr ld Che he n

ns ored r e-e ntt oun esc p 30 e hesc d a g e

l r icl n rif

a y to houg had ec of ng

soluti o a out 8 MeVx ll

ora o ngleab lut br ion ei er ha n le spect o e ma has th curacyor easu ere ore

esse t d a atio

~ 25 Vm ) tunate ch aen l ab e ea tioi h V

(ta ge 0an nd rt r ed cha ica d m gn

h m tp mon

e pe ipart in

d a

F G 2 S

K.K. Seth et al., PRL 41, 1589 (1978)



n11/2+

614.6 s

β-

H31/2+

12.33 y

β-

H42-

Li42-

H5

He53/2-

0.60 MeV

n

Li53/2-

1.5 MeV

p

Be5

H6

He60+

806.7 ms

β-

Be60+

92 keV

2p

He7(3/2)-

160 keV

n

Be73/2-

53.12 d

EC

B7(3/2-)

1.4 MeV

He80+

119.0 ms

β-n

Li82+

838 ms

β-2α

Be80+

6.8 eV

2α

B82+

770 ms

EC2α

C80+

230 keV

He9(1/2-)

0.30 MeV

n

Li93/2-

178 3 ms

β-n

B93/2-

0.54 keV

2pα

C9(3/2-)

126.5 ms

ECp,ECp2α,...

He100+

0.3 MeV

n

Li101.2 MeV

n

1

β-

C100+

19.255 s

EC

N10

Li113/2-

8.5 ms

β-n,β-2n,...

β-α

C113/2-

20.39 m

EC

N111/2+

740 keV

p

Li12

β-

N121+

11.000 ms

EC3α

O120+

0.40 MeV

2p

n

EC

O13(3/2-)

8.58 ms

ECp

β-n,β-2n,...

EC

14(2-)

1/ +0 MeV

0-0 keV

5/26 .49 s

1109.7 m

F

H11/2+

99.985

H21+

0.015

He31/2+

0.000137

He40+

99.999863

Li61+

7.5

Li73/2-

92.5

Be93/2-

100

B103+

19.9

/2+

1H

91.0%1.00794

1 -259.34°-252.87°-240.18°

+1-1

2He

8.9%4.002602

2 -272.2°-268.93°-267.96°

0

3Li

1.86×10 -7%6.941

21

180.5°1342°

+1

4Be

2.38×10 -9%9.012182

22

1287°2471°

+2

5B

6.9×10 -8%10.811

23

2075°4000°

+3

6C

0.033%12.0107

24

4492t°3642s°

+2+4-4

7N

0.0102%14.00674

25

-210.00°-195.79°-146.94°

±1±2±3+4+5

8O

0.078%15.9994

26

-218.79°-182.95°-118.56°

-2

9F

°12 °

-1

2 4 6 8

10

K.K. Seth et al., PRL 58, 1930 (1987)

OLUME 58 NUMBER 19 P CAL

and C targets were do e with the a

was FWHM

F . M -mas p ct un+) 9H f r ) = l b =

ol oml k h

he po nom al r ofoly p rM m l



n11/2+

614.6 s

β-

H31/2+

12.33 y

β-

H42-

Li42-

H5

He53/2-

0.60 MeV

n

Li53/2-

1.5 MeV

p

Be5

H6

He60+

806.7 ms

β-

Be60+

92 keV

2p

He7(3/2)-

160 keV

n

Be73/2-

53.12 d

EC

B7(3/2-)

1.4 MeV

He80+

119.0 ms

β-n

Li82+

838 ms

β-2α

Be80+

6.8 eV

2α

B82+

770 ms

EC2α

C80+

230 keV

He9(1/2-)

0.30 MeV

n

Li93/2-

178.3 ms

β-n

B93/2-

0.54 keV

2pα

C9(3/2-)

126.5 ms

ECp,ECp2α,...

He100+

0.3 MeV

n

Li101.2 MeV

n

Be100+

1.51E+6 y

β-

C100+

19.255 s

EC

N10

Li113/2-

8.5 ms

β-n,β-2n,...

Be111/2+

13.81 s

β-α

C113/2-

20.39 m

EC

N111/2+

740 keV

p

Li12

Be120+

23.6 ms

β-

B121+

20.20 ms

β-3α

N121+

11.000 ms

EC3α

O120+

0.40 MeV

2p

Be13(1/2,5/2)+0.9 MeV

n

B133/2-

17.36 ms

β-n

N131/2-

9.965 m

EC

O13(3/2-)

8.58 ms

ECp

Be140+

4.35 ms

β-n,β-2n,...

B142-

13.8 ms

β-

C140+

5730 y

β-

O140+

70.606 s

EC

14(2-)

B1510.5 ms

β-

C151/2+

2.449 s

β-

O151/2-

122.24 s

EC

1/ +0 MeV

B16(0-)

200 Ps

n

C160+

0.747 s

β-n

N162-

7.13 s

β-α

0-0 keV

B17(3/2-)

5.08 ms

β-n

C17193 ms

β-n

N171/2-

4.173 s

β-n

5/6 .49 s

C180+

95 ms

β-n

N181-

624 ms

β-n,β-α,...

1109.7 m

N19(1/2-)

0.304 s

β-n

O195/2+

26.91 s

β-

O200+

13.51 s

β-

4

H11/2+

99.985

H21+

0.015

He31/2+

0.000137

He40+

99.999863

Li61+

7.5

Li73/2-

92.5

Be93/2-

100

B103+

19.9

B113/2-

80.1

C120+

98.90

C131/2-

1.10

N141+

99.634

N151/2-

0.366

O160+

99.762

O175/2+

0.038

O180+

0.200

/2+

1H

91.0%1.00794

1 -259.34°-252.87°-240.18°

+1-1

2He

8.9%4.002602

2 -272.2°-268.93°-267.96°

0

3Li

1.86×10 -7%6.941

21

180.5°1342°

+1

4Be

2.38×10 -9%9.012182

22

1287°2471°

+2

5B

6.9×10 -8%10.811

23

2075°4000°

+3

6C

0.033%12.0107

24

4492t°3642s°

+2+4-4

7N

0.0102%14.00674

25

-210.00°-195.79°-146.94°

±1±2±3+4+5

8O

0.078%15.9994

26

-218.79°-182.95°-118.56°

-2

9F

°12 °

-1

2 6 8

10 12

4n?


4He(π−,π+) reaction❖ Ungar et al.: Tπ=165MeV, θπ=0° @ LAMPF → dσ/dΩ = 7±15nb/sr

❖ Gorringe et al.: Tπ=80MeV, 50°<θπ<130° @ TRIUMF→ dσ/dΩ <13nb/sr

22

Se

u d pec e .

J.E. Ungar et al., PLB 144 (1984) 333

The beam ntensitymo e tum bit s

e m tum o n/c The accepta ce wa t mine t be

n ei c was f un o b r e enden ; a

e on s r unding t T a anu nted b S l T ese os t ve o s reduce

m er acce ta e Co se ue t yeptan e had b o r cted for

s m nSe n y due to o l mit d mo

c t t f "He m

in ow ob ne s o owsMe /c of s ec m b) on ains 2

p

0 100 20 1 0 160 180

m from

F

0 50 — af er all of waree

T.P. Gorringe et al., PRC 40 (1989) 2390

(BG subtracted)


cf. 6Li(π−,K+) reaction (pπ=1.2GeV/c) 23[ ], .

l ci le ho he e ent result

A magn fi d view around he Λ

H. Sugimura et al. (J-PARC E10 collaboration), Phys. Lett. B 729 (2014) 39upper limit of 6ΛH formation cross section: 1.2nb/sr (90% C.L.)


revisiting pion-DCX reaction❖ searching for a very weak peak near 4n threshold

‣ not only in the bound region but in the unbound region

❖ reduction of unphysical background is important

‣ contribution from target cell

‣ PID of projectiles and ejectiles

‣ beam contaminant, π± decay in flight,single-charge-exchange followed by π0→2γ, γ→e+e−

❖ High-Energy (far above Δ region) + High-Intensity + High-Resolution experiment will improve the sensitivity

24


J-PARC HIHR beamline 25

Extended Hadron Hall

5

• < 2.0 GeV/c • ~106 K-/spill

Muon • 30 GeV proton • <31 GeV/c unseparated 2ndary

beams (mostly pions), ~107/spill

• < 1.1 GeV/c • ~105 K-/spill

• < 1.2 GeV/c • ~106 K-/spill

• <10 GeV/c separated pion, kaon, pbar

• ~107/spill K-, pbars

• 5 deg extraction • ~5.2 GeV/c K0

• Good n/K

• < 2.0 GeV/c • 1.8x108 pion/spill • x10 better Dp/p

105 m

(in a planning stage)


J-PARC HIHR beamline 26

17

HIHR LineJ-PARC ExHH

A23

ElectrostaticSeparator

Prod. T

High Res.Spectrometer

Exp. Target

Mass Slit

AchromaticFocus

Intensity: ~ 1.8x108 pion/pulse(1.2 GeV/c, 58 m, 1.4msr*%,

100kW, 6s spill, Pt 60mm)Dp/p ~ 1/10000

0.E+00

1.E+08

2.E+08

3.E+08

4.E+08

5.E+08

6.E+08

7.E+08

0.5 1 1.5 2

Beam

Inte

nsity

[pio

ns/6

s]

Beam Momentum [GeV/c]

H. Noumi, “International workshop on physics at the extended hadron experimental facility of J-PARC”

high-precision Λ hypernuclear spectroscopy w/ (π±, K+)FWHM: 300keV


experimental condition (tentative)

❖ 850MeV π- beam

❖ beam intensity ~1.6×108 / spill (Sanford-Wang formula)

❖ momentum transfer ~ 31MeV/c

❖ With 2 g/cm2 liquid 4He target,formation cross section 1nb/sr ⇒ 97 events in 2 weeks

27


pion DCX reaction above Δ region 28

cita ion ener y spectrum for t e 9Be(14C 14 O

d n an l g tra si ion o

n n-analog tra nly

available data < 550MeV (LAMPF)

D.P. Beatty et al., PRC 48, 1428 (1993)

ai e

r l

theory

E. Oset and D. Strottman, PRL 70, 146 (1993)


phase-0 experiment 29

Letter of Intent for J-PARC 50GeV Synchrotron

Investigation of Pion Double Charge Exchange Reaction with S-2S Spectrometer

H. Fujioka,∗ S. Kanatsuki, T. Nagae, and T. NanamuraDepartment of Physics, Kyoto University

T. Fukuda and T. HaradaOsaka Electro-Communication University

E. Hiyama, K. Itahashi, and T. NishiRIKEN Nishina Center(Dated: June 27, 2016)

We will study pion double charge exchange (π±,π∓) reactions with approximately 850MeV(980MeV/c) π beams at J-PARC. The ultimate goal is to search for a tetraneutron resonancestate (4n), whose candidates have been observed in the 4He(8He, 8Be) reaction at RIBF. First of all,an analog transition, the 18O(π+,π−)18Ne (g.s.) reaction, will be investigated at the existing K1.8beamline with the S-2S spectrometer. It will be an important step toward a non-analog transition,the 4He(π−,π+)4n reaction, with much smaller cross section.

http://j-parc.jp/researcher/Hadron/en/Proposal_e.html


phase-0 experiment❖ 18O(π+, π-)18Ne(g.s.) at existing K1.8 beamline

‣ + S-2S spectrometer(constructed for Ξ-hypernuclear spectroscopy)

‣ first investigation far above Δ-resonance region

‣ large cross section expected(because of analog transition)

‣ cf. 4He (I=0) → 4n (I=2) : non-analog transition

‣ 400 counts per day(with 107 π+/spill impinging on 2 g/cm2 H218O target)

30


conclusion

❖ Recent observation of tetraneutron bound/resonance states challenges our understanding on nuclear force and few-body systems.

❖ From an experimental point of view, an independent approach with a different reaction will be meaningful.

❖ We propose to investigate the pion double charge exchange reaction with Tπ ~ 850 MeV at J-PARC.

❖ As phase-0, we will examine an analog transition (18O→18Ne) at K1.8 beamline with S-2S spectrometer.

31

Documents

Search for Tetraneutron in the He(π Reaction...Li modi#ed NN interaction changes energies of other nuclides, including di-neutron 0+ 4n i n difi d S0 inclusion of extra 3N or 4N interaction