Light nucleus clustering in fragmentation above 1 A GeV

N. P. Andreevaa, D. A. Artemenkovb,V. Bradnovab, M. M. Chernyavskyc, A. Sh. Gaitinova, S. P. Kharlamovc, A. D. Kovalenkob, М. Haiducd, S. G. Gerasimovc, L. A. Goncharovac, N. Kachalovab

V. G. Larionovac, F. G. Lepekhine, A. I. Malakhovb, A. A. Moiseenkof, G. I. Orlovac, N. G. Peresadkoc, N. G. Polukhinac, P. A. Rukoyatkinb, V. V. Rusakovab, V. R. Sarkisyanf, T. V. Schedrinab, B. B. Simonove, E.

Stane, R. Stanoevag, I. Tsakovg, S. Vokalh, P. I. Zarubinb, I.G Zarubinab

aInsitutute of Physics and Technology, Almaty, KazakhstanbJoint Institute for Nuclear Research, Dubna, Russia

cP. N. Lebedev Physical Institute, RAS, Moscow, RussiadInstitute of Space Sciences, Bucharest-Magurele, Romania

ePetersburg Institute of Nuclear Physics, RAS, Gatchina, RussiafErevan Physical Institute, Erevan, Armenia

gInsttitute for Nuclear Research and Nuclear Energy, BAS, Sofia, BulgariahP. J. Safarik University, Kosice, Slovakia

4.5 A GeV/c 4.5 A GeV/c 1616O O

4.5A GeV/c 4.5A GeV/c 1616OO

2.9A GeV/c 2.9A GeV/c 1414NN

1414N Dissociation with N Dissociation with 88Be like Be like fragmentationfragmentation

3 after

proton

Mg-SiMg-Si Dissociation into Dissociation into charge state charge state

2+2+2+2+2+12+2+2+2+2+1

5 +proton

4.5A GeV/c 4.5A GeV/c 2020Ne Peripheral Dissociation into charge stateNe Peripheral Dissociation into charge state

2+2+2+2+2 with 2+2+2+2+2 with 88Be like fragmentsBe like fragments

4.5A GeV/c 4.5A GeV/c 2424Mg Peripheral Dissociation into charge stateMg Peripheral Dissociation into charge state

2+2+2+2+2+2 with 2+2+2+2+2+2 with 88Be and Be and 1212CC** like fragments like fragments

dN/dTn

Tn=(M*n - n M )/(4 n ), MeV

0

0.8 1.6 2.4

4.5A GeV/c12C:<T3>=0.4 MeV

22Ne5 24Mg5 +3He

Boltzmann constant, k /approx 10-4 eV K-1

Typical Temperature Range, Ŧ /approx 5∙108-9 K per α

pα=√(2mα ∙Tα) pα /approx 20-120 MeV

Planck constant, ħ /approx 200 MeV fm

λ=ħ/p de Broglie wave lengths /approx 1-10 fm

λcohα /approx Rα λcoh

He /approx RHe

Tα/THe= Ŧα/ Ŧ He= (RHe/Rα)2 /approx 1010

Macroscopic quantum coherence phenomena in atomic physics /approx 1 K

Macroscopic quantum coherence phenomena in atomic physics /approx 1010 K

The common topological feature for fragmentation of the Ne, Mg, and Si nuclei consists in a

suppression of binary splitting to fragments with charges larger than 2.

The growth of the fragmentation degree is revealed in an increase of the multiplicity of singly and doubly charged fragments up to complete dissociation with

increasing of excitation. This circumstance shows in an obvious way on a

domination of the multiple cluster states having high density over the binary states having lower energy

thresholds.

158 A GeV/c Pb158 A GeV/c Pb

158 A GeV/c Pb158 A GeV/c Pb

CClluusstteerriinngg iinn LLiigghhtt NNuucclleeiitt

33HHee

66LLii

77LLii

66HHee

77BBee

88BB

1122CC

1100BB

1122NN

1111BB

1111CC

99BBee

1100CC

Secondary beams of light radioactive nuclei will be produced mostly via charge exchange reactions. 8B and 9Be beams has been formed via fragmentation of 10B.

Clustering building blocks: more than one nucleon bound, stable & no exited states below particle decay thresholds – deuteron, triton, 4He, and 3He nuclei

pp process

dd fusion

A=4

+ or e - capture

Hep Process

A=5

A=6=0.092 MeV

++4.5A GeV/c 4.5A GeV/c 66Li Coherent Li Coherent Dissociation (PAVICOM image)Dissociation (PAVICOM image)

66LLii

Triton Clustering

7Li

7Li. About 7% of all inelastic interactions of 7Li nuclei are “white” stars (80 events).

Decay of 7Li nucleus to -particle and triton - 40 events.

=1.5 MeV

=0.092 MeV

=0.23 MeV

=1.4 MeV

=1.58 MeV

5Li

6Be

7B

8C

11N

Toward stability frontier

Splitting to HeHe with two target fragments,

HeHe, HeHH, 6Lip, and 4H.

2 A GeV/c 7Be.

Relativistic 7Be fragmentation: 2+2

The 7Вe*3He decay is occured in 22 “white stars” with 2+2 topology. In the latter, 5 “white” stars are identified as the 7Вe*(n) 3He3He decay. Thus, a 3He clustering is clearly

demonstrated in dissociation of the 7Be nucleus.

“Ternary H&He Process”

+

8B 0.769 s

The 10B nuclei with a momentum of 2A GeV/c and an intensity of about 108 nuclei per cycle were accelerated at

the JINR nuclotron. A beam of secondary nuclei of a magnetic rigidity corresponding to Z/A = 5/8 (10В8B

fragmentation) was provided for emulsions. We plan to determine the probabilities

8B7Bер (9), 3,4He3Hep (8), 6Lipp (1), HeHHp (7) , and HHHpp (1).

A=8=0.23 MeV

 8He (118 ms) , 8Li (838 ms)

(770 ms)

=0.0000068 MeV

A=9

=0.00054 MeV

1.3A GeV 9Be dissociation in 2+2. 10B9Be, Nuclotron, 2004.

“white” star

with recoil proton

with heavy fragment of target nucleus

“Ternary 3He Process”

+

9C 0.1265 s9B 540 eV

6Be & 3He

2 A GeV/c carbon beam of a magnetic rigidity Z/A = 6/9 (12C9C) was provided for emulsions to determine the probabilities

9C 8Bp (1) , 7Bерp (2) , HeHepp (7), 6Lipp (0) , HeHHpp (5) , HeHeHe (3).

1.9 A GeV 1.9 A GeV 1010BB

10B is disintegrated to 2 doubly charged and 1singly

charged particles in 70% of “white” stars. A singly charged particle is the deuteron in 40% like in

case of 6Li. 8Be contribution is 20%.

10В9Bep – 3%

=1.58 MeV

A=11

“3He Process: mixed isotope fusion”

+

11C 20.38 m

13O 8.58 ms

6Be & 4He

12N 11.0 ms +

14O 70.6 s

15O 122 s

+ 11B 80.2 %

CNO cycle

12C 98.89 %

7Be 53.3 d

10C 19.2 s

10B 19.8%

14O 70.6 s

11N 1.58 MeV

12O 0.4 MeV

15F 1 MeV

13N 10 min

20Na 448 ms

20Mg 95 ms

Walking along proton stability line

12N 11 ms

16Ne 0.122 MeV

14N 99.6%

13O 8.58 ms 14O 70.6 s

15O 122 s 16O 99.8%

19F 100%

20Ne 90.48%

16F 0.04 MeV17F 64.5 s 18F 110 min

17Ne 109 s 18Ne 1.67 s 19Ne 17.2 s

12O 0.4 MeV

9C, 126.5 ms

6Be, 0.092 MeV

+12 MeV

+16 MeV

+38 MeV

Multifragmentation in H&He

10C 19.2 s

13O 8.58 ms

16Ne 0.122 MeV

Multifragmentation in H&He

11C 20.38 m

14O 70.6 s

17Ne 109 s

20Mg 95 ms

Multifragmentation in H&He

Fragmentation of relativistic nuclei provides an excellent quantum “laboratory” to explore the transition of nuclei from the ground state to a gas-like phase composed of nucleons and few-nucleon clusters having no excited states, i. e. d, t, 3He, and .

The research challenge is to find indications for the formation of quasi-stable systems significantly exceeding the sizes of the fragments. Search for such states is of interest since they can play a role of intermediate states for a stellar nuclear fusion due to dramatically reduced Coulomb repulsion.

The fragmentation features might assist one to disclose the scenarios of few-body fusions as processes inverse to fragmentation.

2 A GeV/c 2 A GeV/c 1010B B 88BB