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Light nucleus clustering in fragmentation above 1 A GeV N. P. Andreeva a , D. A. Artemenkov b ,V. Bradnova b , M. M. Chernyavsky c , A. Sh. Gaitinov a , S. P. Kharlamov c , A. D. Kovalenko b , М . Haiduc d , S. G. Gerasimov c , L. A. Goncharova c , N. Kachalova b
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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, Kazakhstan bJoint Institute for Nuclear Research, Dubna, Russia cP. N. Lebedev Physical Institute, RAS, Moscow, Russia dInstitute of Space Sciences, Bucharest-Magurele, Romania ePetersburg Institute of Nuclear Physics, RAS, Gatchina, Russia fErevan Physical Institute, Erevan, Armenia gInsttitute for Nuclear Research and Nuclear Energy, BAS, Sofia, Bulgaria hP. J. Safarik University, Kosice, Slovakia
14N Dissociation with 8Be like fragmentation proton 3 after
Mg-Si Dissociation into charge state 2+2+2+2+2+1 5 +proton
4.5A GeV/c 20Ne Peripheral Dissociation into charge state 2+2+2+2+2 with 8Be like fragments
4.5A GeV/c 24Mg Peripheral Dissociation into charge state 2+2+2+2+2+2 with 8Be and 12C* like fragments
dN/dTn 4.5A GeV/c12C:<T3>=0.4 MeV 22Ne5 24Mg5 +3He 0 1.6 2.4 0.8 Tn=(M*n - n M )/(4 n), MeV
Boltzmann constant, k /approx10-4 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 RαλcohHe /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.
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
Hep Process + or e - capture
=0.092 MeV A=6
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.
Toward stability frontier =1.58 MeV 11N =0.23 MeV 8C =1.4 MeV 7B =0.092 MeV 6Be =1.5 MeV 5Li
2 A GeV/c 7Be. Splitting to HeHe with two target fragments, HeHe, HeHH, 6Lip, and 4H.
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 (770 ms) 8He (118 ms) , 8Li (838 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” 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). 9C 0.1265 s 9B 540 eV + 6Be & 3He
1.9 A GeV 10B 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” 12C 98.89 % + 12N 11.0 ms 11C 20.38 m 14O 70.6 s CNO cycle 7Be 53.3 d 15O 122 s + 11B 80.2 % + 10B 19.8% 10C 19.2 s 14O 70.6 s 6Be & 4He 13O 8.58 ms
Walking along proton stability line 20Mg 95 ms 20Na 448 ms 16Ne 0.122 MeV 17Ne 109 s 18Ne 1.67 s 19Ne 17.2 s 15F 1 MeV 20Ne 90.48% 12O 0.4 MeV 13O 8.58 ms 14O 70.6 s 17F 64.5 s 19F 100% 16F 0.04 MeV 18F 110 min 11N 1.58 MeV 15O 122 s 16O 99.8% 12N 11 ms 13N 10 min 14N 99.6%
Multifragmentation in H&He 6Be, 0.092 MeV +12 MeV 9C, 126.5 ms +16 MeV 12O 0.4 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
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.