Peripheral fragmentation of Peripheral fragmentation of 77Li, Li, 77Be and Be and 8,10,118,10,11BB

relativistic nuclei inrelativistic nuclei in nuclear track emulsionnuclear track emulsion

P. I. Zarubin (JINR, Dubna) P. I. Zarubin (JINR, Dubna) for BECQUEREL Collaborationfor BECQUEREL Collaboration

Clustering building blocks: Clustering building blocks: more than one nucleon bound, stable & more than one nucleon bound, stable & no exited states below particle decay no exited states below particle decay thresholds – deuteron, triton, thresholds – deuteron, triton, 44He, and He, and 33He nucleiHe nuclei

=1.5 MeV

=0.092 MeV

=0.23 MeV

=1.4 MeV

=1.58 MeV

5Li

6Be

7B

8C

11N

Toward stability frontierToward stability frontier

66BeBe

77Be Be

88BB

99CC

Pure Pure 33He Nucleus Clustering He Nucleus Clustering in Light Nuclei ?in Light Nuclei ?

12O, 0.4 MeV

9C, 126.5 ms

6Be, 0.092 MeV+12 MeV

+16 MeV

+38 MeV

10C, 19.2 s

10B

+

+

11C, 20.38 m

14O, 70.6 s

17Ne, 109 s

20Mg, 95 ms

11B

+

14N

10C, 19.2 s

13O, 8.58 ms

16Ne, 0.122 MeV

7Be, 53 days

13N, 10 min

+

+

+

14O, 0.122 MeV

13C

14N

CClluusstteerriinngg iinn LLiigghhtt NNuucclleeiitt

33HHee

66LLii

77LLii

66HHee

77BBee

88BB

1122CC

1100BB

1122NN

1111BB

1111CC

99BBee

1100CC

Emulsion stacks are exposed in «beam cocktails» of 9C&8He, 9Be & 7Li, and 8B & 7Be nuclei produced via primary 12C and 10B fragmentation.

10B 12C

8B 7Be

9Be

9C3He

7Li

Deuteron-Alpha Clustering Deuteron-Alpha Clustering in Light Nucleiin Light Nuclei

1010B (19.9%)B (19.9%)

66Li (7.5%)Li (7.5%)

1414N (99.634%)N (99.634%)

22H (0.015%)H (0.015%)

4.5A GeV/c4.5A GeV/c 66LiLi66LLii

About 7% of all inelastic About 7% of all inelastic interactions of interactions of 77Li nuclei are Li nuclei are

“white” stars -80 events.“white” stars -80 events.

77Li →Li →αα+t - 40 events. +t - 40 events.

Scintillation counter Scintillation counter in front of emulsion stack:in front of emulsion stack:

Amplitude spectrumAmplitude spectrumStrobe&1H

3He

Li

7Be

1.2A GeV 1.2A GeV 77BeBe

1.2A GeV 1.2A GeV 77BeBe

1.6

MeV

5.6

6.9

25.3

21.2

1.0A GeV 1.0A GeV 1010BB

1010B→B→22He+H He+H 70% of “white”stars70% of “white”stars. . H – deuteron inH – deuteron in 40%40%

((likelike 66LiLi)). . 1010ВВ99Bep – 3%Bep – 3%

1.2A GeV 1.2A GeV 1010B B 88BB

1.2A GeV 1.2A GeV 88BB

Q B Be Li He H Ntf Nws

Protons Protons vsvs PPTT inin « «whitewhite» » starsstars 88BB→→77BeBe++pp andand PPTT

** in c.m.sin c.m.s 77BeBe++pp..

<<PPTT>=73 >=73 MeV/cMeV/c

<<PPTT>=52 >=52 MeV/cMeV/c

PPTT ( (88B) in “white” stars B) in “white” stars 77Be+pBe+p

Azimuthal angle Azimuthal angle εεi n “white” stars i n “white” stars 77Be+pBe+p

1.2A GeV 1.2A GeV 88BB

Yields of Yields of 1111ВВ Fragments Fragments

A. VokalovaA. Vokalova

andand

S. Vokal, J. VrlakovaS. Vokal, J. Vrlakova, , M. KarabovaM. KarabovaСеминар посвященый 90-летию со дня рождения К.Д.ТолстоваСеминар посвященый 90-летию со дня рождения К.Д.Толстова

““Исследование процессов фрагментации релятивистских ядер на Нуклотроне Исследование процессов фрагментации релятивистских ядер на Нуклотроне методом ядерных фотоэмульсийметодом ядерных фотоэмульсий””

Дубна, 4-5 октября 2005г.Дубна, 4-5 октября 2005г.

AmongAmong 116 116 starsstars NNhh=0=0 и и NNss=0=0 (N (Nh=h=NNgg+N+Nbb))

Q4 4 2 1 N

6 1 1 4

5 2 1 6

5 1 3 1

AVI MOV

11B11C

10B 10C

10B 9Be 9C

AVI

MOV

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