XVIII International Baldin Seminar on High Energy Physics Problems

1. XVIII International Baldin Seminar on High Energy Physics Problems "RELATIVISTIC NUCLEAR PHYSICS & QUANTUM CHROMODYNAMICS“ Dubna, September27, 2006 Relativistic Secondary Nuclei Fragments Beams: a resent years practice at LHE P.A. Rukoyatkin, L.N. Komolov, R.I. Kukushkina, V.N. Ramzhin, P.I. Zarubin Veksler and Baldin Laboratory of High Energies Joint Institute for Nuclear Research Supported by Russian Foundation for Basic Research ( 04-02-17151 )

2. LHE Accelerator Facility Polaris – d­ EBIS – N, Ar, Fe … Laser – Li, B, C, F, Mg … Duoplasmotron – p, d, a, 3He SYNCHROPHASOTRON Internal target Experimental hall 205 NUCLOTRON – 6 GeV/n Experimental hall Experimental hall 1B

3. Some Nuclotron beams * A.V. Butenko et al., EPAC 2002 ** E.D. Donets et al., Rev. Sci. Instr. 75, (2004)

4. Nuclotron slow extraction Beam profiles at the F5 focus. Deuterons, pbeam= 4.3GeV/c, sx = 2.6mm, sy = 3.0mm x,mm y,mm An extracted beam spill (Nuclotron Dec. 2003 run) V.Volkov et al., EPAC 2004

5. Nuclotron external beam lines 5v 3v 6v GIBS DELTA-SIGMA • Lines Pmax Imax • ( GeV/c ) ( ppc ) • VP-1 15 1012 • 1v 9 108 • 3v 9 109 • 4v 9 107 • 5v 12 107 • 6v 12 107 FAZA f6 SPHERA Polarized Proton Target NIS 4v 3v 4v 1v f5 STRELA VP-1 Bending magnets f4 Quadrupole lenses MARUSYA Dump, shield f3 experimental area VP-1 f3 Slowly extracted beam

6. Secondary relativistic fragments beams: a general scheme Primary beam Projectile fragments Separation system Analyzing detectors p0Ai/Zi p0Ak/Zk 0 A0, Z0, p0 A0, Z0, p0 +  (Ai, Zi, p0) 0 0 A0, Z0 Tagging detectors (option) Primarybeamdump Target p0 -- projectile momentum per nucleon

7. Secondary relativistic fragment beams: relations Fragment momentum spread in the projectile rest frame s0 90 MeV/c A – projectile mass number B – fragment mass number A.S. Goldhaber, Phys. Lett. 53B, p.306 Fragment angular and relative momentum spread in the laboratory frame p0 – projectile momentum per nucl. b0– projectile velocity m – nucleon mass A numerical illustration 10B  8B ( A=10, B=8 ) at p0 = 2 GeV/c/nucl. (t0 1.3 GeV/nucl.) : sq 7.5 mr, sd 1.8 %

8. Secondary relativistic fragment beams: rigidity scale neighborhood Example: 10B  8B fragmentation 8B 3He 7Be (p-p0)/z, %

9. The lightest relativistic fragment beams P  1 – 4.5 GeV/c I*pol.= 2 – 4.106 , I*unol. 108 Polarization 0.55 Line/setup: 1v(NBL) / PPT, DELTA-SIGMA Czech. J. Phys., Vol.51, A345 d + A → n + … d + A → n + … P  4.5 GeV/c, I*pol.= 1.1.108 Line/setup: 1v(NBL) / PPT, DELTA-SIGMA Czech. J. Phys., Vol.52, C695 d + A → p + … P = 6.0; 9.0 GeV/c, I* 106 Line/setup: 6v / GIBS JINR Rap. Comm., 6[86]-97, p.61 a + A → t + … (*) -- per cycle at Pmax

10. Physics of Atomic Nuclei, v.66, 2003, p.1646

11. Beam by reactions 6Li + A  Nucleus + … Z=3 Z=2 Z=1 • Primary beam: • 6Li, t = 1.9 GeV/amu, (p = 2.67 GeV/c/amu ) • Intensity  5·107 nuclei/cycle (Synchr.) • Beam sizes on a target: sx< 4 mm, sy< 8 mm • Target: organic glass, 4.7 g/cm2 , at F5 Z/A=1/2 6Li • Secondary beam (4v line): • p/Z = 8.0 GeV/c (Z/A=1/3), • p/Z = 5.35 GeV/c (Z/A=1/2); • Intensity  104 nuclei/cycle (Z/A=1/3); d a Z/A=1/3 sy2 8 sy1 12.5 6He t QDC channels y1, mm y2, mm Vertical beam profiles at two positions before emulsion. Beam divergence relatively to the emulsion layers - sy< 2.5 mr Yields ratios, %: d:a = 51  3; 6He:t = 0.85  0.05

12. Fragment separation scheme: beam line layout f6 3v f5 VP-1 f4 VP-1 f3 Target: 5-8 g/cm2, polyeth. Extracted beams: 12C, 10B, 7Li

13. Fragment separation scheme: detector layout 2SP-40 S0 f5 sx= 6 sx= 12 • Multiwire ionization chambers (P9a, P10, P13, P13a, P14, P16 ) • Scintillation counter (Si)

14. Fragment separation: an optics scheme and realized resolution R=r16/Ex, r16 – linear dispersion, Ex= 2sx– envelope size Bars – normalized strengths of magnetic elements FWMHp/p  2.7% Distance along beam line, m

15. Secondary fragments beam: 10B + A 9Be + … Primary beam momentum: p0 = 2.0GeV/c/nucl. Energy losses spectrum in a plastics Z=5 (primary 10B mark) • Target: • Polyethylene, 8 g/cm2 • Placing – F3 focus • Separation scheme: • VP-1,f3 – f5 + 2SP-40, • j2SP-40 = 0.22r 4 ( 9Be ) • Analyzer: • Plastic scintillator, d=5mm Counts 3 • 9Be fraction in the beam: • 67 ± 2 % 2 QDC channels

16. Secondary fragments beam: 12C + A 9C + … ( p0 = 2.0GeV/c/nucl ) Energy losses spectrum in a plastics Counts Z6 51% C 3He QDC channels

17. Secondary fragments beam: 10B + A  8B + … (p0 = 2.0GeV/c/nucl) Energy losses spectrum in a plastics Z5 62% Counts 8B 3He 7Be 10C QDC channels

18. Secondary fragments beam: 7Be Production reaction: 7Li + A  7Be + … 7Be atom – T1/2 53.4d (e-cap.) 7Be nucleus – stable Beam rejection variant 1 Y4:Y1+2+3 1:3.3 1 2 7Be Beam rejection variant 2 Y4:Y1+2+… 1.9:1

19. 7Be fragmentation channels N.G. Peresadko et al., arXive:nucl-ex/0605014 v1

20. Conclusion Nuclotron accelerator facility flexibly provides experiments with a wide set of primary nuclei beams (p … Fe) in the energy range from hundreds MeV to several GeV per nucleon. In-flight production of secondary relativistic nuclear fragment beams are widely practiced at the facility. Secondary beams of the beryllium, boron and carbon isotopes were recently formed to study the nuclei clustering by the nuclear emulsion method.

21. End

22. Relativistic tritium beam Production reaction: a + A  t + X Beam profiles • Triton momentum – 6GeV/c • Momentum spread (s) – 1.6 % • ( TOF tagging was used) • Yeild at the line end – 510-3 Ia • @ Target – polystyrene, 5 g/cm2 • pa = 8GeV/c ( Ia  109 ppc) sx  10 sy  10 Target x, mm y, mm Momentum distribution sd 1.6 Beam line scheme: D1..6 – quadrupole doublets, M1..3 – bending magnets, GIBS – setup. TOF base78m. Ref.: S.A. Avramenko et al., JINR Rap. Comm., 6[86]-97, p.61; S.A. Avramenko et al., Nucl. Phys. A 596, p.355 dp, %

23. Beam by reactions 6Li + A  Nucleus + … Optics scheme and detectors layout 6Li Emuls.