xviii international baldin seminar on high energy physics problems "relativistic nuclear...
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XVIII International Baldin Seminar on High Energy Physics Problems"RELATIVISTIC NUCLEAR PHYSICS & QUANTUM CHROMODYNAMICS“
Dubna, September 27, 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 EnergiesJoint Institute for Nuclear Research
Supported by Russian Foundation for Basic Research ( 04-02-17151 )
LHE Accelerator Facility
Polaris – d
EBIS – N, Ar, Fe …Laser – Li, B, C, F, Mg …Duoplasmotron – p, d, , 3He
Internal target
Experimental hall 1B
Experimental hall 205
Experimental hall
NUCLOTRON – 6 GeV/n
SYNCHROPHASOTRON
BeamNuclotron beam intensity (particle per cycle)
Current Src. type Ion source devel. + booster*
p 51010 Duoplasmotron 11013
d 51010 --- # --- 11013
4He 3109 --- # --- 21012
d 2108 ABS (“Polaris”)
7Li 4109 Laser 51012
11,10B 1109,8 --- # ---
12C 2109 --- # --- 21012
24Mg 1108 --- # ---
14N 1107 ESIS (“Krion-2”)** 51011
24Ar 2107 --- # --- 2109
56Fe 1106 --- # ---
131Xe 2108
238U 1108
* A.V. Butenko et al., EPAC 2002
** E.D. Donets et al., Rev. Sci. Instr. 75, (2004)
Some Nuclotron beams
-32 -16 0 16 32 -32 -16 0 16 32
Y
Parameter @ Units Value
Extraction angle, hor./ ver. mr 5 / 96
Momentum range Z/A = 1/2 Gev/c/amu 0.6 – 6.8
Momentum spread, % 0.04 – 0.08
Extraction time sec 10
Beam emittance Pmax mmmr 2
Beam size in a waist, Pmax mm < 1
Extraction efficiency % > 90
Beam profiles at the F5 focus.
Deuterons, pbeam = 4.3 GeV/c, x = 2.6 mm, y = 3.0 mm
x, mm y, mm
Nuclotron slow extraction
V.Volkov et al., EPAC 2004An extracted beam spill (Nuclotron Dec. 2003 run)
f3
f4
f5
f6
VP-1
VP-1
1v
3v
3v
4v
4v
5v
Slowlyextracted beam
6v
Bending magnets
Quadrupole lenses
Dump, shield
Nuclotron external beam lines
Lines Pmax Imax
( GeV/c ) ( ppc )
• VP-1 15 1012
• 1v 9 10 8
• 3v 9 10 9
• 4v 9 10 7
• 5v 12 10 7
• 6v 12 10 7
MARUSYA
STRELA
GIBS
DELTA-SIGMA
FAZA
SPHERA
NIS
Polarized Proton Target
f3 experimental area
A0, Z0, p0 A0, Z0, p0 + (Ai, Zi, p0)0
A0, Z0
p0Ai/Zi
p0Ak/Zk
Primary beam
Target
Separation system Analyzingdetectors
Projectile fragments
Secondary relativistic fragments beams: a general scheme
0 0
Primary beam dump
Tagging detectors(option)
p0 -- projectile momentum per nucleon
Secondary relativistic fragment beams: relations
Fragment angular and relative momentum spread in the laboratory frame
Fragment momentum spread in the projectile rest frame
0 90 MeV/cA – projectile mass numberB – fragment mass number
A.S. Goldhaber, Phys. Lett. 53B, p.306
p0 – projectile momentum per nucl.
0 – 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.) :
7.5 mr, 1.8 %
Secondary relativistic fragment beams: rigidity scale neighborhood
Example: 10B 8B fragmentation
-25 -20 -15 -10 -5 0 5 10 15 20 25
3He
7Be
8B
(p-p0)/z, %
d + A → n + …
The lightest relativistic fragment beams
P 4.5 GeV/c, I*
pol. = 1.1 . 108
Line/setup: 1v(NBL) / PPT, DELTA-SIGMA
Czech. J. Phys., Vol.52, C695
P = 6.0; 9.0 GeV/c, I* 106
Line/setup: 6v / GIBS
JINR Rap. Comm., 6[86]-97, p.61
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
(*) -- per cycle at Pmax
d + A → n + …
d + A → p + …
+ A → t + …
Physics of Atomic Nuclei, v.66, 2003, p.1646
Beam by reactions 6Li + A Nucleus + …
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: x < 4 mm, y < 8 mm
• Target: organic glass, 4.7 g/cm2 , at F5
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);
-60 -40 -20 0 20 40 60 -60 -40 -20 0 20 40 60
y1, mm y2, mm
Vertical beam profiles at two positions before emulsion.Beam divergence relatively to the emulsion layers - y < 2.5 mr
y1 12.5
y2 8
40 50 60 70
20 30 40 50 60 70 80 90 100 110 120
20 30 40 50 60 70 80 90 100 110 120
Z=1 Z=2 Z=3
6Li
6He
t
QDC channels
Z/A=1/3
Z/A=1/2
d
Yields ratios, %:
d : = 51 3; 6He : t = 0.85 0.05
f3
f4
f5
f6
VP-1
VP-1
3v
Extractedbeams: 12C, 10B, 7Li
Target: 5-8 g/cm2, polyeth.
Fragment separation scheme: beam line layout
2SP-40
f5
Fragment separation scheme: detector layout
S0
-40 -20 0 20 40 -40 -20 0 20 40 -60 -30 0 30 60 -60 -30 0 30 60 -20 -10 0 10 20 -20 -10 0 10 20 -60 -30 0 30 60 -60 -30 0 30 60
-60 -30 0 30 60 -60 -30 0 30 60 -20 -10 0 10 20 -20 -10 0 10 20 -60 -30 0 30 60 -60 -30 0 30 60 -60 -30 0 30 60 -60 -30 0 30 60
• Multiwire ionization chambers (P9a, P10, P13, P13a, P14, P16 )
• Scintillation counter (Si)
x= 6 x= 12
Fragment separation: an optics scheme and realized resolution
Distance along beam line, m
R=r16/Ex, r16 – linear dispersion, Ex = 2x– envelope size
Bars – normalized strengths of magnetic elements
FWMHp/p 2.7%
100 150 200 250 300 350
0
200
400
600
800
Z=5 (primary 10B mark)
4 ( 9Be )
3
2
QDC channels
Counts
Secondary fragments beam: 10B + A 9Be + …
Target:• Polyethylene, 8 g/cm2
• Placing – F3 focus
Separation scheme:• VP-1, f3 – f5 + 2SP-40,
• 2SP-40 = 0.22 r
Analyzer:• Plastic scintillator, d=5 mm
9Be fraction in the beam:
• 67 ± 2 %
Primary beam momentum:
p0 = 2.0 GeV/c/nucl.Energy losses spectrum in a plastics
100 200 300 400 5000
100
200
300
400
C3He
Secondary fragments beam: 12C + A 9C + … ( p0 = 2.0 GeV/c/nucl )
Z6 51%
QDC channels
Energy losses spectrum in a plasticsCounts
0
50
100
150
100 150 200 250 300 350
Secondary fragments beam: 10B + A 8B + … (p0 = 2.0 GeV/c/nucl )
Z5 62%
8B
10C
7Be3He
QDC channels
Energy losses spectrum in a plasticsCounts
32 64 96 128 160 192 224 256
Chan.
0
1000
2000
3000
1
z=2
secondary spectraprimary Li-7 reper
3
3
4
Secondary fragments beam: 7Be
Production reaction: 7Li + A 7Be + …
Beam rejection variant 1
Y4 : Y1+2+3 1 : 3.3
50 100 150 200 250
Beam rejection variant 2
Y4 : Y1+2+… 1.9 : 1
7Be
1
2
7Be atom – T1/2 53.4 d (e-cap.)7Be nucleus – stable
0
5
10
15
20
25
30
35
3H
e +
4H
e
3H
e +
3H
e
4H
e+p
+p
4H
e+d
+p
3H
e+p
+p
3H
e+d
+p
3H
e+d
+d
3H
e+t+
p
p+
p+
p+
d
p+
p+
d+
d
6L
i+p
nb=0nb=1
7Be fragmentation channels
N.G. Peresadko et al., arXive:nucl-ex/0605014 v1
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.
End
-90 -60 -30 0 30 60 90 -90 -60 -30 0 30 60 90
x, mm y, mm
Beam profiles
Relativistic tritium beam
Production reaction: + A t + X
x 10 y 10
Beam line scheme: D1..6 – quadrupole doublets, M1..3 – bending magnets, GIBS – setup. TOF base 78 m.
Target
• Triton momentum – 6 GeV/c
• Momentum spread () – 1.6 % ( TOF tagging was used)
• Yeild at the line end – 510-3 I
@ Target – polystyrene, 5 g/cm2
p = 8 GeV/c ( I 109 ppc)
-15 -10 -5 0 5 10 15
Momentum distribution
1.6
p, %
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
Emuls.
Beam by reactions 6Li + A Nucleus + …
Optics scheme and detectors layout
6Li