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FLAR project
S.L. Yakovenko
JINR, Dubna,Russia
2
Contents
1.FlAIR project
2.AD facility at CERN
3.Antyhydrogen and Positronium in-flight at FLAIR
4.LEPTA facility
5.Experimental program
1.FlAIR project
3
1.FLAIR project (Contnd)
FLAIR - Facility for Low-energy Antiproton and Ion Research
4
L
5
1.FLAIR project (Contnd)
LSR- CRYRING
6
2.AD facility at CERN
Antiproton Decelerator (AD) typically supplies experiments with 25-30 million antiprotons with an energy of about 5 MeV in shots lasting approximately 200 ns every 100 s
7
The Antiproton Catching Trap
2.AD facility at CERN
8
The positron accumulator
(ATHENA – ALFA experiment )
2.AD facility at CERN
9
The ATHENA Mixing Trap
2.AD facility at CERN
10
The ATHENA Detector
2.AD facility at CERN
11
The ALPHA apparatus
2.AD facility at CERN
12
3. Antyhydrogen and Positronium in-flight at FLAIR
13
o-Ps
PCSR
3. Antyhydrogen and Positronium in-flight at FLAIR (Contnd)
General Parameters of the PCSR
14
Circumference m 10 – 11 Length of the section for recombination and electron cooling of antiprotons
m 1.0
Total length HTotal m 3.0 Length of the section for electron cooling of positrons
m 2.0
Positron energy keV 2 – 2.7 Revolution period nsec ~ 500-600 Longitudinal magnetic field G 50 Major radius of the toroidal solenoids (Rbend)
m 1
Positron beam radius cm 0.5 Number of circulating positrons - 1108 Recombination section length m 1 Positron energy in the recombination section
eV 50
Positron density in the recombination section
cm-3 6105
Recombination rate per 1 antiproton
s-1 110-7
Residual gas pressure Тоrr 110-11 Positron beam life time sec 100
Electron cooling system Length of cooling section m 1 Beam current A 0.1 Beam radius cm 1 Electron temperature meV 0.1
3. Antyhydrogen and Positronium in-flight at FLAIR (Contnd)
15
septum
kicker
cooling section
Ps detector
positron
trap
4. LEPTA Facility
22Na10E6
e+ per sec
10 6100sec=10 8 e +
10E4 Ps per sec
e-gun
collector
Helical quadrupoleO-Ps
16
Project Parameters of The LEPTACircumference , m 17.2
Positron energy, keV 2 10.0
Revolution time, ns 300
Longitudinal magnetic field, G 400
Average radius of the toroidal magnets, m 1.45
Helical quadrupole gradient, G/cm 10.0
Positron beam radius, cm 0.5
Number of positrons in the ring 1108
Residual gas pressure, Тоrr 110
Positronium beam parameters
Intensity, atom/s 110
Angular spread, mrad 1
Velocity spread 1104
Beam diameter at the exit of the ring, cm 1.1
4. LEPTA Facility (Contnd)
17
First beam circulation
Signals from vertical PU electrodes
10 September, 2004
Helical quadrupole off
0.5 μs/div
Helical quadrupole on
1.0 μs/div
4. LEPTA Facility (Contnd)
18
Tracing the ring with pencil beam (September - October 2007)
Electron gun
October 5, 2007
4. LEPTA Facility (Contnd)
19
1-positron source 22Na, 2-radioactive protection shield, 3-vacuum valve, 4-vacuum chamber for pumping out and diagnostic tools, 5-positron trap, 6 – vacuum isolator, 7 – positron vacuum channel, 8 – vacuum “shutter” (fast valve), 9 - ion pump, 10-turbopump, 11 –LHe vessel
The Positron Injector
4547 1 2
9 9 10
38
11
6LEPTA entrance
4. LEPTA Facility (Contnd)
20
Design parameters of the positron injector
Length, m 6,2
Positron injection energy, keV 10.0
Longitudinal magnetic field, G 400
Longitudinal magnetic field in the trap, G 1500
Residual gas pressure, Tor 1109
Beam radius, cm 0.5
Accumulation time, s 100
Injection pulse duration, ns 300
Number of positrons in injection pulse 1108
Positron momentum spread 110-4
4. LEPTA Facility (Contnd)
The Cryogenic Moderator of Positrons
22Na
Ne
e+
Ne
T ~ 5 K
0.8 MBqe+
e+
4. LEPTA Facility (Contnd)
22
The Cryogenic Positron Source
4. LEPTA Facility (Contnd)
23
Slow Positron Flux Formation
06.12.05 – First slow positron has been registered.April 2006 - moderator parameters optimization
The positron spectrum at the e+ flux of 5.3*103 positrons per sec of the average energy of 1.2 eV at the width of 1 eV was obtained. The moderator efficiency is 1 %.
Зависимость выхода позитронов от толщины замедлителя
0200400600800
100012001400160018002000
0 15 30 45 60 75 90 105 120 135 150
d, мкм
N/c
ек
Slow Positron Yield vs Frozen Neon Thickness
0 30 60 90 120 150
d, mcm
2000
1600
1200
800
400
0
Ncounts/sec
Slow positron spectrum dependence on frozen neon thickness
0
2000
4000
6000
8000
10000
12000
14000
16000
0,00 0,50 1,00 1,50 2,00 2,50 3,00 3,50 4,00
E, eV
dN
/dE
130мкм
90мкм
50мкм
30мкм
0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
Epos, eV
Slow Positron Spectrum vs Frozen Neon Thickness
16000
12000
8000
4000
0
dN/dE
4. LEPTA Facility (Contnd)
24
I II III IV V VIIVI
10-3
Pressure, Torr
N2 N2 е+
10-4 10-6
“Surko Trap”
Area 1 Area 2 Area 3 eU
z
4. LEPTA Facility (Contnd)
25
e-
0
-30
-60
I IIIII IV V VI VII VIII
-100 0
-29.3 -36.1-40.2-46.7
50.3 eV Electron storage studies
-50.3 V
-52.7 V
-90
4. LEPTA Facility (Contnd)
26
Rotating Electric Field Method
1800
00 900
2700
Phase filter
B
-U(x)
(а)
(b)
(c)
Generator
One electrode is placed under combined
alternative + permanent potentials (Fig.a, b, c).
4. LEPTA Facility (Contnd)
27
Rotating Electric Field Method (Contnd)
Зависимость числа накопленных электронов от времени накопления
0,00E+00
1,00E+07
2,00E+07
3,00E+07
4,00E+07
5,00E+07
6,00E+07
7,00E+07
8,00E+07
9,00E+07
0 10 20 30 40 50 60 70 80
t, сек
N
1 2 3
Stored electron number vs time
Aligniment of the axie of longitudinal magnetic and electric fields has been madeSame + rotating field is ON and optimized
Pressure distribution and potential are optimized
Optimal frotating = 650 kHz,
Amplitude = 1 V,
ε = 0.4, life = 25 s
April , 2007
life = 80 s, (Ne)max = 2108
4. LEPTA Facility (Contnd)
28
Experiments with Positrons and Positronium in flight at LEPTA
1.“Atomic” physics: e+e- recombination with positronium formation2. QED test in measurement of para-Positronium (p-Ps) life time 3. Test of CPT theorem, CP and P conservation:
3.1. Rare and forbidden decay channels of o-Ps3.2. Rare and forbidden decay channels of p-Ps3.3. Search for circularly polarized photons in p-Ps => 3.4. Measurement of the electron and positron charge difference upper limit
4. QED test in Ps spectroscopy4.1. Hyperfine structure of Ps ground state4.2. Spectroscopy of excited states, Lamb shift
5. Search for the Axion6. o-Ps life time and the hypothesis of “The Mirror Universe"7. Antihydrogen generation in-flight8. o-Ps in solid state physics9. Condensed matter physics research at the LEPTA positron injector10. Particle beam physics and accelerator technology
7. Antihydrogen generation in-flight
5. Search for the Axion 6. o-Ps life time and the hypothesis of “The Mirror Universe"
4. LEPTA Facility (Contnd)
29
The positron spectrum at the e+ flux of 1.5*105 positrons per sec of the average energy of 3 eV was obtained in the first experiments
New positron source activity of 25 mCi for LEPTA facility is under testing
Year 20094. LEPTA Facility (Contnd)
• Precision spectroscopy of antiprotonic atoms and antihydrogen for tests of fundamental interactions and symmetries (especially CPT)
• Interaction of Antimatter with Matter
• Nuclear and Particle Physics with Antiprotons
30
5.Experiment Research Program
31
Thank you for your attention!
- The FLAIR facility will drastically improve the conditions for the low energy antiproton research. First of all the beam intensity will be increased by about two orders of magnitude and the lower energy available allows a much more efficient use of the antiprotons compared to the AD operation.
- In-flight generation of antihydrogen might give rise to a number of very interesting experiments with relatively large number of antihydrogen particles. In particular the investigation of matter - antimatter reactions would become directly accessible in an interesting energy regime without the need of prior trapping of the particles.
6. Conclusion