The Polarized Internal Gas Target of ANKE at COSY

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The Polarized Internal Gas Targetof ANKE at COSY
Kirill Grigoriev Institute for Nuclear Physics
(IKP) Forschungszentrum, Jülich

• 16th International Spin Physics Symposium
• Trieste, Italy
• October 15, 2004

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Outline

• Introduction
• Atomic Beam Source
• Lamb-Shift Polarimeter
• Storage Cell prototypes
• Apertures test at COSY
• Outlook

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COSY ? COoler SYnchrotron

• COSY
• storage ring for polarized proton
• and deuteron beams
• with momentum range 600 - 3700 MeV/c
• COSY used for
• internal experiments - with the circulating
• beam (ANKE, COSY-11, EDDA, PISA)
• external experiments - with the extracted
• beam (BIG KARL, JESSICA, NESSI, TOF)

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ANKE at COSY

• Magnets
• D2 spectrometer magnet
• D1, D3 beam bending magnets
• Detector systems
• Positive Negative
• Forward Backward
• Spectator Detectors

• Targets
• Solid strip
• Cluster
• Polarized

Spectrometer ANKE
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PIT at ANKE

• Technical constraints
• Installation time of the PIT is
• limited to 3-4 days
• D2 is movable ? needs
• sophisticated supporting
• bridge between D1 and D2
• Tunnel width is limited
• ? 60 angle between LSP
• components
• ABS axis is 50 cm away from
• D2 yoke ? shielding from the
• stray field is needed

ABS
Storage cell
Polarimeter
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Stray field MAFIA calculation
60-90 G 135 G
35-45 G 300 G
30 G 55 G
30 G 55 G
200 G 300 G
5-6 G 30 G
50-60 G 300 G
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Laboratory Setup

• Setup at the laboratory consist of
• Atomic Beam Source
• Test chamber with storage
• cell prototype
• Lamb-Shift Polarimeter

Setup at the laboratory
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Atomic Beam Source
Working principle
H beam intensity 8.0x1016 at/s
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Lamb-Shift Polarimeter
Lamb-Shift Polarimeter layout
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ABS beam polarization measurements
Ly-a spectra of hydrogen and deuterium measured
with LSP
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PIT test setup
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ABS beam profile at cell
ABS beam
beam extracted from cell
beam extracted from cell
ABS beam ?
COSY beam
COSY beam
Storage cell prototype
Top view of beam profile on glass with molybdenum
oxide
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ABS beam profile
s 2.85 0.42
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Cell prototype
ABS beam

• ABS beam profile is known
• Target gas sample profile
• can be simulated if shapes of
• all tubes are known
• COSY beam profile should
• be analyzed

Target gas sample
COSY beam
Beams directions at storage cell
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Apertures tests at COSY
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Principle of the apertures tests at COSY
1. Beam in the center of
the aperture 50 mm
2. Aperture moves to the right until
intensity drops 5 mm
3. Aperture moves to the left until intensity
drops 11 mm
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Apertures tests at COSY
Tests with an accelerated beam
Tests at injection
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Estimated COSY-beam profile
36x16 mm 9x12 mm
16x15 mm
cluster target on (density 1014 at/s)
at injection
cluster target off
with an accelerated beam
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Time schedule
Before end 2004 transfer of ABS and LSP
to COSY hall Spring 2005 cell
prototype tests at ANKE with
unpolarized storage cell target Summer 2005
first installation of PIT at COSY,
commissioning and initial research After all
ready for all kinds of experiments
with Polarized Internal
Gas Target !!!
in progress approved to be scheduled