PowerPointPrsentation

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Range of charged particles
(E. Segrè, Nuclei and particles)
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Alpha-particles in air (discovery of the
proton) (E. Segrè, Die großen Physiker...)
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Bragg curves (E. Segrè, Nuclei
and particles)
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Range of charged particles (aus C. Grupen,
Teilchendetektoren)
Muons in rock
Electrons in various materials
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Energy loss of charged particles due to ionisation
Bethe Bloch formula
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Energy loss of various charged particles in air
(C. Grupen, Teilchendetektoren)
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Energy loss of minimum ionising particles
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Contributions to the energy loss of muons in iron
(C. Grupen, Teilchendetektoren)
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Multiple scattering of electrons (W.R. Leo,
Techniques...)
Beam broadening
Backscattering
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Books on particle detection
G. Knoll Radiation detection (Addison
Wesley) W.R. Leo Techniques for nuclear and
particle physics experiments, a how-to
approach (Springer) C. Grupen Teilchendetektoren
(B.I. Wissenschaftsverlag)
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Cherenkov - Effect
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Cherenkov-radiators
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RICH1Ring Imaging Cherenkov

• 80 m3 (3 m C4F10)
• 116 VUV mirrors (3.3 m focal length)
• 5.3 m2 VUV detectors
• MWPC CsI photon-sensitive cathodes
• 8x8 mm2 pads
• 84k channels of analog
• read-out

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RICH-1
an event from on-line display
Photon detectors (PD) MWPCs with CsI
photocathodes (5.3 m2), 84,000 analog
read-out ch.s
VUV mirror wall, 21 m2, 116 mirrors
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Hadron reconstruction without and with RICH
Decay N ? K K-
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4. Particle interaction with condensed matter,
particle detection

• 4.1 Charged particles
• 4.1.1 Basic terms
• 4.1.2 Bethe-Bloch formula
• 4.1.3 Cherenkov effect
• 4.2 Photons
• 4.3 Neutrons
• 4.4 Some practical devices

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Photons in lead (C. Grupen, Teilchendetektoren)
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Neutrons
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Ionisation chamber (Grupen, Teilchendetektoren)
1 electron ion pair per w ? 30eV
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Yield of ions in a gas detector (Leo,
Techniques...)
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Multiwire chamber (Charpak) ? position
sensitivity (Grupen, Teilchendetektoren)
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Gas Electron Multiplier foils

• (Sauli 1995)

50 mm
(two dimensional)
2 dimensional read-out
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Organic Scintillator (Leo, Techniques...)
lt 10 ps
ns
Very rapid fluorescence signal (a few ns) ?
timing Production of light requires 100 eV per
photon (NaI 25 eV)
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Scintillator light guide photomultiplier (Leo,
Techniques...)
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Measurement of time-of-flight (Grupen,
Teilchendetektoren)
e.g. also as a veto detector
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Photomultiplier tube (Grupen, Teilchendetektoren)
Quantum efficiency of the photocathode 10 30
Amplification up to 107
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Multichannel plate (Application light
amplifiers) (Leo, Techniques...)
Channel width 10 100 ?m Amplification 103
104 per plate
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Energy resolution NaI-Scintillator Germanium
(Leo, Techniques...)
NaI 8 (25 eV per photon) Ge
0.15 (3 eV per photon)
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Bubble chamber (Glaser 1952)
- liquid at 5 20 atmospheres - bubbles form
along the path of ionisation at relaxation take
photo - magnetic field for deviation of charged
particles
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Hadronic Cascade (Grupen, Teilchendetektoren)
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