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Anmerkungen
Lieber Herr Giessgen,ich füge hier in ROT ein paar Anmerkungen undKorrekturen an.Ich rate, besser linksbündigen Textsatz zu verwenden, da er erheblich besserlesbar ist.
Proseminar: Understanding the Universe
Particle Detectors
Tom Gießgen
04/11/23 proseminar: understanding the universe 3
outline
1. Introduction
2. Interaction with matter
3. Particle detectors in general
4. Semiconductor detector
5. Sources (besser: Literature)
04/11/23 proseminar: understanding the universe 4
1. Introduction orWhy do we need particle detectors?
experiments in elementary particle physics:when particles are accelerated and collide,
detectors provide information about reaction_products-> conclusion about (! explanation of) actual process
for example at CERNvery (highly) complex (systems of) detectors: ALICE, ATLAS, CMS, ...
source: http://www.kennislink.nl http://www.kip.uni-heidelberg.de
04/11/23 proseminar: understanding the universe 5
detecting cosmic radiation and neutrinos
Super-Kamiokande in Japan
http://www.hep.shef.ac.uk
04/11/23 proseminar: understanding the universe 6
other applications:
CT, PET, MRT, X-Ray C-14 method
measurement of ionizing radiation(-> radioprotection)
PET
http://de.wikipedia.org
geiger müller counter
04/11/23 proseminar: understanding the universe 7
searching for unkown chambers in the Chephren-pyramid
by measuring the intensity of muons
Sehr schönes Beispiel! Wichtig ist, dass Sie den Detektor und die Höhenstrahlung einzeichnen. Vielleicht auch ein Resultat?
04/11/23 proseminar: understanding the universe 8
2. interaction with matter
charged particles interact mainly with electrons: stimulation (! Excitation) Ionization Coulomb scattering
other effects: Bremsstrahlung Coulomb scattering off the nucleus
uncharged particles interact with atomic matter (Photo effect, Compton effect) first and than create charged particles
04/11/23 proseminar: understanding the universe 9
Energy-loss of particles is described by Bethe-Bloch formula:
~
z charge of the particleZ,A charge and mass number of detector matter
I value depending on matterbeta, gamma velocity and Lorentz_factor
C constant
−dEdx
Z z²Abeta²
ln I gamma² beta² −beta²−C
Achtung! Nicht lesbar!
Kleine Liste mit A:B:C:D:
04/11/23 proseminar: understanding the universe 10
minimal ionization occurs when βγ ≈ 4
mean energy loss for MIP
absorber
H2
4.12O
21.82
Al 1.62Si 1.66Fe 1.48Pb 1.13
−dEdx
in MeVg / cm²
dE/dx * rhoin MeV / cmnoch hinzufügen
04/11/23 proseminar: understanding the universe 11
3. Particle detectors in generalparticles: free molecules, atoms or elementary particles
there are detectors for measuring:
ionization and traceionization_chamber, Geiger-Müller Tube-
tube momentum
magnetic spectrometer time
scintillator (! scintillation) detector energy
semiconductor detector, calorimeter
04/11/23 proseminar: understanding the universe 12
4. Semiconductor detectors
basically a (reverse biased) p-n-semiconductor diode
Si or Ge as semiconductor
http://ocw.weber.edu
04/11/23 proseminar: understanding the universe 13
http://nsspi.tamu.edu
semiconductor detector with incoming particle
Gut erklären! Hier kommt es auf das bleibende Verständnis an.
04/11/23 proseminar: understanding the universe 14
advantages: particles with high energy can be stopped less energy for creating electron-hole-pair required short time response simple installation
disadvantages: must be cooled (especially Germanium) small detector volume -> p-i-n semiconductor
04/11/23 proseminar: understanding the universe 15
applications of semiconductor detectors
energy measurement
number of charge carriers is proportional to deposited energy
tracking particles
electrodes are stripes on the semiconductor-> 1-dim local information
http://wwwa1.kph.uni-mainz.de
04/11/23 proseminar: understanding the universe 16
6. Sources (!Literature)
Teilchendetektoren, Claus Grupen, Wissenschaftsverlag 1993
The Particle Detector Briefbook, R. Bock, A. Vasilescu, Springer Verl. 1998
Physik, Paul Tipler, Akademischer Verlag 1994
wwwa1.kph.uni-mainz.de/Vorlesungen/WS08/FP-Seminar/handouts/KP06_Wanka.pdf