anmerkungen lieber herr giessgen, ich füge hier in rot ein paar anmerkungen und korrekturen an. ich...

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)


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


detecting cosmic radiation and neutrinos

Super-Kamiokande in Japan

http://www.hep.shef.ac.uk


other applications:

CT, PET, MRT, X-Ray C-14 method

measurement of ionizing radiation(-> radioprotection)

PET

http://de.wikipedia.org

geiger müller counter


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?


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


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:


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


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


4. Semiconductor detectors

basically a (reverse biased) p-n-semiconductor diode

Si or Ge as semiconductor

http://ocw.weber.edu


http://nsspi.tamu.edu

semiconductor detector with incoming particle

Gut erklären! Hier kommt es auf das bleibende Verständnis an.


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


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


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

anmerkungen lieber herr giessgen, ich füge hier in rot ein paar anmerkungen und korrekturen an. ich...

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