LabBTheCreationandAnnihilationofAntimatter.pptVIP

Lab B4: The Creation and Annihilation of Antimatter SFSU Physics 490 Spring 2004 Professor Roger Bland Lab Partners Yvette Martinez Michael Hoffman Elizabeth Manrao Experiment Description In this experiment you can observe evidence for production and absorption of gamma and beta rays, and for the creation and annihilation of antimatter! Processes involving gamma rays will be interpreted using Feynman diagrams. Learning Goals Understand the sodium-iodide scintillation detector. Learn how a pulse-height analyzer works. Learn the different ways in which gamma rays interact with matter. Understand the energy-level and decay schemes for cobalt-60. 3 Ways Gamma Rays Interact The Photo-Electric Effect Compton Scattering Pair Production The Photo-Electric Effect Definition: The emission of an electron from a surface as the surface absorbs a photon of electromagnetic radiation. Electrons so emitted are termed photoelectrons. Source: /dictionary/p.html? Compton Scattering Definition: The scattering of photons from charged particles is called Compton scattering after Arthur Compton who was the first to measure photon-electron scattering in 1922. Source: /vvc/glossary.html Pair Production Definition: An absorption process for X-ray and gamma ray radiation in which the incident photon is annihilated in the vicinity of the nucleus of the absorbing atom, with subsequent production of an electron and positron pair. Source: /~dglover/dictionary/p.html? Experimental Procedure Equipment List Tracerlab Detector #45292 Computer: Halley 2 (IP 6) Oscilloscope: SN# dual trace Canberra 816 Amplifier High Voltage Power Supply #70501 Radioactive sources: Co-60, Cs-137, Na-22 Experimental Procedure Diagram of Apparatus NaI Scintillation Detector Scintillation detectors detect light emitted by electrons when they change energy levels. We use ionizing radiation from radioactive sources to provide the electrons sufficient energy to move into a higher e