Quantum physics: illusion or reality?
In 1935 Albert Einstein, Boris Podolsky and Nathan Rosen[1] published a paper (referred to now as the EPR paper) which brought into question the completeness of quantum mechanics. Their main concern was associated with the predictions that quantum mechanics made concerning the influence that two particles had on each other once they were physically separated outside their interaction range. This called into question the whole concept of external reality in the physical world. In an effort to make quantum theory more complete, the idea of hidden variables was investigated. In 1964, John Bell[2] showed that it was possible to identify an experimental test for deciding between conventional quantum mechanics, with its holistic view of reality, or a theory that was based on a more localised concept of reality. The idea behind the project is to undertake such an experimental test using two correlated gamma-rays from the annihilation of a positron emitted by a Na22 radioactive source.[1] A.Einstein, B.Podolsky and N.Rosen, 'Can Quantum-Mechanical description of physical reality be considered complete?', Phys. Rev. 47, 777 (1935) doi
[2] J.S.Bell, 'On the Einstein-Podolsky-Rosen paradox', Physics 1, 195 (1964) doi and reproduced as paper 2 in J.S.Bell, 'Speakable and Unspeakable in Quantum Mechanics', Second Edition (2004), Cambridge.
Project notes (prepared by Professor Alan C.Shotter) PDF
II. Interaction of gamma radiation with matter, C.M.Davisson, Alpha, Beta & Gamma-Ray Spectroscopy, Ed. K.Siegbahn, North-Holland Publishing Co. Amsterdam 1965 PDF XIX. Angular Correlations, H.Frauenfelder and R.M. Steffen, Alpha, Beta & Gamma-Ray Spectroscopy, Ed. K. Siegbahn, North-Holland Publishing Co. Amsterdam 1965 Murray Library QC771 Sie
Ortec AN34 Experiment 3: Gamma-ray spectroscopy using NaI(Tl) PDF Ortec AN34 Experiment 13: Gamma-gamma coincidence PDF
Schematic of electronics setup PNG Canberra 802 Scintillation Detector PDF Canberra 2007/2007P Photomultiplier Tube Base/Preamplifier PDF Brandenburg 477 High Voltage PSU PDF Ortec 416A Gate & Delay Generator PDF Ortec 418A Universal Coincidence PDF Ortec 427A Delay Amplifier PDF Ortec 551 Timing Single Channel Analyzer PDF Ortec 855 Dual Amplifier PDF Ortec 875 Counter PDF Ortec EASY MCA 2k/8k Channel Multichannel Analyser here Ortec MAESTRO MCA Emulation Sofware here
Projects: Two sets of project equipment are available. Students are normally expected to work in pairs (i.e. maximum of four students per semester)
Laboratory: JCMB 5306
Project supervisors: Professor Philip J.Woods (JCMB 8203) and Prof Thomas Davinson (JCMB 8205)
Laboratory Technician: Mr Peter Black (JCMB 5306)
Risk Assessment: doc
Angular Correlation of 60Co
Many of the spin assignments of nuclear states which are currently known have been determined using measurements of the angular correlation of decay radiation. For gamma-gamma angular correlation measurements, one gamma-ray detector is fixed and detects the first gamma-ray of a cascade of successive gamma-rays produced as a nucleus de-excites to its ground state. The second gamma-ray detector is movable and detects the second gamma-ray of the cascade. The rate of coincidences between the two detectors as a function of the angle between the detectors and radiation source is called the angular correlation W(theta)
W(theta) = a0 + a2 cos2(theta) + a4 cos4(theta).
The objective of this project is to obtain a high precision measurement of the angular correlation of 1.17MeV and 1.33MeV gamma-rays in the decay cascade following the beta decay of 60Co to the 2.51MeV state of 60Ni to determine the parameters a0, a2, a4 and anisotropy. The project will require careful evaluation of possible systematic effects due for example, background radiation, gamma-ray summing, finite detector size
[1] Experiments in Modern Physics, A.C.Melissinos and J.Napolitano, Second Ed. (2003), Academic Press Available from the Murray Library (QC33 Mel)
[2] Ortec AN34 Educational Experiments, Third Edition, experiments 3, 13 & 19
Ortec AN34 Experiment 3: Gamma-ray spectroscopy using NaI(Tl) PDF
Ortec AN34 Experiment 13: Gamma-gamma coincidence PDF
Ortec AN34 Experiment 19: Angular correlation of 60Co PDF
Schematic of electronics setup PNG Canberra 802 Scintillation Detector PDF Canberra 2007/2007P Photomultiplier Tube Base/Preamplifier PDF Brandenburg 477 High Voltage PSU PDF Ortec 416A Gate & Delay Generator PDF Ortec 418A Universal Coincidence PDF Ortec 427A Delay Amplifier PDF Canberra 2037A edge Crossover SCA PDF Ortec 855 Dual Amplifier PDF Ortec 875 Counter PDF Ortec EASY MCA 2k/8k Channel Multichannel Analyser here Ortec MAESTRO MCA Emulation Sofware here
Projects: One set of project equipment is available. Students are normally expected to work alone.
Laboratory: JCMB 5306
Project supervisors: Professor Philip J.Woods (JCMB 8203) and Prof Thomas Davinson (JCMB 8205)
Laboratory Technician: Mr Peter Black (JCMB 5306)
Risk Assessment: doc
Last revised: 26.9.24