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Explore the intriguing story of cold fusion, the controversial announcement on March 23, 1989, and the subsequent scientific scrutiny. Delve into the fusion reactions, experimental setup, evidence, media frenzy, confirmations, doubts, retractions, and the ultimate outcome of this groundbreaking but disputed discovery.
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Too Good To Be True The Strange, But True, Story of Cold Fusion
The Announcement • March 23, 1989 – Salt Lake City • “Two scientists have successfully created a sustained nuclear fusion reaction at room temperature in a chemistry laboratory at the University of Utah.” • “The greatest invention since the discovery of fire.”
Pons and Fleischmann Dr. Stanley Pons Dr. Martin Fleischman
p n A Nuclear Fusion Primer • In nuclear fusion two light nuclei are combined into a heavier nucleus, releasing energy. • Deuterium, 2H, can be used in D-D fusion to release approximately 4.00 MeV per fusion. Deuterium
p p p p n n n n p n n n p p 3H 3He p n Two Pathways D + D p + 3H D + D n + 3He
Energy Of Fusion • In the D + D p + 3H reaction most of the energy (3 MeV) is carried away by the proton. • In the D + D n + 3He reaction the neutron carries most of the energy (2.45 MeV).
Hot Fusion • Because of the electrostatic repulsion between the deuterium nuclei high temperatures are used to bring them together to fuse. • Magnetically confined plasmas are used to generate the high temperatures.
The Cold Fusion Machine • The Cold fusion “machine” was a beaker of “heavy water” (D2O) with a couple of electrodes and a small power supply.
The Cold Fusion Experiment How did they do that?
The Cold Fusion Cell • The anode is a coil of platinum and the cathode a palladium rod. • The cell is filled with heavy water and immersed in a water bath. • LiOD is added to the heavy water as the electrolyte.
The Cold Fusion Process • The electric current splits the D2O molecules into D2 gas and OD– ions at the cathode. • The ions migrate to the anode and form D2O and O2. • Palladium has a great affinity for hydrogen and deuterium ions are absorbed into the cathode – up to a density of thousands of times that of deuterium gas. • The closely packed deuterium nuclei fuse and release heat, neutrons, protons, etc.
The Signs of Fusion • Excess Heat* • Neutrons* • Tritium* (?) • 3He • Protons
The P & F Evidence Heat and Light
Neutrons via Gammas • Some neutrons would be absorbed by the H nuclei in the water releasing a 2.2 MeV gamma- ray. • P & F looked for these gammas.
Gamma-Rays • The gamma-ray peak as presented in the first P & F paper submitted to the Journal of Electroanalytical Chemistry (JEC).
The Reaction Men, it has been well said, think in herds; it will be seen that they go mad in herds, while they only recover their senses slowly, and one by one. -Charles Mackay Extraordinary Popular Delusions and the Madness of Crowds,1841
A Media Explosion • Cold Fusion became a instant media event. • P & F were interviewed on all the major news networks. • Congress scheduled hearings on CF.
The Scramble to Confirm or Refute • Numerous physics and chemistry labs began experiments using the limited information available. • Large scale efforts at MIT, Los Alamos, Harwell, Yale, and Caltech were launched.
Confirmations • Jones, et. al. (BYU Neutrons) • Georgia Tech – Neutrons • Texas A & M – Excess Heat • Seattle – Tritium • Small colleges and independent researchers • Bob’s Discount House of Knowledge
Doubts • Why are they still breathing? • Heat vs. neutron output. • Are the nuclei really any closer? • Where are the control runs? • What’s wrong with that peak? • The MIT gang goes to the video replay.
Gamma-Rays • The gamma-ray peak as presented in the first P & F paper submitted to the Journal of Electroanalytical Chemistry (JEC). 2200
The APS Meeting • Caltech: Steve Koonin and Nathan Lewis • Questions about the Calorimetry • Closed cell vs. Open cell • Raw data? • A lot of negative results.
Retractions • Georgia Tech – Temperature (not Neutrons) • Texas A & M – Ungrounded thermistor (not Excess Heat ) • Seattle – “Remind me how a mass spec works again.” (not Tritium )
Harwell • Working with advice from Fleischmann the Harwell Nuclear Lab conducted the most extensive set of cold fusion tests in the world. • Cells were tested in numerous configurations for heat, neutrons, gammas, tritium, and Helium-3. • No evidence for nuclear processes in any of the experiments. • “Sometimes brilliant people have mad ideas” – J. Williams, Dir. Harwell Lab
The Utah Physicists • Mike Salamon lead a team of physicists from the University of Utah to make extensive radiation measurements in Pons’ laboratory. • Na(I) detectors searched for Gamma-rays from neutrons, and protons. • No signal was seen above background after 831 hours of measurement. • “upper bound of 10 picowatts of energy generated by any known nuclear process”
What Happened? And what can we learn?
Pons & Fleischmann • Was it a fraud? • The rush to announce. • “The explosion.” • Isolation from peers. • “Sometimes brilliant people have mad ideas.”
The Science Community • Meeting expectations. • The good, the bad and the normal distribution. • “Seek simplicity, and distrust it” A. N. Whitehead