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13. Development of knowledge in high energy physics.¶
What are the structures of atomic nuclei and of elementary particles?
This is the first chapter dedicated to the Universe. It describes a selection of Nobel Prizes that have contributed to better understanding high energy physics (nuclear physics and particle physics). Such contributions are organized into three categories: the laboratory instruments, the experimental results, and the theorical approaches. Cosmology is considered in next Chapter 14.
Learning objectives of Chapter 13.¶
After this Chapter you should be able to:
- Describe the main instruments, laboratories and experimental settings employed in the study of high energy physics.
- Analyze the main experiments that contributed with critical observations and measurements in high energy physics.
- Consider the main theoretical approaches that fruitfully explained high energy physics.
Description of content of Chapter 13.¶
Section 13.1. Descriptions of laboratory instruments.
The most relevant devices and technological settings and installations used for research in high energy physics are considered.
Section 13.2. Accounts of experimental results.
The critical experiments made for answering relevant questions in high energy physics and the physical interpretations of their consequences are described.
Section 13.3. Contributions made by theoretical approaches.
The most successful cognitive structures serving to interpret, explain, and predict physical phenomena in high energy physics are reviewed.
13.1. Descriptions of laboratory instruments.¶
According to Piaget and García (1988) there are three levels of operation of the mechanisms of knowing: the level intra for the description of objects, the level inter for the transformation of concepts and the level trans for the construction of structures. We associate these levels of operation with three categories describing the contributions made by Nobel laureates working in high energy physics: the laboratory instruments, the experimental results, and the theorical approaches.
The selected contributions of the Nobel laureates are organized in terms of each one of the levels of operation of the mechanism of knowing that corresponds to instruments, results and approaches. In each level of operation, we group the Nobel Prizes into categories describing their main physics content. For each category a brief description of the included Prizes is presented on a table. It follows an image representing some aspect of the physics content of the category and then, the corresponding Nobel Prizes are described.
We identify each Nobel Prize with the shorthand of the discipline (Ph for Physics or Ch for Chemistry) and the year of the award. Afterwards, we quote a Nobel document called WORK describing the contribution of each laureate. The title of the corresponding Nobel Lecture is also included. The name of each laureate leads to a hyperlink containing biographical information. All the references to Nobel documents are given in MLA format.
The laboratory instruments.¶
(Source: Wikipedia common)
Figure 13.1. Original apparatus created by Röntgen and by Lawrence.
Ph1901 to Wilhelm Conrad Röntgen “in recognition of the extraordinary services he has rendered by the discovery of the remarkable rays subsequently named after him”.
WORK: “In 1895, Wilhelm Röntgen studied cathode radiation, which occurs when an electrical charge is applied to two metal plates inside a glass tube filled with rarefied gas. Although the apparatus was screened off, he noticed a faint light on light-sensitive screens that happened to be close by. Further investigations revealed that this was caused by a penetrating, previously unknown type of radiation. X-ray radiation became a powerful tool for physical experiments and examining the body's interior.”
MLA style: Wilhelm Conrad Röntgen – Facts. NobelPrize.org. Nobel Prize Outreach AB 2023. Sat. 23 Dec 2023. https://www.nobelprize.org/prizes/physics/1901/rontgen/facts/
No Nobel Lecture was delivered.
Ph1939 to Ernest Orlando Lawrence “for the invention and development of the cyclotron and for results obtained with it, especially with regard to artificial radioactive elements”.
WORK: “If the nuclei of atoms are bombarded by beams of particles, such as protons, the atoms can be transformed into different variants of the element with different masses, so-called isotopes. The likelihood that particles can penetrate the atomic nucleus and bring about a nuclear reaction increases if the bombarding particles have a high velocity. In 1929 Ernest Lawrence developed an apparatus known as a cyclotron that used electrical and magnetic fields to accelerate protons to high velocities in a spiral-shaped path before they collide with their target.”
MLA style: Ernest Lawrence – Facts. NobelPrize.org. Nobel Prize Outreach AB 2023. Mon. 17 Jul2023. https://www.nobelprize.org/prizes/physics/1939/lawrence/facts/
NOBEL LECTURE: The Evolution of the Cyclotron by Lawrence.
MLA style: Nobel Lecture. NobelPrize.org. Nobel Prize Outreach AB 2023. Mon.17Jul2023. https://www.nobelprize.org/prizes/physics/1939/lawrence/lecture/
Ph1950 to Cecil Frank Powell “for his development of the photographic method of studying nuclear processes and his discoveries regarding mesons made with this method”.
WORK: “Charged particles moving through photographic emulsions leave tracks that can be examined in the images developed afterward. Cecil Powell made improvements to this technique in order to study radiation and nuclear reactions. In 1947 he discovered that incident cosmic ray particles could react with atomic nuclei in the emulsion, creating other, short-lived particles. These particles turned out to be pi-mesons, the particles proposed by Yukawa as mediating the strong force binding protons and neutrons in nuclei.”
MLA style: Cecil Powell – Facts. NobelPrize.org. Nobel Prize Outreach AB 2023. Thu. 3 Aug 2023. https://www.nobelprize.org/prizes/physics/1950/powell/facts/
NOBEL LECTURE: The Cosmic Radiation by Powell.
MLA style: Cecil Powell – Nobel Lecture. NobelPrize.org. Nobel Prize Outreach AB 2023. Thu. 3 Aug 2023. https://www.nobelprize.org/prizes/physics/1950/powell/lecture/
(Source: Wikipedia common)
Figure 13.2. Original cloud chamber created by Wilson and track of an alpha particle obtained in a diffusion cloud chamber.
Ph1927 to Charles Thomson Rees Wilson “for his method of making the paths of electrically charged particles visible by condensation of vapour”.
WORK: “If the volume of a mixture of air and water vapor increases, small water drops form. If the air contains electrically charged particles—ions—then droplet formation occurs around these especially. C.T.R. Wilson exploited this phenomenon when he constructed his cloud chamber in 1911—a glass container with air and water vapor and ingenious devices that allow traces left by ionizing radiation and particles that pass through the chamber to become visible and be photographed. The cloud chamber became an important tool in physics.”
MLA style: C.T.R. Wilson – Facts. NobelPrize.org. Nobel Prize Outreach AB 2023. Wed. 28 Jun 2023. https://www.nobelprize.org/prizes/physics/1927/wilson/facts/
NOBEL LECTURE: On the Cloud Method of Making Visible Ions and the Tracks of Ionizing Particles by Wilson.
MLA style: C.T.R. Wilson – Nobel Lecture. NobelPrize.org. Nobel Prize Outreach AB 2023. Mon. 17 Jul 2023. https://www.nobelprize.org/prizes/physics/1927/wilson/lecture/
Ph1960 to Donald Arthur Glaser “for the invention of the bubble chamber”.
WORK: “Our ability to study the smallest components of our world took a giant leap forward when C.T.R. Wilson invented the cloud chamber, where the trails of charged particles can be observed. Donald Glaser's invention of the bubble chamber in 1952 made it possible to study particles with higher energies. When charged particles rush forward through the chamber filled with a liquid at near-boiling point, they ionize atoms they pass by. When the pressure inside the chamber is then reduced, bubbles form around these charged atoms. The particles' tracks can then be photographed and analyzed.”
MLA style: Donald A. Glaser – Facts. NobelPrize.org. Nobel Prize Outreach AB 2023. Mon. 17 Jul 2023. https://www.nobelprize.org/prizes/physics/1960/glaser/facts/
NOBEL LECTURE: Elementary Particles and Bubble Chambers by Glaser.
MLA style: Donald A. Glaser – Nobel Lecture. NobelPrize.org. Nobel Prize Outreach AB 2023. Mon. 17 Jul 2023. https://www.nobelprize.org/prizes/physics/1960/glaser/lecture/
Ph1992 to Georges Charpak “for his invention and development of particle detectors, in particular the multiwire proportional chamber”.
WORK: “When onrushing particles collide and form showers of new particles, they offer a key to understanding the smallest components of matter. In 1968 Georges Charpak developed the multiwire proportional chamber, which represented a more effective way of detecting particles. The multiwire chamber contains many parallel metal wires surrounded by a gas. Between the chamber’s walls and the threads, an electrical charge is introduced. When particles enter, electrons in the gas are liberated in cascading fashion. Currents are generated in the wires and are registered and processed using computers.”
MLA style: Georges Charpak – Facts. NobelPrize.org. Nobel Prize Outreach AB 2023. Mon. 17 Jul 2023. https://www.nobelprize.org/prizes/physics/1992/charpak/facts/
NOBEL LECTURE: Electronic Imaging of Ionizing Radiation with Limited Avalanches in Gases by Charpak.
MLA style: Georges Charpak – Nobel Lecture. NobelPrize.org. Nobel Prize Outreach AB 2023. Mon. 17 Jul 2023. https://www.nobelprize.org/prizes/physics/1992/charpak/lecture/