General Physics (PHY 2140) General Physics (PHY 2140) Lecture 20. Lecture 21. Previously. Processes of Nuclear Energy. Fission.
|
|
- John Melton
- 5 years ago
- Views:
Transcription
1 General Physics (PHY 2140) Lecture 20 Modern Physics Nuclear Energy and Elementary Particles Fission, Fusion and Reactors Elementary Particles Fundamental Forces Classification of Particles Conservation Laws Chapter 30 Chapter 29 General Physics (PHY 2140) Lecture 21 Modern Physics Elementary Particles Strange Particles Strangeness The Eightfold Way Quarks Colored Quarks Electroweak Theory The Standard Model The Big Bang and Cosmology Chapter 30 Chapter 29 Nuclear Physics Nuclear Reactions Medical Applications Radiation Detectors Previously Review Problem: A beam of particles passes undeflected through crossed electric and magnetic fields. When the electric field is switched off, the beam splits up in several beams. This splitting is due to the particles in the beam having different A. masses. B. velocities. C. charges. D. some combination of the above E. none of the above r=mv/qb Processes of Nuclear Energy Fission A nucleus of large mass number splits into two smaller nuclei Fusion Two light nuclei fuse to form a heavier nucleus Large amounts of energy are released in either case 1
2 Processes of Nuclear Energy Fission A nucleus of large mass number splits into two smaller nuclei Fusion Two light nuclei fuse to form a heavier nucleus Large amounts of energy are released in either case Nuclear Fission A heavy nucleus splits into two smaller nuclei The total mass of the products is less than the original mass of the heavy nucleus First observed in 1939 by Otto Hahn and Fritz Strassman following basic studies by Fermi Lisa Meitner and Otto Frisch soon explained what had happened Fission of 235 U by a slow (low energy) neutron n+ 92U 92U* X + Y + neutrons 236 U* is an intermediate, short-lived state X and Y are called fission fragments Many combinations of X and Y satisfy the requirements of conservation of energy and charge Sequence of Events in Fission Energy in a Fission Process The 235 U nucleus captures a thermal (slow-moving) neutron This capture results in the formation of 236 U*, and the excess energy of this nucleus causes it to undergo violent oscillations The 236 U* nucleus becomes highly elongated, and the force of repulsion between the protons tends to increase the distortion The nucleus splits into two fragments, emitting several neutrons in the process Binding energy for heavy nuclei is about 7.2 MeV per nucleon Binding energy for intermediate nuclei is about 8.2 MeV per nucleon Therefore, the fission fragments have less mass than the nucleons in the original nuclei This decrease in mass per nucleon appears as released energy in the fission event An estimate of the energy released Assume a total of 240 nucleons Releases about 1 MeV per nucleon 8.2 MeV 7.2 MeV Total energy released is about 240 MeV This is very large compared to the amount of energy released in chemical processes 2
3 QUICK QUIZ In the first atomic bomb, the energy released was equivalent to about 30 kilotons of TNT, where a ton of TNT releases an energy of J. The amount of mass converted into energy in this event is nearest to: (a) 1 μg, (b) 1 mg, (c) 1 g, (d) 1 kg, (e) 20 kilotons Chain Reaction Neutrons are emitted when 235 U undergoes fission These neutrons are then available to trigger fission in other nuclei This process is called a chain reaction If uncontrolled, a violent explosion can occur The principle behind the nuclear bomb, where 1 g of U can release energy equal to about tons of TNT (c). The total energy released was E = ( ton)( J/ton) = J. The mass equivalent of this quantity of energy is: m = c E J = 8 ( m/s) 1 3 = kg ~1g Nuclear Reactor A nuclear reactor is a system designed to maintain a self-sustained sustained chain reaction The reproduction constant,, K, is defined as the average number of neutrons from each fission event that will cause another fission event The maximum value of K from uranium fission is 2.5 Two 235 U reactions, one yields 3 the other 2 neutrons In practice, K is less than this A self-sustained sustained reaction has K = 1 Basic Reactor Design Fuel elements consist of enriched uranium (a few % 235 U rest 238 U) The moderator material helps to slow down the neutrons The control rods absorb neutrons When K = 1, the reactor is said to be critical The chain reaction is self- sustaining When K < 1, the reactor is said to be subcritical The reaction dies out When K > 1, the reactor is said to be supercritical A run-away chain reaction occurs Cadmium D 2 O, graphite 3
4 Schematic of a Fission Reactor Nuclear Fusion When two light nuclei combine to form a heavier nucleus Is exothermic for nuclei having a mass less than ~20 (Iron is the limit, Z=26, A=56) The sun is a large fusion reactor The sun balances gravity with fusion energy First steps: Sun s s Proton Cycle H + 1H 2He + γ Followed by H He or He He fusion: or H + H H + e + ν H + He He + e + ν e He + He He + H + H Total energy released is 25 MeV e 2% of sun s energyis carried by neutrinos Net Result 4 protons (hydrogen nuclei) combine to give An alpha particle (a helium nucleus) Two positrons One or two neutrinos (they easily escape) Some gamma ray photons (absorbed) The two positrons combine with electrons to form more gamma photons The photons are usually absorbed and so they heat the sun (blackbody spectrum) 4
5 Fusion Reactors Enormous energy in a small amount of fuel 0.06g of deuterium could be extracted from 1 gal of water This represents the equivalent energy of ~6x10 9 J Fusion reactor would most likely use deuterium and tritium H + H He + n, Q = 3.27 MeV H + 1H 1H + 1H, Q = 4.03 MeV H + H He + n, Q = MeV Advantages of fusion power Fuel costs are relatively small Few radioactive by-products of fusion reaction (mostly helium-3 3 and helium-4) Disadvantages of fusion power Hard to force two charged nuclei together Reactor is complex and expensive Need high temperatures and pressures to achieve fusion (~10 8 K) need a plasma Plasma confinement Plasma ion density, n Plasma confinement time, τ In order to achieve a fusion reaction need to satisfy Lawson s s criterion: nτ 10 s/cm nτ 10 s/cm So need 10 8 K for 1 second Deuterium- tritium reactor Deuterium- deuterium reactor Fusion Reactors - 1 Inertial confinement Inject fuel pellets and hit them with a laser (lots of lasers) or ion beams to heat them Imploding pellet compresses fuel to fusion densities Doesn t t require plasma confinement via magnetic fields Requires large facility to house lasers and target chamber. 5
6 National Ignition Facility the facility is very large, the size of a sports stadium the target is very small, the size of a BB- gun pellet the laser system is very powerful, equal to 1,000 times the electric generating power of the United States each laser pulse is very short, a few billionths of a second The beams are generated in the laser bay and deliverd to the target bay. The National Ignition Facility 6
7 The target chamber Fusion Reactors - 2 Magnetic field confinement Tokamak design a toroidal magnetic field First proposed by Russian scientists Fusion Reactors cont. ITER s proposed site layout Tokamak Fusion Test Reactor ITER 7
8 30.4 Elementary Particles First we studied atoms Next, atoms had electrons and a nucleus The nucleus is composed of neutrons and protons What s s next? Elementary particle interactions The scattering of two electrons via a coulomb force This virtual photon is said to mediate the electromagnetic force. The virtual photon can never be detected because it only lasts for a vanishing small time. An simple example of a Feynman diagram Interactions continued More examples of Feynman diagrams Can have similar diagrams with other particles and other forces Strong force, weak force, gravity Basic idea of exchange of a virtual particle is the common theme. 8
9 30.5 The Fundamental Forces in Nature Strong Force Short range ~ m (1 fermi) Responsible for binding of quarks into neutrons and protons Gluon Electromagnetic Force 10-2 as strong as strong force 1/r 2 force law Binding of atoms and molecules Photon Weak force ~ 10-6 times as strong as the strong force Responsible for beta decay, very short range ~10-18 m W +, W - and Z 0 bosons Gravitational Force times as strong as the strong force Also 1/r 2 force law Graviton 30.6 Positrons and Antiparticles Dirac proposed the positron to solve a negative energy problem (Dirac( sea) The general implication is that for every particle there is an antiparticle (symmetry) Other antiparticles: antiproton, antineutrino Usually denoted with a bar over symbol Some particles are their own antiparticles photon, neutral pion: γ, π Mesons Part of an early theory to describe nuclear interactions Mass between a electron and a proton Flavors Charged π meson: π +, π,mass MeV/c 2 Netral π meson,, π 0,mass MeV/c 2 Lifetimes 2.6x10-8 s for π +, π 8.3x s for π 0 More Mesons Also have heavier mesons Kaons ~500 MeV/c 2 Etas 548 and 958 MeV/c 2 (note, mass of η is greater than proton mass) 9
10 30.8 Particle Classification (Classify the animals in the particle zoo) Hadrons (strong force interaction, composed of quarks) Hadrons (strong force interaction, composed of quarks) We already met the mesons (middle( weights) Decay into electrons, neutrinos and photons Baryons,, i.e. the proton and neutron (the heavy particles) Still other more exotic baryons: Λ, Σ, Ξ, Ω all are heavier than the proton Decay into end products that include a proton Particle Classification cont. Leptons Small or light weight particles Are point like particles no internal structure (yet) 6 leptons (and their antiparticles 6 more) Electron e, e muon μ, tau τ and their associated neutrinos: ν e, ν μ, ν τ Neutrinos have tiny mass, ~3 ev/c 2 Some members of the Zoo Particle Physics Conservation Laws So far in Physics we have conservation of energy, momentum (linear and angular), charge, spin. Now we add more to help balance particle reactions Baryon number: B = +1 for baryons, -11 for anti-baryons Eg.. Proton, neutron have B = +1 p, n, antiparticles have B = -1 B = 0 for all other particles (non-baryons) 10
11 More Conservation Laws Lepton number L = +1 for leptons, -11 for anti-leptons L = 0 for non-leptons Example for electrons: Electron e, electron neutrino ν e have L e = +1 Anti electron and antineutrino have L e = -1 Other leptons have L e = 0 BUT have their own lepton numbers, L μ, L τ Refer to table 30.2 Example neutron decay Consider the decay of the neutron + - n p + e + ν e Before: B = +1, L e = 0 After: B = +1, L e = = 0 Quiz 30.2 Which of the following cannot occur? (a) (b) (c) (d) p + p p + p + p - n p + e + e - - μ e + ν e + νμ - - π μ +νμ ν Quiz answer The disallowed reaction is (a) because Charge is not conserved: Q = +2 Q = +1 Baryon number is also not conserved: B = +2 B = = +1 p + p p + p + p 11
12 Strangeness Several particles found to have unusual (strange) properties: Always produced in pairs π - + p + K 0 + Λ 0 but not π - + p + K 0 + n Decay is slow (indicative of weak interaction rather than strong) Half-lives lives of order of to 10-8 sec Members of the strange club: K, Λ, Σ More Strangeness Explanation lies in the addition of a new conservation law Strangeness, S One of the pair of strange particles gets S=+1 the other S=-1. All other particles get S=0. So in the previous reaction, strangeness is conserved: Before S=0; After S= = 0 Second reaction violates strangeness Example 30.6: Strangeness Conservation Consider: π - + n K + + Σ - Before: S=0+0=0 (no strange particles) After: K + has S=+1, Σ - has S = -11 thus the net strangeness S = = 0 So reaction does not violate law of conservation of strangeness, the reaction is allowed The Eightfold Way Consulting table 30.2, Take the first 8 baryons and plot Strangeness vs. Charge. We get an interesting picture. A hexagonal pattern emerges. If we do the same for the spin 0 mesons we also get a hexagonal pattern. 12
13 The Eightfold Way The Original Quark Model (in B/W) Gell-Mann (1961) proposed hadrons have structure, i.e. composed of a more fundamental type of particle. Quarks have fractional charge e/3 or 2e/3 Three types u, d, s: up, down, strange Mesons were made of 2 quarks: q, q Baryons were made of 3 quarks But that wasn enough! Properties of Quarks and Antiquarks Soon after, experimental discrepancies required the addition of three more quarks Top, bottom and charm: t, b, c And three more conservation laws: C, B, T for charm, bottomness and topness 13
14 Fundamental Particles: Properties Particle u d c s t b Quarks Rest Energy 360 MeV 360 MeV 1500 MeV 540 MeV 173 MeV 5 GeV Charge (e) +2/3-1/3 +2/3-1/3 +2/3-1/3 Fundamental Particles Properties continued Particle e - μ - τ - ν e ν μ ν τ Leptons Rest Energy 511 kev 107 MeV 1784 MeV < 30 ev < 0.5 MeV < 250 MeV Charge -e -e -e Quarks in Mesons and Baryons We should still be in B/W! Color Because of the Pauli exclusion principle (all quarks are spin ½ particles) can t t have three of the same particles occupying the same state. Example: Ω - is (sss( sss) ) so need three different yet strange quarks So colored quarks were proposed 14
15 Color continued Three color charges were added Red, green blue: r, g, b And three anti-colors antired, antigreen and antiblue: r, g, b Mesons have a color anticolor pair Spin is either zero or 1 so can have or Baryons must have three different colors Spin is ½ so have or Quarks combinations with color Total spin is 0 or 1 Total spin is ½ or 3/2 Quantum Chromodynamics In analogy with photons and the electromagnetic force, an interaction between colored quarks is the result of color force 8 colored gluons. The general theory is complex but explains experimental results better. Numerical results can be very hard to calculate Opposite colors attract, red-antired antired,, in analogy with electromagnetism. Different colors also attract though less strongly Residual color force is responsible for nuclear force that bind protrons and neutrons. Interactions in the Yukawa pion and quark-gluon models Yukawa s pion model Quark QCD model In both cases a proton-neutron pair scatter off each other and exchange places. 15
16 The Standard Model History of the Universe and of the four forces Energy: ev Time: sec Big Bang Model A broadly accepted theory for the origin and evolution of our universe. Time It postulates that 12 to 14 billion years ago, the portion of the universe we can see today was only a few millimeters across. It has since expanded from this hot dense state into the vast and much cooler cosmos we currently inhabit. In the beginning, there was a Big Bang, a colossal explosion from which everything in the Universe sprung out. 16
17 Experimental Evidence of the Big Bang Expansion of the universe Edwin Hubble's 1929 observation that galaxies were generally receding from us provided the first clue that the Big Bang theory might be right. Abundance of the light elements H, He, Li The Big Bang theory predicts that these light elements should have been fused from protons and neutrons in the first few minutes after the Big Bang. The cosmic microwave background (CMB) radiation The early universe should have been very hot. The cosmic microwave background radiation is the remnant heat leftover from the Big Bang. Cosmic Microwave Background 99.97% of the radiant energy of the Universe was released within the first year after the Big Bang itself and now permeate space in the form of a thermal 3 K radiation field. COBE CMB Measurement CMB spectrum is that of a nearly perfect blackbody with a temperature of / K. Observation matches predictions of the hot Big Bang theory extraordinarily well. Deviation from perfect black body spectrum less than 0.03 % Nearly all of the radiant energy of the Universe was released within the first year after the Big Bang. How did we get from there to here? 17
18 Let there be light: 400, ,000 years 18
General Physics (PHY 2140)
General Physics (PHY 2140) Lecture 20 Modern Physics Nuclear Energy and Elementary Particles Fission, Fusion and Reactors Elementary Particles Fundamental Forces Classification of Particles Conservation
More informationGeneral Physics (PHY 2140)
General Physics (PHY 2140) Lecture 20 Modern Physics Nuclear Energy and Elementary Particles Fission, Fusion and Reactors Elementary Particles Fundamental Forces Classification of Particles Conservation
More informationChapter 30. Nuclear Energy and Elementary Particles
Chapter 30 Nuclear Energy and Elementary Particles Processes of Nuclear Energy Fission A nucleus of large mass number splits into two smaller nuclei Fusion Two light nuclei fuse to form a heavier nucleus
More informationLecture 14, 8/9/2017. Nuclear Reactions and the Transmutation of Elements Nuclear Fission; Nuclear Reactors Nuclear Fusion
Lecture 14, 8/9/2017 Nuclear Reactions and the Transmutation of Elements Nuclear Fission; Nuclear Reactors Nuclear Fusion Nuclear Reactions and the Transmutation of Elements A nuclear reaction takes place
More informationChapter 46. Particle Physics and Cosmology
Chapter 46 Particle Physics and Cosmology Atoms as Elementary Particles Atoms From the Greek for indivisible Were once thought to be the elementary particles Atom constituents Proton, neutron, and electron
More informationPreview. Subatomic Physics Section 1. Section 1 The Nucleus. Section 2 Nuclear Decay. Section 3 Nuclear Reactions. Section 4 Particle Physics
Subatomic Physics Section 1 Preview Section 1 The Nucleus Section 2 Nuclear Decay Section 3 Nuclear Reactions Section 4 Particle Physics Subatomic Physics Section 1 TEKS The student is expected to: 5A
More informationParticle Physics Outline the concepts of particle production and annihilation and apply the conservation laws to these processes.
Particle Physics 12.3.1 Outline the concept of antiparticles and give examples 12.3.2 Outline the concepts of particle production and annihilation and apply the conservation laws to these processes. Every
More information32 IONIZING RADIATION, NUCLEAR ENERGY, AND ELEMENTARY PARTICLES
32 IONIZING RADIATION, NUCLEAR ENERGY, AND ELEMENTARY PARTICLES 32.1 Biological Effects of Ionizing Radiation γ-rays (high-energy photons) can penetrate almost anything, but do comparatively little damage.
More informationChapter 22. Preview. Objectives Properties of the Nucleus Nuclear Stability Binding Energy Sample Problem. Section 1 The Nucleus
Section 1 The Nucleus Preview Objectives Properties of the Nucleus Nuclear Stability Binding Energy Sample Problem Section 1 The Nucleus Objectives Identify the properties of the nucleus of an atom. Explain
More informationParticle Physics. All science is either physics or stamp collecting and this from a 1908 Nobel laureate in Chemistry
Particle Physics JJ Thompson discovered electrons in 1897 Rutherford discovered the atomic nucleus in 1911 and the proton in 1919 (idea of gold foil expt) All science is either physics or stamp collecting
More informationPhysics 4213/5213 Lecture 1
August 28, 2002 1 INTRODUCTION 1 Introduction Physics 4213/5213 Lecture 1 There are four known forces: gravity, electricity and magnetism (E&M), the weak force, and the strong force. Each is responsible
More informationChapter 32 Lecture Notes
Chapter 32 Lecture Notes Physics 2424 - Strauss Formulas: mc 2 hc/2πd 1. INTRODUCTION What are the most fundamental particles and what are the most fundamental forces that make up the universe? For a brick
More informationMatter: it s what you have learned that makes up the world Protons, Neutrons and Electrons
Name The Standard Model of Particle Physics Matter: it s what you have learned that makes up the world Protons, Neutrons and Electrons Just like there is good and evil, matter must have something like
More informationLecture PowerPoint. Chapter 32 Physics: Principles with Applications, 6 th edition Giancoli
Lecture PowerPoint Chapter 32 Physics: Principles with Applications, 6 th edition Giancoli 2005 Pearson Prentice Hall This work is protected by United States copyright laws and is provided solely for the
More informationOption 212: UNIT 2 Elementary Particles
Department of Physics and Astronomy Option 212: UNIT 2 Elementary Particles SCHEDULE 26-Jan-15 13.pm LRB Intro lecture 28-Jan-15 12.pm LRB Problem solving (2-Feb-15 1.am E Problem Workshop) 4-Feb-15 12.pm
More informationMost of Modern Physics today is concerned with the extremes of matter:
Most of Modern Physics today is concerned with the extremes of matter: Very low temperatures, very large numbers of particles, complex systems Æ Condensed Matter Physics Very high temperatures, very large
More informationElementary Particle Physics Glossary. Course organiser: Dr Marcella Bona February 9, 2016
Elementary Particle Physics Glossary Course organiser: Dr Marcella Bona February 9, 2016 1 Contents 1 Terms A-C 5 1.1 Accelerator.............................. 5 1.2 Annihilation..............................
More informationPHY-105: Introduction to Particle and Nuclear Physics
M. Kruse, Spring 2011, Phy-105 PHY-105: Introduction to Particle and Nuclear Physics Up to 1900 indivisable atoms Early 20th century electrons, protons, neutrons Around 1945, other particles discovered.
More informationMost of Modern Physics today is concerned with the extremes of matter:
Most of Modern Physics today is concerned with the extremes of matter: Very low temperatures, very large numbers of particles, complex systems Æ Condensed Matter Physics Very high temperatures, very large
More informationLecture PowerPoint. Chapter 31 Physics: Principles with Applications, 6 th edition Giancoli
Lecture PowerPoint Chapter 31 Physics: Principles with Applications, 6 th edition Giancoli 2005 Pearson Prentice Hall This work is protected by United States copyright laws and is provided solely for the
More informationFUNDAMENTAL PARTICLES CLASSIFICATION! BOSONS! QUARKS! FERMIONS! Gauge Bosons! Fermions! Strange and Charm! Top and Bottom! Up and Down!
FUNDAMENTAL PARTICLES CLASSIFICATION! BOSONS! --Bosons are generally associated with radiation and are sometimes! characterized as force carrier particles.! Quarks! Fermions! Leptons! (protons, neutrons)!
More informationNuclear Physics and Nuclear Reactions
Slide 1 / 33 Nuclear Physics and Nuclear Reactions The Nucleus Slide 2 / 33 Proton: The charge on a proton is +1.6x10-19 C. The mass of a proton is 1.6726x10-27 kg. Neutron: The neutron is neutral. The
More informationNUCLEAR AND PARTICLE PHYSICS (PH242) PARTICLE PHYSICS
NUCLEAR AND PARTICLE PHYSICS (PH242) PARTICLE PHYSICS History of Elementary Particles THE CLASSICAL ERA (1897-1932) Elementary particle physics was born in 1897 with J.J. Thomson s discovery of the ELECTRONS
More informationNuclear and Particle Physics 3: Particle Physics. Lecture 1: Introduction to Particle Physics February 5th 2007
Nuclear and Particle Physics 3: Particle Physics Lecture 1: Introduction to Particle Physics February 5th 2007 Particle Physics (PP) a.k.a. High-Energy Physics (HEP) 1 Dr Victoria Martin JCMB room 4405
More informationLecture PowerPoints. Chapter 31 Physics: Principles with Applications, 7th edition Giancoli
Lecture PowerPoints Chapter 31 Physics: Principles with Applications, 7th edition Giancoli This work is protected by United States copyright laws and is provided solely for the use of instructors in teaching
More informationGeneral and Inorganic Chemistry I.
General and Inorganic Chemistry I. Lecture 2 István Szalai Eötvös University István Szalai (Eötvös University) Lecture 2 1 / 44 Outline 1 Introduction 2 Standard Model 3 Nucleus 4 Electron István Szalai
More informationQuantum Numbers. Elementary Particles Properties. F. Di Lodovico c 1 EPP, SPA6306. Queen Mary University of London. Quantum Numbers. F.
Elementary Properties 1 1 School of Physics and Astrophysics Queen Mary University of London EPP, SPA6306 Outline Most stable sub-atomic particles are the proton, neutron (nucleons) and electron. Study
More informationLecture Outlines Chapter 32. Physics, 3 rd Edition James S. Walker
Lecture Outlines Chapter 32 Physics, 3 rd Edition James S. Walker 2007 Pearson Prentice Hall This work is protected by United States copyright laws and is provided solely for the use of instructors in
More informationOverview. The quest of Particle Physics research is to understand the fundamental particles of nature and their interactions.
Overview The quest of Particle Physics research is to understand the fundamental particles of nature and their interactions. Our understanding is about to take a giant leap.. the Large Hadron Collider
More informationPhys 102 Lecture 28 Life, the universe, and everything
Phys 102 Lecture 28 Life, the universe, and everything 1 Today we will... Learn about the building blocks of matter & fundamental forces Quarks and leptons Exchange particle ( gauge bosons ) Learn about
More informationOption 212: UNIT 2 Elementary Particles
Department of Physics and Astronomy Option 212: UNIT 2 Elementary Particles SCHEDULE 26-Jan-15 13.00pm LRB Intro lecture 28-Jan-15 12.00pm LRB Problem solving (2-Feb-15 10.00am E Problem Workshop) 4-Feb-15
More informationEarlier in time, all the matter must have been squeezed more tightly together and a lot hotter AT R=0 have the Big Bang
Re-cap from last lecture Discovery of the CMB- logic From Hubble s observations, we know the Universe is expanding This can be understood theoretically in terms of solutions of GR equations Earlier in
More informationReview Chap. 18: Particle Physics
Final Exam: Sat. Dec. 18, 2:45-4:45 pm, 1300 Sterling Exam is cumulative, covering all material Review Chap. 18: Particle Physics Particles and fields: a new picture Quarks and leptons: the particle zoo
More information1. What does this poster contain?
This poster presents the elementary constituents of matter (the particles) and their interactions, the latter having other particles as intermediaries. These elementary particles are point-like and have
More informationEssential Physics II. Lecture 14:
Essential Physics II E II Lecture 14: 18-01-16 Last lecture of EP2! Congratulations! This was a hard course. Be proud! Next week s exam Next Monday! All lecture slides on course website: http://astro3.sci.hokudai.ac.jp/~tasker/teaching/ep2
More informationNuclear Physics and Radioactivity
Nuclear Physics and Radioactivity Structure and Properties of the Nucleus Nucleus is made of protons and neutrons Proton has positive charge: Neutron is electrically neutral: Neutrons and protons are collectively
More informationParticles. Constituents of the atom
Particles Constituents of the atom For Z X = mass number (protons + neutrons), Z = number of protons Isotopes are atoms with the same number of protons number but different number of neutrons. charge Specific
More informationCHAPTER 7 TEST REVIEW
IB PHYSICS Name: Period: Date: # Marks: 94 Raw Score: IB Curve: DEVIL PHYSICS BADDEST CLASS ON CAMPUS CHAPTER 7 TEST REVIEW 1. An alpha particle is accelerated through a potential difference of 10 kv.
More informationModern Physics: Standard Model of Particle Physics (Invited Lecture)
261352 Modern Physics: Standard Model of Particle Physics (Invited Lecture) Pichet Vanichchapongjaroen The Institute for Fundamental Study, Naresuan University 1 Informations Lecturer Pichet Vanichchapongjaroen
More informationCosmology and particle physics
Cosmology and particle physics Lecture notes Timm Wrase Lecture 5 The thermal universe - part I In the last lecture we have shown that our very early universe was in a very hot and dense state. During
More information1. Introduction. Particle and Nuclear Physics. Dr. Tina Potter. Dr. Tina Potter 1. Introduction 1
1. Introduction Particle and Nuclear Physics Dr. Tina Potter Dr. Tina Potter 1. Introduction 1 In this section... Course content Practical information Matter Forces Dr. Tina Potter 1. Introduction 2 Course
More informationβ and γ decays, Radiation Therapies and Diagnostic, Fusion and Fission Final Exam Surveys New material Example of β-decay Beta decay Y + e # Y'+e +
β and γ decays, Radiation Therapies and Diagnostic, Fusion and Fission Last Lecture: Radioactivity, Nuclear decay Radiation damage This lecture: nuclear physics in medicine and fusion and fission Final
More informationChapter 25: Radioactivity, Nuclear Processes, and Applications. What do we know about the nucleus? James Chadwick and the discovery of the neutron
Chapter 25: Radioactivity, Nuclear Processes, and Applications What do we know about the nucleus? Rutherford discovered Contains positively charged protons. Held together by the Nuclear Strong Force. The
More informationINTRODUCTION TO THE STANDARD MODEL OF PARTICLE PHYSICS
INTRODUCTION TO THE STANDARD MODEL OF PARTICLE PHYSICS Class Mechanics My office (for now): Dantziger B Room 121 My Phone: x85200 Office hours: Call ahead, or better yet, email... Even better than office
More informationcgrahamphysics.com Particles that mediate force Book pg Exchange particles
Particles that mediate force Book pg 299-300 Exchange particles Review Baryon number B Total # of baryons must remain constant All baryons have the same number B = 1 (p, n, Λ, Σ, Ξ) All non baryons (leptons
More informationAtoms and Nuclei 1. The radioactivity of a sample is X at a time t 1 and Y at a time t 2. If the mean life time of the specimen isτ, the number of atoms that have disintegrated in the time interval (t
More informationNUCLEI. Atomic mass unit
13 NUCLEI Atomic mass unit It is a unit used to express the mass of atoms and particles inside it. One atomic mass unit is the mass of atom. 1u = 1.660539 10. Chadwick discovered neutron. The sum of number
More information9.2.E - Particle Physics. Year 12 Physics 9.8 Quanta to Quarks
+ 9.2.E - Particle Physics Year 12 Physics 9.8 Quanta to Quarks + Atomic Size n While an atom is tiny, the nucleus is ten thousand times smaller than the atom and the quarks and electrons are at least
More information1 Introduction. 1.1 The Standard Model of particle physics The fundamental particles
1 Introduction The purpose of this chapter is to provide a brief introduction to the Standard Model of particle physics. In particular, it gives an overview of the fundamental particles and the relationship
More informationAn introduction to Nuclear Physics
An introduction to Nuclear Physics Jorge Pereira pereira@nscl.msu.edu National Superconducting Cyclotron Laboratory Joint Institute for Nuclear Astrophysics The Origin of Everything Layout The Nucleus.
More informationTHE STANDARD MODEL OF MATTER
VISUAL PHYSICS ONLINE THE STANDARD MODEL OF MATTER The "Standard Model" of subatomic and sub nuclear physics is an intricate, complex and often subtle thing and a complete study of it is beyond the scope
More informationJohn Ellison University of California, Riverside. Quarknet 2008 at UCR
Overview of Particle Physics John Ellison University of California, Riverside Quarknet 2008 at UCR 1 Particle Physics What is it? Study of the elementary constituents of matter And the fundamental forces
More informationT7-1 [255 marks] The graph shows the relationship between binding energy per nucleon and nucleon number. In which region are nuclei most stable?
T7-1 [255 marks] 1. In the Geiger Marsden experiment alpha particles were directed at a thin gold foil. Which of the following shows how the majority of the alpha particles behaved after reaching the foil?
More informationChapter 46 Solutions
Chapter 46 Solutions 46.1 Assuming that the proton and antiproton are left nearly at rest after they are produced, the energy of the photon E, must be E = E 0 = (938.3 MeV) = 1876.6 MeV = 3.00 10 10 J
More informationElectron-positron pairs can be produced from a photon of energy > twice the rest energy of the electron.
Particle Physics Positron - discovered in 1932, same mass as electron, same charge but opposite sign, same spin but magnetic moment is parallel to angular momentum. Electron-positron pairs can be produced
More informationLecture 31 Chapter 22, Sections 3-5 Nuclear Reactions. Nuclear Decay Kinetics Fission Reactions Fusion Reactions
Lecture Chapter, Sections -5 Nuclear Reactions Nuclear Decay Kinetics Fission Reactions Fusion Reactions Gamma Radiation Electromagnetic photons of very high energy Very penetrating can pass through the
More informationFundamental Forces. Range Carrier Observed? Strength. Gravity Infinite Graviton No. Weak 10-6 Nuclear W+ W- Z Yes (1983)
Fundamental Forces Force Relative Strength Range Carrier Observed? Gravity 10-39 Infinite Graviton No Weak 10-6 Nuclear W+ W- Z Yes (1983) Electromagnetic 10-2 Infinite Photon Yes (1923) Strong 1 Nuclear
More informationParticles and Forces
Particles and Forces Particles Spin Before I get into the different types of particle there's a bit more back story you need. All particles can spin, like the earth on its axis, however it would be possible
More informationLecture 2: The First Second origin of neutrons and protons
Lecture 2: The First Second origin of neutrons and protons Hot Big Bang Expanding and cooling Soup of free particles + anti-particles Symmetry breaking Soup of free quarks Quarks confined into neutrons
More informationA is called the mass number gives, roughly, the mass of the nucleus or atom in atomic mass units = amu = u
5/5 A is called the mass number gives, roughly, the mass of the nucleus or atom in atomic mass units = amu = u The number of neutrons in the nucleus is given by the symbol N. Clearly, N = A Z. Isotope:
More informationLecture 02. The Standard Model of Particle Physics. Part I The Particles
Lecture 02 The Standard Model of Particle Physics Part I The Particles The Standard Model Describes 3 of the 4 known fundamental forces Separates particles into categories Bosons (force carriers) Photon,
More informationNuclear Physics. Slide 1 / 87. Slide 2 / 87. Slide 3 / 87. Table of Contents.
Slide 1 / 87 Slide 2 / 87 Nuclear Physics www.njctl.org Table of Contents Slide 3 / 87 Click on the topic to go to that section Nuclear Structure Binding Energy and Mass Defect Radioactivity Nuclear Half-life
More informationNuclear Physics
Slide 1 / 87 Slide 2 / 87 Nuclear Physics www.njctl.org Slide 3 / 87 Table of Contents Click on the topic to go to that section Nuclear Structure Binding Energy and Mass Defect Radioactivity Nuclear Half-life
More informationDEVIL PHYSICS THE BADDEST CLASS ON CAMPUS IB PHYSICS
DEVIL PHYSICS THE BADDEST CLASS ON CAMPUS IB PHYSICS LSN 7-3: THE STRUCTURE OF MATTER Questions From Reading Activity? Essential Idea: It is believed that all the matter around us is made up of fundamental
More informationParticle physics: what is the world made of?
Particle physics: what is the world made of? From our experience from chemistry has told us about: Name Mass (kg) Mass (atomic mass units) Decreasing mass Neutron Proton Electron Previous lecture on stellar
More informationInteractions. Laws. Evolution
Lecture Origin of the Elements MODEL: Origin of the Elements or Nucleosynthesis Fundamental Particles quarks, gluons, leptons, photons, neutrinos + Basic Forces gravity, electromagnetic, nuclear Interactions
More informationThe first 400,000 years
The first 400,000 years All about the Big Bang Temperature Chronology of the Big Bang The Cosmic Microwave Background (CMB) The VERY early universe Our Evolving Universe 1 Temperature and the Big Bang
More informationElementary particles, forces and Feynman diagrams
Elementary particles, forces and Feynman diagrams Particles & Forces quarks Charged leptons (e,µ,τ) Neutral leptons (ν) Strong Y N N Electro Magnetic Y Y N Weak Y Y Y Quarks carry strong, weak & EM charge!!!!!
More informationChapter 10 - Nuclear Physics
The release of atomic energy has not created a new problem. It has merely made more urgent the necessity of solving an existing one. -Albert Einstein David J. Starling Penn State Hazleton PHYS 214 Ernest
More informationNuclear Physics. Slide 1 / 87. Slide 2 / 87. Slide 3 / 87. Table of Contents.
Slide 1 / 87 Slide 2 / 87 Nuclear Physics www.njctl.org Table of Contents Slide 3 / 87 Click on the topic to go to that section Nuclear Structure Binding Energy and Mass Defect Radioactivity Nuclear Half-life
More informationNuclear Physics. Nuclear Structure. Slide 1 / 87 Slide 2 / 87. Slide 4 / 87. Slide 3 / 87. Slide 6 / 87. Slide 5 / 87. Table of Contents.
Slide 1 / 87 Slide 2 / 87 Nuclear Physics www.njctl.org Slide 3 / 87 Slide 4 / 87 Table of Contents Click on the topic to go to that section Nuclear Structure Binding Energy and Mass Defect Radioactivity
More informationNuclear Energy Learning Outcomes
1 Nuclear Energy Learning Outcomes Describe the principles underlying fission and fusion. Interpret nuclear reactions. Discuss nuclear weapons. Describe the structure and operation of a nuclear reactor.
More informationNuclear Energy Learning Outcomes. Nuclear Fission. Chain Reaction
by fastfission public domain by fastfission public domain 1 Nuclear Energy Learning Outcomes Describe the principles underlying fission and fusion. Interpret nuclear reactions. Discuss nuclear weapons.
More informationNuclear Physics
Slide 1 / 87 Slide 2 / 87 Nuclear Physics www.njctl.org Slide 3 / 87 Table of Contents Click on the topic to go to that section Nuclear Structure Binding Energy and Mass Defect Radioactivity Nuclear Half-life
More informationChapter 22 Lecture. The Cosmic Perspective. Seventh Edition. The Birth of the Universe Pearson Education, Inc.
Chapter 22 Lecture The Cosmic Perspective Seventh Edition The Birth of the Universe The Birth of the Universe 22.1 The Big Bang Theory Our goals for learning: What were conditions like in the early universe?
More informationUnpressurized steam reactor. Controlled Fission Reactors. The Moderator. Global energy production 2000
From last time Fission of heavy elements produces energy Only works with 235 U, 239 Pu Fission initiated by neutron absorption. Fission products are two lighter nuclei, plus individual neutrons. These
More informationNuclear Reactions A Z. Radioactivity, Spontaneous Decay: Nuclear Reaction, Induced Process: x + X Y + y + Q Q > 0. Exothermic Endothermic
Radioactivity, Spontaneous Decay: Nuclear Reactions A Z 4 P D+ He + Q A 4 Z 2 Q > 0 Nuclear Reaction, Induced Process: x + X Y + y + Q Q = ( m + m m m ) c 2 x X Y y Q > 0 Q < 0 Exothermic Endothermic 2
More informationParticle Physics (concise summary) QuarkNet summer workshop June 24-28, 2013
Particle Physics (concise summary) QuarkNet summer workshop June 24-28, 2013 1 Matter Particles Quarks: Leptons: Anti-matter Particles Anti-quarks: Anti-leptons: Hadrons Stable bound states of quarks Baryons:
More informationPhysics 3204 UNIT 3 Test Matter Energy Interface
Physics 3204 UNIT 3 Test Matter Energy Interface 2005 2006 Time: 60 minutes Total Value: 33 Marks Formulae and Constants v = f λ E = hf h f = E k + W 0 E = m c 2 p = h λ 1 A= A T 0 2 t 1 2 E k = ½ mv 2
More informationParticles in the Early Universe
Particles in the Early Universe David Morrissey Saturday Morning Physics, October 16, 2010 Using Little Stuff to Explain Big Stuff David Morrissey Saturday Morning Physics, October 16, 2010 Can we explain
More informationVisit for more fantastic resources. AQA. A Level. A Level Physics. Particles (Answers) Name: Total Marks: /30
Visit http://www.mathsmadeeasy.co.uk/ for more fantastic resources. AQA A Level A Level Physics Particles (Answers) Name: Total Marks: /30 Maths Made Easy Complete Tuition Ltd 2017 1. This question explores
More informationNuclear Reactions and E = mc 2. L 38 Modern Physics [4] Hazards of radiation. Radiation sickness. Biological effects of nuclear radiation
L 38 Modern Physics [4] Nuclear physics what s s inside the nucleus and what holds it together what is radioactivity, halflife carbon dating Nuclear energy nuclear fission nuclear fusion nuclear reactors
More informationPhysics 7730: Particle Physics
Physics 7730: Particle Physics! Instructor: Kevin Stenson (particle physics experimentalist)! Office: Duane F317 (Gamow tower)! Email: kevin.stenson@colorado.edu! Phone: 303-492-1106! Web page: http://www-hep.colorado.edu/~stenson/!
More informationQuantum Mechanics. Exam 3. Photon(or electron) interference? Photoelectric effect summary. Using Quantum Mechanics. Wavelengths of massive objects
Exam 3 Hour Exam 3: Wednesday, November 29th In-class, Quantum Physics and Nuclear Physics Twenty multiple-choice questions Will cover:chapters 13, 14, 15 and 16 Lecture material You should bring 1 page
More informationNuclear Physics Part 3: Nuclear Energy
Nuclear Physics Part 3: Nuclear Energy Last modified: 24/10/2017 CONTENTS Fission & Fusion Definitions Binding Energy Curve Revisited Fission Spontaneous Fission Neutron-Induced Fission Controlled Fission
More informationThursday, April 23, 15. Nuclear Physics
Nuclear Physics Some Properties of Nuclei! All nuclei are composed of protons and neutrons! Exception is ordinary hydrogen with just a proton! The atomic number, Z, equals the number of protons in the
More informationGeneral Physics (PHY 2140)
General Physics (PHY 140) Lecture 18 Modern Physics Nuclear Physics Nuclear properties Binding energy Radioactivity The Decay Process Natural Radioactivity Last lecture: 1. Quantum physics Electron Clouds
More informationAstro-2: History of the Universe. Lecture 12; May
Astro-2: History of the Universe Lecture 12; May 23 2013 Previously on astro-2 The four fundamental interactions are? Strong, weak, electromagnetic and gravity. We think they are unified at high energies,
More informationThe Physics of Particles and Forces David Wilson
The Physics of Particles and Forces David Wilson Particle Physics Masterclass 21st March 2018 Overview David Wilson (TCD) Particles & Forces 2/30 Overview of Hadron Spectrum Collaboration (HadSpec) scattering
More informationPlasma Universe. The origin of CMB
Plasma Universe As we go back in time, temperature goes up. T=2.73(1+z) K At z~1100, T~3000 K About the same temperature as M-dwarfs Ionization of hydrogen atoms H + photon! p + e - Inverse process: recombination
More informationChem 481 Lecture Material 1/30/09
Chem 481 Lecture Material 1/30/09 Nature of Radioactive Decay The Standard Model in physics postulates that all particles in nature are composed of quarks and leptons and that they interact by exchange
More informationAlta Chemistry CHAPTER 25. Nuclear Chemistry: Radiation, Radioactivity & its Applications
CHAPTER 25 Nuclear Chemistry: Radiation, Radioactivity & its Applications Nuclear Chemistry Nuclear Chemistry deals with changes in the nucleus The nucleus of an atom contains Protons Positively Charged
More informationToday in Astronomy 142
Today in Astronomy 142! Elementary particles and their interactions, nuclei, and energy generation in stars.! Nuclear fusion reactions in stars TT Cygni: Carbon Star Credit: H. Olofsson (Stockholm Obs.)
More informationNuclear Fission. Conceptual Physics 11 th Edition. Nuclear Fission. Nuclear Fission. Nuclear Fission. This lecture will help you understand:
Conceptual Physics 11 th Edition A typical uranium fission reaction: Chapter 34: NUCLEAR FISSION AND FUSION Note the mass number as well as atomic numbers balance. This lecture will help you understand:
More informationFundamental Particles and Forces
Fundamental Particles and Forces A Look at the Standard Model and Interesting Theories André Gras PHYS 3305 SMU 1 Overview Introduction to Fundamental Particles and Forces Brief History of Discovery The
More informationRadioactivity. L 38 Modern Physics [4] Hazards of radiation. Nuclear Reactions and E = mc 2 Einstein: a little mass goes a long way
L 38 Modern Physics [4] Nuclear physics what s inside the nucleus and what holds it together what is radioactivity, halflife carbon dating Nuclear energy nuclear fission nuclear fusion nuclear reactors
More informationChapter 27 The Early Universe Pearson Education, Inc.
Chapter 27 The Early Universe Units of Chapter 27 27.1 Back to the Big Bang 27.2 The Evolution of the Universe More on Fundamental Forces 27.3 The Formation of Nuclei and Atoms 27.4 The Inflationary Universe
More informationFXA Candidates should be able to :
1 Candidates should be able to : MATTER AND ANTIMATTER Explain that since protons and neutrons contain charged constituents called quarks, they are therefore, not fundamental particles. Every particle
More informationActivity 12: Energy from Nuclear Reactions
Name Section Activity 12: Energy from Nuclear Reactions 12.1 A Model of the Composition of Nucleons 1) Formation of Nucleons Nucleons consist of quark trios. a) Place orange or green quarks into the metal
More informationBosons in the Zoo of Elementary Particles
Bosons in the Zoo of Elementary Particles Daniele Sasso * Abstract In this paper we want to raise the question concerning the physical identity of bosons and the function that they perform in the Non-Standard
More information