DOCSLIB.ORG

Accelerators Overview

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Accelerators Overview Introduction to Accelerators Overview Saturday Morning Physics Fermilab – October 18th Particle accelerators Particle accelerator is a device that uses electrostatic force to accelerate and electromagnetic fields to bend charge particles to high speeds and energy SMP - Introduction to Accelerators | fgg 2 What is a particle accelerator? Does anyone knows what . World’s biggest particle accelerator the name of this machine is? . 7 TeV energy , 17 miles (27 km) in circumference . 574 ft (~180 m) buried underground between the border of France and Switzerland heat matter at temperatures last seen since Big Bang LHC: Ulra High vacuum Order the magnitude lower than ISS space station Very low temperatures -456o F SMP - Introduction to Accelerators | fgg 3 How many accelerators are there? There are > 15,000 particle accelerators around the world Only research particle accelerators are shown here. Data: ELSA [http://www-elsa.physik.uni-bonn.de/accelerator_list.html] SMP - Introduction to Accelerators | fgg 4 How do they work? Which of these particles you cannot put into an accelerator? Required elements to make an accelerator Particles Energy Control Collision Detector e n p g l e r o e u o l c t t d t r o r o n a o n t n o m SMP - Introduction to Accelerators | fgg 5 Particle accelerators Modern Physics Computing Quantum Physics Accelerator design code Particle Physics High performance computing Engineering Radio Frequency Classical Physics Alignment & Survey Ultra high vacuum Mechanics Particle Electronics Electrodynamics Accelerator Magnet Technology Mechanical Cryogenics SMP - Introduction to Accelerators | fgg 6 A little bit about me… This is Originally from Sao Paulo (USP), Brazil great… What do I like… BRR!!! soccer, football, F1, ski, hiking, camping, Fermilab… relax on the beach…21F Here I come! Interval training workout Movies, concerts, plays, operas ~8,400Education miles – University later of Sao Paulo 1995 Ms in Theoretical Particle Physics 2000 PhD in Exp. Particle Physics 84F Feb ‘96 moved to US to develop my PhD work SMP - Introduction to Accelerators | fgg 7 Outline 1. INTRODUCTION 1. HISTORY OF ACCELERATORS 2. BEAM CONTROL 1. STEERING 2. FOCUSING 2. FNAL ACCELERATORS CHAIN 1. ACCELERATOR BASED EXPERIMENTS 2. BEAM DIAGNOSTICS 3. RADIATION 4. HOW ACCELERATORS ARE OPERATED 3. ACCELERATOR APPLICATIONS, TECHNOLOGY & FUTURE ACCELERATOS SMP - Introduction to Accelerators | fgg 8 Particle accelerators Modern Physics Computing Quantum Physics Accelerator design code Particle Physics High performance computing Engineering Radio Frequency Classical Physics Alignment & Survey Ultra high vacuum Mechanics Particle Electronics Electrodynamics Accelerator Magnet Technology Mechanical Cryogenics SMP - Introduction to Accelerators | fgg 9 Units .Energy is measured in units of electron volt (eV) . 1 eV : kinetic energy gained (or lost) by a unit charged particle after crossing an electrical potential of one volt . However, 1V = 1 J/C , so 1eV = (1.602x10-19 C)*1 J/C DE = qV elementary particle How fast is the particle moving? 1 2 E = mv , so v = 2퐸/푚 + V=1.5V - 2 INTRODUCTION = 2푥1.5푥(1.6푥10−19퐽)/(1.67푥10−27푘푔) ≌ 1.7푥104 푚/푠 remember that velocity of light is 3x108 m/s this is only 0.006 of speed of light!!! SMP - Introduction to Accelerators | fgg 10 Electrostatic The force from the electrical field will pull How many batteries would take to the particle and make it create a LHC accelerator? move increasing its speed INTRODUCTION until it moves really fast. So…does it mean that particles will be moving at 7푥1012 NO! relativistic effects Not very practical, is it? ≃ 4,000c??? 1.5 has to be considered (more later…) SMP - Introduction to Accelerators | fgg 11 Electromagnetism When a charge particle is placed in a magnetic field, it experiences a magnetic force when the charge is moving relative to the magnetic field 퐹 퐵 (perpendicular) 푣 INTRODUCTION 퐵 Magnetic field make particles to move on a circular path SMP - Introduction to Accelerators | fgg 12 Electrostatic & Electromagnetism While electric fields change the energy of the particles, Magnetics fields make them making the particles move follow a circular path Lorentz INTRODUCTION faster …. Equation of motion under Lorentz force 푑푝 퐹 = 푑푡 = q(퐸 + 푣 x퐵) SMP - Introduction to Accelerators | fgg 13 Relativity: momentum & energy Rest energy = 푚 푐 2 2 E0 0 Einstein’s relativity formula E = 푚푐 E Lorentz factor g = E mass of a moving 0 When particles are accelerated close to speed particle 푚 = g푚0 v of light, relativistic effects start counting... Normal veloci b = ty c Total Energy 2 2 2 2 2 2 2 E pc E = Ekin + m0c = 푚0푐 + 푝푐 INTRODUCTION E E0 pc E0 momentum and energy are not equal Non-relativistic p = m v p = 푚푣 = 푚0푐bg 0 E momentum and energy become closer pc High relativistic p = m0cg = E/c E0 SMP - Introduction to Accelerators | fgg 14 Length scale …why accelerators? In order to study small objects, the higher the energy of the probe one needs to use it ℎ De Broglie’s wavelength l = Planck constant h = 6.63x10−34J.s 푝 = 4.14x 10−15eV.s INTRODUCTION Picture from http://www.clab.edc.uoc.gr/materials/pc/surf/ accelerators_intro.html SMP - Introduction to Accelerators | fgg 15 Velocity as function of energy E= 훾푚푐2 relativistic More energy can be poured into the 2∗퐸 v= particles, giving a shorter l so that it 푚 Non-relativistic probes deeper into the sub-atomic world INTRODUCTION [MeV] SMP - Introduction to Accelerators | fgg 16 Early days… . 1870 Discovery of Cathode Rays Tube (CRT) by William Crookes . Propagation of electrons from the cathode to the anode William Crookes Electrons are emitted from a heated element (cathode) which resides inside INTRODUCTION glass tube under vacuum. Electrons are attracted to the anode and strike a flat screen coated with phosphor which glows Where was it used for? when struck by the beam of electrons Typical energies of about tens of thousands of eV SMP - Introduction to Accelerators | fgg 17 Early days… . 1895 Discover of X-Rays . X-rays are produced as the result Nobel Prize of changes in the positions of the 1901 electrons orbiting the nucleus An X-ray tube: electrons are accelerated by electrical field Wilhelm Rontgen and generate X-rays when they First X ray made in public. Medical hit a target. Society Jan 1896 INTRODUCTION . 1897 – Cavendish Laboratory . Demonstrates that cathode rays are made of particles . measured the mass to charge ratio, . 1,800 x lighter than hydrogen atom . Discovery of the first elementary particle electron SMP - Introduction to Accelerators | fgg 18 Timeline 1890 Rutherford develops the theory of atomic scattering using alpha-particles Rutherford need a more powerful source to 1900 continue his research Direct-Voltage accelerators 1927: “It has been my ambition to have Cockcroft & Walton & Van de Graaf available for study a copious supply of atoms electrostatic generator and electrons which have an individual 1930 1928 Gurney and Gamov predicted tunneling energy far transcending that of alpha and & Cockcroft-Walton start designing 800kW beta particles from radioactive bodies. I am hopeful that I may yet have my wish fulfilled.” 1940 SMP - Introduction to Accelerators | fgg 19 Cockcroft-Walton accelerator 1928-1930 Rutherford’s Laboratory . Nobel Prize . Voltage multiplier by using a stack of1951 capacitors and switch diodes Design for 800 kV, but reached 700kV John Cockcroft E.T..S. Walton Lithium atoms split with only 400 kV protons! First device to produce an artificial nuclear disintegration Main limitation INTRODUCTION Hard to reach ~1MV due to discharges through air and along material surfaces. Concept design First accelerator John Cockcroft , Ernest Rutherford, E.T..S. Walton SMP - Introduction to Accelerators | fgg 20 Examples of C-W accelerators BNL (USA) 1971-1988 INTRODUCTION CERN (CH-F) 1959-1993 FNAL (USA) 1969-2012 SMP - Introduction to Accelerators | fgg 21 The Van de Graaf generator . 1929-1933 VDG . Belt of insulating material carries electricity from a point source to a large insulated spherical conductor. Another belt delivers electricity of the opposite charge to another sphere Concept design R. J. Van de Graaff Main limitation . Tandem Graaf Accelerator (1950) Van de Graaf cannot go . Negative ions are accelerate towards a much beyond 10-20 MV. positive terminal located INTRODUCTION Electric breakdown in the center of a pressure tank was a . The negative ions pass through a foil the electrons fundamental are stripped, producing a limitation. positive-ion beam . The beam is then accelerated a second time away from the positive terminal SMP - Introduction to Accelerators | fgg 22 Examples of VDG & Tandem generators Daresbury (UK) 20MeV 1981 MIT (USA) 5MV generator 1933 INTRODUCTION 14UD 15MV ANU (Australia) Operational since 1973 Michigan (USA) 6MV Tandem Yale (USA) 1964-2011 22.4 MV Tandem BNL (USA) 15MV Fermilab (USA) SMP - Introduction to Accelerators | fgg 4.4 MV Pelletron23 Timeline 1890 Rutherford develops the theory 1927: “It has been my ambition to have of atomic scattering available for study a copious supply of atoms Rutherford need a more powerful source to and electrons which have an individual continue his research. 1900 energy far transcending that of alpha and beta particles from radioactive bodies. I am hopeful that I may yet have my with fulfilled.” Direct-Voltage accelerators Time-varying fields resonant acceleration Cockcroft & Walton & Van de Graaf electrostatic generator 1930 1924 Ising proposes time-varying fields 1928 Gurney and Gamov predicted tunneling across drift-tubes & Cockcroft-Walton start designing 800 kW 1928 Wideroe demonstrates Ising’s principle 1929 Lawrence creates cyclotron 1940 SMP - Introduction to Accelerators | fgg 24 Application of time-varying fields . 1924 Gustav Ising, (Sweden) . proposes applying much smaller voltage in an linear accelerator by using time-varying fields G. Ising Particles would be accelerated by using alternating electric fields, with “drift tubes” INTRODUCTION positioned at appropriate Ising’s idea intervals to shield the particles during the half-cycle when the Ising was unable to field is in the wrong direction demonstrate the concept for acceleration SMP - Introduction to Accelerators | fgg 25 .
Load more

Recommended publications
  • 00307399.Pdf
    + ASI&’rrrativc ActioIs/Eq51dS&MtSUdtyErrqsbyer < This work was supported by the National Cancer Institute, Division of Research Resources and Centers, Department of Health, Education, and Welfare. Edited by Ixruise Taylor, AT Division. DISCLAMER This report was prepared as an account of work sponsored by assagency of the Uruted States &rvcrrrment. Neither the United States Ciovernanerstnor any agency thereof, nor asryof their employru, makes any *anty, express or irnpfied, or assumesany legal liability or responsibility for the accuracy, completeness, or usefulnessof arsyirsfornsation, apparatus, product, or processdisclosed, or represents that its use would not infringe privately owned rights. References herein to any specitlc comnserciat product. process, or aer+ce by trade name, trademark, rnamafacmrer, or otherwise, does not necessady constitute or imply ita errdorsement, recommendation, or favoring by the Urdted States Government or any agency thersof. llte view and opinions of authors expressed herein do not nemsas-ity stare or reflect those of the United States Government or any agency thereof. LA-9144-MS UC-28 and UC-48 Issued: February 1982 . ● / A Linear Accelerator for Radioisotope Production L.D. Hansborough R. W. Harem J. E. Stovall i !-=-—- ‘ - I I . -.... J“’”’ .“ Los Alamos National Laboratory ~~~~la~~s Lo.Alamo.,New.exi..875.~ A LINEAR ACCELERATOR FOR RADIOISOTOPE PRODUCTION by L. D. Hansborough, R. W. Harem, and J. E. Stovall ABSTRACT A 200- to 500-uA source of 70- to 90-MeV protons would be a valuable asset to the nuclear medicine program. A linear accelerator (linac) can achieve this performance, and it can be extended to even higher energies and currents. Variable energy and current options are available.
    [Show full text]
  • Introduction to Accelerators
    Introduction to Accelerators Lecture 4 Basic Properties of Particle Beams William A. Barletta Director, United States Particle Accelerator School Dept. of Physics, MIT US Particle Accelerator School Homework item US Particle Accelerator School From the last lecture US Particle Accelerator School We computed the B-field from current loop with I = constant By the Biot-Savart law we found that on the z-axis I 2 2IR2 B = Rsin d zˆ = zˆ cr2 2 2 3/2 0 cR()+ z What happens if we drive the current to have a time variation? r R US Particle Accelerator School The far field B-field has a static dipole form Importantly the ring of current does not radiate US Particle Accelerator School Question to ponder: What is the field from this situation? r R We’ll return to this question in the second half of the course US Particle Accelerator School Is this really paradoxical? Let’s look at Maxwell’s equations Take the curl of xE Hence US Particle Accelerator School The dipole radiation field: note the similarity to the static dipole US Particle Accelerator School Now on to beams US Particle Accelerator School Beams: particle bunches with directed velocity Ions - either missing electrons (+) or with extra electrons (-) Electrons or positrons Plasma - ions plus electrons Source techniques depend on type of beam & on application US Particle Accelerator School Electron sources - thermionic Heated metals Some electrons have energies above potential barrier Cannot escape + HV Enough energy to escape # of electrons Work function = Electrons in a metal
    [Show full text]
  • Tutorial on Accelerator-Based Light Sources∗
    TUOAS1 Proceedings of 2011 Particle Accelerator Conference, New York, NY, USA A TUTORIAL ON ACCELERATOR-BASED LIGHT SOURCES∗ M. Borland† , ANL, Argonne, IL 60439, USA Abstract light compared to protons, electrons are far easier to ac- celerate to relativistic energies, and hence are preferred Accelerator-based light sources are some of the largest for radiation generation. The first accelerator-generated and most successful scientific user facilities in existence, x-rays were created by the rapid deflection and decel- serving tens of thousands of users each year. These im- eration electrons experience when hitting a metal target portant facilities enable research in diverse fields, includ- (bremsstrahlung radiation). A more controlled technique ing biology, pharmaceuticals, energy conservation and pro- uses a magnetic field to deflect the particle trajectory in a duction, data storage, and archaeology. In this tutorial, circular arc, which produces acceleration at right angles to we briefly review the history of accelerator-based light the direction of motion. sources. We present an overview of the different types of accelerator-based light sources, including a description of For circulating electrons with β 1, radiation is emit- their various operating principles, as well as a discussion of ted in a broad angular pattern at the revolution frequency. measures of performance. Technical challenges of current Radiation is emitted most strongly in the forward and back- and future light sources are also reviewed. ward directions, for which a distant observer sees the great- est acceleration. However, when β ≈ 1 the emitting elec- tron follows closely behind the forward-directed radiation, INTRODUCTION which has β =1.
    [Show full text]
  • A Vacuum Electrostatic Generator
    1465 A VACUUM ELECTROSTATIC GENERATOR B.H. Choi, H.D. Kang, W. Kim, B.H. Oh, Korea Advanced Energy Research Institute Daeduk-Danji, Choongnam, 301-353, Korea and K.H. Chung Seoul National University Shinrim-Dong, Kwanak-Ku, Seoul, 151-741, Korea Abstract insulator supports the breakdown strength is limited to about 30 kV/cm due to the flashover phenomena on A compact electrostatic generator designed with the insulator surface. the principle of vacuum insulation has been developed. The concept of vacuum insulation instead of gas It consists of a rotating insulation disk with charge- insulation for the electrostatic generator design has carrying conductors placed around the circumference some advantages, such as the capability to hold the n n ti a non-contact induction system with R” electron high voltage in narrow inductor gap, elimination cf gun. The usable voltage of 130 kV with the generating the electrical cant acr problem by utilizing the current of about 300 pA has been obtained at the oper- non-contact induction method, posstbility of fice ational pressure of 1x10-’ torr. regulation of high voltage, and reduction cf frictional wind loss and the mechanical vibration. In Introduction addition, elimination of gas handling system may enhance the compactness and the flexibilities for the The recent progress of research and industrial accelerator system. The characteristics and the applications of ion beams require very stable beams operational performance of this vacuum electrostatic with the high energy of around 1 MeV and the current generator have been described in this paper. of a few mA. A candidate of high voltage sources to produce Experimental Apparatus mono-energetic beams is electrostatic generator, which has superior features such as small voltage ripple and The schematic drawins of the vacuum electrostatic small stored energy in the state of ultra high generator is shown in Fig.
    [Show full text]
  • Basic Electrostatics System Model No
    Instruction Manual Manual No. 012-07227E *012-07227* Basic Electrostatics System Model No. ES-9080 Basic Electrostatics System Model No. ES-9080 Table of Contents Equipment List........................................................... 3 Introduction .......................................................... 4-5 Equipment Description .............................................. 5-11 Electrometer...................................................................................................................................5 Electrostatics Voltage Source ........................................................................................................6 Variable Capacitor .........................................................................................................................7 Charge Producers and Proof Plane............................................................................................. 7-8 Proof Plane................................................................................................................................. 8-9 Faraday Ice Pail............................................................................................................................10 Conductive Spheres......................................................................................................................11 Resistor-Capacitor Network Accessory.......................................................................................11 Electrometer Operation and Setup Requirements................12-13
    [Show full text]
  • A Brief History and Review of Accelerators
    A BRIEF HISTORY AND REVIEW OF ACCELERATORS P.J. Bryant CERN, Geneva, Switzerland ABSTRACT The history of accelerators is traced from three separate roots, through a rapid development to the present day. The well-known Livingston chart is used to illustrate how spectacular this development has been with, on average, an increase of one and a half orders of magnitude in energy per decade, since the early thirties. Several present-day accelerators are reviewed along with plans and hopes for the future. 1 . INTRODUCTION High-energy physics research has always been the driving force behind the development of particle accelerators. They started life in physics research laboratories in glass envelopes sealed with varnish and putty with shining electrodes and frequent discharges, but they have long since outgrown this environment to become large-scale facilities offering services to large communities. Although the particle physics community is still the main group, they have been joined by others of whom the synchrotron light users are the largest and fastest growing. There is also an increasing interest in radiation therapy in the medical world and industry has been a long-time user of ion implantation and many other applications. Consequently accelerators now constitute a field of activity in their own right with professional physicists and engineers dedicated to their study, construction and operation. This paper will describe the early history of accelerators, review the important milestones in their development up to the present day and take a preview of future plans and hopes. 2 . HISTORICAL ROOTS The early history of accelerators can be traced from three separate roots.
    [Show full text]
  • Concept of an Accelerator-Driven Advanced Nuclear Energy System
    Article Concept of an Accelerator-Driven Advanced Nuclear Energy System Xuesong Yan, Lei Yang *, Xunchao Zhang and Wenlong Zhan Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China; [email protected] (X.Y.); [email protected] (X.Z.); [email protected] (W.Z.) * Correspondence: [email protected]; Tel.: +86-931-4969-187 Academic Editor: Hiroshi Sekimoto Received: 24 March 2017; Accepted: 10 May 2017; Published: 7 July 2017 Abstract: The utilization of clean energy is a matter of primary importance for sustainable development as well as a vital approach for solving worldwide energy-related issues. If the low utilization rate of nuclear fuel, nuclear proliferation, and insufficient nuclear safety can be solved, nuclear fission energy could be used as a sustainable and low-carbon clean energy form for thousands of years, providing steady and base-load electrical resources. To address these challenges, we propose an accelerator-driven advanced nuclear energy system (ADANES), consisting of a burner system and a fuel recycle system. In ADANES, the ideal utilization rate of nuclear fuel will be >95%, and the final disposal of nuclear waste will be minimized. The design of a high-temperature ceramic reactor makes the burner system safer. Part of fission products (FPs) are removed during the simple reprocessing in the fuel recycle system, significantly reducing the risks of nuclear proliferation of nuclear technology and materials. The ADANES concept integrates nuclear waste transmutation, nuclear fuel breeding, and safety power production, with an ideal closed loop operation of nuclear fission energy, constituting a major innovation of great potential interest for future energy applications.
    [Show full text]
  • Particle Accelerators
    Particle Accelerators By Stephen Lucas The subatomic Shakespeare of St.Neots Purposes of this presentation… To be able to explain how different particle accelerators work. To be able to explain the role of magnetic fields in particle accelerators. How the magnetic force provides the centripetal force in particle accelerators. Why have particle accelerators? They enable similarly charged particles to get close to each other - e.g. Rutherford blasted alpha particles at a thin piece of gold foil, in order to get the positively charged alpha particle near to the nucleus of a gold atom, high energies were needed to overcome the electrostatic force of repulsion. The more energy given to particles, the shorter their de Broglie wavelength (λ = h/mv), therefore the greater the detail that can be investigated using them as a probe e.g. – at the Stanford Linear Accelerator, electrons were accelerated to high energies and smashed into protons and neutrons revealing charge concentrated at three points – quarks. Colliding particles together, the energy is re-distributed producing new particles. The higher the collision energy the larger the mass of the particles that can be produced. E = mc2 The types of particle accelerator Linear Accelerators or a LINAC Cyclotron Synchrotron Basic Principles All accelerators are based on the same principle. A charged particle accelerates between a gap between two electrodes when there is a potential difference between them. Energy transferred, Ek = Charge, C x p.d, V Joules (J) Coulombs (C) Volts (V) Ek = QV Converting to electron volts 1 eV is the energy transferred to an electron when it moves through a potential difference of 1V.
    [Show full text]
  • Particle Accelerator Products for Advanced Research and High-Precision Radiation Therapy Equipment Using Accelerator Technology
    Mitsubishi Heavy Industries Technical Review Vol. 51 No. 3 (September 2014) 54 Particle Accelerator Products for Advanced Research and High-precision Radiation Therapy Equipment using Accelerator Technology Advanced Mechanical Systems Sales & Marketing Group Business Development Department Business Strategy Division Machinery, Equipment & Infrastructure Particle accelerators, which are used for advanced research in fields such as high energy physics and radiation physics, accelerate charged particles (e.g., electrons and protons) to nearly the speed of light at which particles possess high energy. Mitsubishi Heavy Industries, Ltd. (MHI) has provided domestic and overseas research institutions with several types of accelerating cavities or structures, which are the heart of an accelerator. We are also internally developing state-of-the-art accelerator manufacturing technologies. The ultra-compact accelerating structure we have thus developed is mounted on our Vero4DRT high-precision radiation therapy equipment (marketed under the MHI-TM2000 Linear Accelerator System brand name). This report introduces our superconducting accelerating cavities, normal-conducting accelerating structures and radiation therapy equipment as applied products thereof. |1. Superconducting accelerating cavities 1.1 Features Superconducting accelerating cavities can lower electrical resistance to nearly zero by cooling the niobium constituting the cavities down to an extremely low temperature by using of refrigerants such as liquid helium and thereby achieving superconductivity.
    [Show full text]
  • Linear Accelerator for Radioisotope Production
    LA-9144-MS LA-—9144-MS UC-28 and UC-48 Issued: February 1982 DE82 00 9551 A Linear Accelerator for Radioisotope Production L. D. Hansborough R. W. Hamm J. E. Stovail t Los Alamos National Laboratory Los Alamos, New Mexico 87545 A LINEAR ACCELERATOR FOR RADIOISOTOPE PRODUCTION by L. D. Hansborough, P.. W. Harnm, and J. E. Stovall ABSTRACT A 200- to 500-MA source of 70- to 90-MeV protons would be a valuable asset to the nuclear medicine program. A linear accelerator (linac) can achieve this performance, and it can be extended to even higher energies and currents. Variable energy and current options are available. A 70-MeV linac is described, based on recent innovations in linear accelerator technology; it would be 27.3 m long and cost ~?6 million. By operating the radio-frequency (rf) power system at a level necess.-.ry to produce a 500-uA bedm current, the cost of power deposited in the radioisotope- production target is comparable with existing cyclotrons. If the rf-power system is operated at full power, the same accelerator is capable of producing an 1140-uA beam, and the cost per beam watt on the target is less than half that of comparable cyclotrons. I. MEDICAL RADIOISOTOPE PRODUCTION Nuclear medicine is a major medical specialty that provides noninvasive, cost-effective, dynamic-function information that is clinically useful in diag¬ nosing human diseases. Reactors have produced radioactive isotopes of practi¬ cally every element. Clever techniques have been developed for recovering the high specific-activity products from uranium fission (Mo, I, and ^Xe) and from fast-neutron-induced (n,p) and (n,a) reactions ( K, Mn, Co, Cu, 132 Cs, etc.).
    [Show full text]
  • 01. Franklin Intro 9/04
    Franklin and Electrostatics- Ben Franklin as my Lab Partner A Workshop on Franklin’s Experiments in Electrostatics Developed at the Wright Center for Innovative Science Teaching Tufts University Medford MA 02155 by Robert A. Morse, Ph.D. ©2004 Sept 2004 Benjamin Franklin observing his lightning alarm. Described in Section VII. Engraving after the painting by Mason Chamberlin, R. A. Reproduced from Bigelow, 1904 Vol. VII Franklin and Electrostatics version 1.3 ©2004 Robert A. Morse Wright Center for Science Teaching, Tufts University Section I- page 1 Copyright and reproduction Copyright 2004 by Robert A. Morse, Wright Center for Science Education, Tufts University, Medford, MA. Quotes from Franklin and others are in the public domain, as are images labeled public domain. These materials may be reproduced freely for educational and individual use and extracts may be used with acknowledgement and a copy of this notice.These materials may not be reproduced for commercial use or otherwise sold without permission from the copyright holder. The materials are available on the Wright Center website at www.tufts.edu/as/wright_center/ Acknowledgements Rodney LaBrecque, then at Milton Academy, wrote a set of laboratory activities on Benjamin Franklin’s experiments, which was published as an appendix to my 1992 book, Teaching about Electrostatics, and I thank him for directing my attention to Franklin’s writing and the possibility of using his experiments in teaching. I would like to thank the Fondation H. Dudley Wright and the Wright Center for Innovative Science Teaching at Tufts University for the fellowship support and facilities that made this work possible.
    [Show full text]
  • Evidence Report: Risk of Acute and Late Central Nervous System
    Risk of Acute (In-flight) or Late Central Nervous System Effects from Radiation Exposure Evidence Report: Risk of Acute and Late Central Nervous System Effects from Radiation Exposure Human Research Program Space Radiation Program Element Approved for Public Release: April 6, 2016 National Aeronautics and Space Administration Lyndon B. Johnson Space Center Houston, Texas 1 Risk of Acute (In-flight) or Late Central Nervous System Effects from Radiation Exposure CURRENT CONTRIBUTING AUTHORS: Gregory A. Nelson Loma Linda University/ NASA IPA NASA Johnson Space Center, Houston, TX Lisa Simonsen NASA Langley Research Center, Hampton, VA Janice L. Huff Universities Space Research Association, Houston, TX PREVIOUS CONTRIBUTING AUTHORS: Francis A. Cucinotta NASA Johnson Space Center, Houston, TX Janice L. Huff Universities Space Research Association, Houston, TX Myung-Hee Y. Kim Universities Space Research Association, Houston, TX Janapriya Saha Universities Space Research Association, Houston, TX Minli Wang Universities Space Research Association, Houston, TX Frank M. Sulzman Universities Space Research Association, Houston, TX Reference for original report: Human Health and Performance Risks of Space Exploration Missions, (Jancy C. McPhee and John B. Charles, editors), NASA SP-2009- 3405, 2009. Slack KJ, Shea C, Leveton LB, Whitmire AM, Schmidt LL (2009) Risk of Behavioral and Psychiatric Conditions In: McPhee JC, Charles JB (eds) Human Health and Performance Risks of Space Exploration Missions, NASA SP-2009-3405 2 Risk of Acute (In-flight) or Late Central Nervous System Effects from Radiation Exposure TABLE OF CONTENTS: I. PRD RISK TITLE: RISK OF ACUTE (IN-FLIGHT) AND LATE CENTRAL NERVOUS SYSTEM EFFECTS FROM RADIATION EXPOSURE ........................... 5 II. EXECUTIVE SUMMARY ................................................................................................
    [Show full text]