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Compton Scattering from the Deuteron at Low Energies
SE0200264 LUNFD6-NFFR-1018 Compton Scattering from the Deuteron at Low Energies Magnus Lundin Department of Physics Lund University 2002 W' •sii" Compton spridning från deuteronen vid låga energier (populärvetenskaplig sammanfattning på svenska) Vid Compton spridning sprids fotonen elastiskt, dvs. utan att förlora energi, mot en annan partikel eller kärna. Kärnorna som användes i detta försök består av en proton och en neutron (sk. deuterium, eller tungt väte). Kärnorna bestrålades med fotoner av kända energier och de spridda fo- tonerna detekterades mha. stora Nal-detektorer som var placerade i olika vinklar runt strålmålet. Försöket utfördes under 8 veckor och genom att räkna antalet fotoner som kärnorna bestålades med och antalet spridda fo- toner i de olika detektorerna, kan sannolikheten för att en foton skall spridas bestämmas. Denna sannolikhet jämfördes med en teoretisk modell som beskriver sannolikheten för att en foton skall spridas elastiskt mot en deuterium- kärna. Eftersom protonen och neutronen består av kvarkar, vilka har en elektrisk laddning, kommer dessa att sträckas ut då de utsätts för ett elek- triskt fält (fotonen), dvs. de polariseras. Värdet (sannolikheten) som den teoretiska modellen ger, beror på polariserbarheten hos protonen och neu- tronen i deuterium. Genom att beräkna sannolikheten för fotonspridning för olika värden av polariserbarheterna, kan man se vilket värde som ger bäst överensstämmelse mellan modellen och experimentella data. Det är speciellt neutronens polariserbarhet som är av intresse, och denna kunde bestämmas i detta arbete. Organization Document name LUND UNIVERSITY DOCTORAL DISSERTATION Department of Physics Date of issue 2002.04.29 Division of Nuclear Physics Box 118 Sponsoring organization SE-22100 Lund Sweden Author (s) Magnus Lundin Title and subtitle Compton Scattering from the Deuteron at Low Energies Abstract A series of three Compton scattering experiments on deuterium have been performed at the high-resolution tagged-photon facility MAX-lab located in Lund, Sweden. -
Timeline / 1860 to 1900
Timeline / 1860 to 1900 Date Country Theme 1860 - 1900 Tunisia Cities And Urban Spaces Following development of the Port of La Goulette, new districts relating to trade and industrial activities are born. The neighbourhood is given the name of “Little Sicily”, which is suggestive of its role as host to a poor immigrant population mainly from southern Italy. 1860 Tunisia Great Inventions Of The 19th Century The restoration of the Aqueduct of Zaghouan is completed, running water arrives in Tunis. 1860 - 1863 Tunisia Economy And Trade Restoration of the Zaghouan Aqueduct, Tunisia’s largest water-service network, allows supply to the capital and its suburbs. 1860 Romania Fine And Applied Arts 7 November: on the initiative of painter Gheorghe Panaitescu-Bardasare, a School of Fine Arts and an art gallery are founded in Ia#i. 1860 France Travelling First trip by Napoleon III to Algeria; the second will take place in 1865. 1860 - 1870 Jordan Reforms And Social Changes By the 1860s, population density has decreased drastically. The border of the sawn cultivated land had been pushed westwards under the pressure of the nomadic tribes from the east. Several reasons are suggested for this decline, including maladministration and the taxation policies of the Ottoman Empire. Some of the regions south of Ajlun, including Amman area, and along the escarpment of the Jordan valley were almost completely abandoned. Recovery starts during the last quarter of the 19th century. 1860 Italy Cities And Urban Spaces The unification of Italy leads to urban expansion outside the old city walls, which have lost their defensive value. -
The Equation of Radiative Transfer How Does the Intensity of Radiation Change in the Presence of Emission and / Or Absorption?
The equation of radiative transfer How does the intensity of radiation change in the presence of emission and / or absorption? Definition of solid angle and steradian Sphere radius r - area of a patch dS on the surface is: dS = rdq ¥ rsinqdf ≡ r2dW q dS dW is the solid angle subtended by the area dS at the center of the † sphere. Unit of solid angle is the steradian. 4p steradians cover whole sphere. ASTR 3730: Fall 2003 Definition of the specific intensity Construct an area dA normal to a light ray, and consider all the rays that pass through dA whose directions lie within a small solid angle dW. Solid angle dW dA The amount of energy passing through dA and into dW in time dt in frequency range dn is: dE = In dAdtdndW Specific intensity of the radiation. † ASTR 3730: Fall 2003 Compare with definition of the flux: specific intensity is very similar except it depends upon direction and frequency as well as location. Units of specific intensity are: erg s-1 cm-2 Hz-1 steradian-1 Same as Fn Another, more intuitive name for the specific intensity is brightness. ASTR 3730: Fall 2003 Simple relation between the flux and the specific intensity: Consider a small area dA, with light rays passing through it at all angles to the normal to the surface n: n o In If q = 90 , then light rays in that direction contribute zero net flux through area dA. q For rays at angle q, foreshortening reduces the effective area by a factor of cos(q). -
Slides for Statistics, Precision, and Solid Angle
Slides for Statistics, Precision, and Solid Angle 22.01 – Intro to Radiation October 14, 2015 22.01 – Intro to Ionizing Radiation Precision etc., Slide 1 Solid Angles, Dose vs. Distance • Dose decreases with the inverse square of distance from the source: 1 퐷표푠푒 ∝ 푟2 • This is due to the decrease in solid angle subtended by the detector, shielding, person, etc. absorbing the radiation 22.01 – Intro to Ionizing Radiation Precision etc., Slide 2 Solid Angles, Dose vs. Distance • The solid angle is defined in steradians, and given the symbol Ω. • For a rectangle with width w and length l, at a distance r from a point source: 푤푙 Ω = 4푎푟푐푡푎푛 2푟 4푟2 + w2 + 푙2 • A full sphere has 4π steradians (Sr) 22.01 – Intro to Ionizing Radiation Precision etc., Slide 3 Solid Angles, Dose vs. Distance http://www.powerfromthesun.net/Book/chapter02/chapter02.html • Total luminance (activity) of a source is constant, but the flux through a surface decreases with distance Courtesy of William B. Stine. Used with permission. 22.01 – Intro to Ionizing Radiation Precision etc., Slide 4 Exponential Gamma Attenuation • Gamma sources are attenuated exponentially according to this formula: Initial intensity Mass attenuation coefficient 흁 Distance through − 흆 흆풙 푰 = 푰ퟎ풆 material Transmitted intensity Material density • Attenuation means removal from a narrowly collimated beam by any means 22.01 – Intro to Ionizing Radiation Precision etc., Slide 5 Exponential Gamma Attenuation Look up values in NIST x-ray attenuation tables: http://www.nist.gov/pml/data/xraycoef/ Initial -
General Method of Solid Angle Calculation Using Attitude Kinematics
1 1 General method of solid angle calculation using attitude kinematics 2 3 Russell P. Patera1 4 351 Meredith Way, Titusville, FL 32780, United States 5 6 Abstract 7 A general method to compute solid angle is developed that is based on Ishlinskii’s theorem, which specifies the 8 relationship between the attitude transformation of an axis that completely slews about a conical region and the 9 solid angle of the enclosed region. After an axis slews about a conical region and returns to its initial orientation, it 10 will have rotated by an angle precisely equal to the enclosed solid angle. The rotation is the magnitude of the 11 Euler rotation vector of the attitude transformation produced by the slewing motion. Therefore, the solid angle 12 can be computed by first computing the attitude transformation of an axis that slews about the solid angle region 13 and then computing the solid angle from the attitude transformation. This general method to compute the solid 14 angle involves approximating the solid angle region’s perimeter as seen from the source, with a discrete set of 15 points on the unit sphere, which join a set of great circle arcs that approximate the perimeter of the region. Pivot 16 Parameter methodology uses the defining set of points to compute the attitude transformation of the axis due to 17 its slewing motion about the enclosed solid angle region. The solid angle is the magnitude of the resulting Euler 18 rotation vector representing the transformation. The method was demonstrated by comparing results to 19 published results involving the solid angles of a circular disk radiation detector with respect to point, line and disk 20 shaped radiation sources. -
Wilhelm Ritter: Teacher of Maillart and Ammann
Wilhelm Ritter: teacher of Maillart and Ammann Autor(en): Billington, David P. Objekttyp: Article Zeitschrift: Ingénieurs et architectes suisses Band (Jahr): 113 (1987) Heft 7 PDF erstellt am: 05.10.2021 Persistenter Link: http://doi.org/10.5169/seals-76366 Nutzungsbedingungen Die ETH-Bibliothek ist Anbieterin der digitalisierten Zeitschriften. Sie besitzt keine Urheberrechte an den Inhalten der Zeitschriften. Die Rechte liegen in der Regel bei den Herausgebern. Die auf der Plattform e-periodica veröffentlichten Dokumente stehen für nicht-kommerzielle Zwecke in Lehre und Forschung sowie für die private Nutzung frei zur Verfügung. Einzelne Dateien oder Ausdrucke aus diesem Angebot können zusammen mit diesen Nutzungsbedingungen und den korrekten Herkunftsbezeichnungen weitergegeben werden. Das Veröffentlichen von Bildern in Print- und Online-Publikationen ist nur mit vorheriger Genehmigung der Rechteinhaber erlaubt. Die systematische Speicherung von Teilen des elektronischen Angebots auf anderen Servern bedarf ebenfalls des schriftlichen Einverständnisses der Rechteinhaber. Haftungsausschluss Alle Angaben erfolgen ohne Gewähr für Vollständigkeit oder Richtigkeit. Es wird keine Haftung übernommen für Schäden durch die Verwendung von Informationen aus diesem Online-Angebot oder durch das Fehlen von Informationen. Dies gilt auch für Inhalte Dritter, die über dieses Angebot zugänglich sind. Ein Dienst der ETH-Bibliothek ETH Zürich, Rämistrasse 101, 8092 Zürich, Schweiz, www.library.ethz.ch http://www.e-periodica.ch CHRISTIAN MENN Ingénieurs el architectes suisses n" 7 26 mars 1987 Tableau 1. — Amplitudes maximales des variations de températures uniformes les ponts selon différentes sources. pour Bibliographie à Taa [°C] [1] J accoud, J.-P. Gradients de tempéra¬ dans les et Ponts en bétons Ponts mixtes Ponts en acier ture ponts. -
FORM and FORCE 7-10 October 2019, Barcelona, Spain
60th Anniversary Symposium of the International Association for Shell and Spatial Structures IASS Symposium 2019 9th International Conference on Textile Composites and Inflatable Structures Structural Membranes 2019 FORM and FORCE 7-10 October 2019, Barcelona, Spain Carlos Lázaro, Kai-Uwe Bletzinger and Eugenio Oñate (Eds.) IASS Symposium 2019 60th Anniversary Symposium of the International Association for Shell and Spatial Structures Structural Membranes 2019 9th International Conference on Textile Composites and Inflatable Structures FORM and FORCE Barcelona, Spain October 7 - 10, 2019 A publication of: International Centre for Numerical Methods in Engineering (CIMNE) Barcelona, Spain ISBN: 978-84-121101-0-4 Printed by: Artes Gráficas Torres S.L., Huelva 9, 08940 Cornellà de Llobregat, Spain SUMMARY SUMMARY INVITED SESSIONS IS - Actual Structural Behavior of Thin Shells (IASS WG 5) ...................................... 45 IS - Adaptive Lightweight Structures .................................................................. 68 IS - Additive Manufacturing of Architectural Components........................................ 87 IS - Analysis and Design of Adaptive Structures ...................................................121 IS - Bio-inspiration for Structural Forms + Fractal and Form ...................................129 IS - Celebrating the Work of Mike Barnes ............................................................145 IS - Constructive Geometry for Structural Design (IASS WG 15) ...............................175 IS - Contemporary -
From the Geometry of Foucault Pendulum to the Topology of Planetary Waves
From the geometry of Foucault pendulum to the topology of planetary waves Pierre Delplace and Antoine Venaille Univ Lyon, Ens de Lyon, Univ Claude Bernard, CNRS, Laboratoire de Physique, F-69342 Lyon, France Abstract The physics of topological insulators makes it possible to understand and predict the existence of unidirectional waves trapped along an edge or an interface. In this review, we describe how these ideas can be adapted to geophysical and astrophysical waves. We deal in particular with the case of planetary equatorial waves, which highlights the key interplay between rotation and sphericity of the planet, to explain the emergence of waves which propagate their energy only towards the East. These minimal in- gredients are precisely those put forward in the geometric interpretation of the Foucault pendulum. We discuss this classic example of mechanics to introduce the concepts of holonomy and vector bundle which we then use to calculate the topological properties of equatorial shallow water waves. Résumé La physique des isolants topologiques permet de comprendre et prédire l’existence d’ondes unidirectionnelles piégées le long d’un bord ou d’une interface. Nous décrivons dans cette revue comment ces idées peuvent être adaptées aux ondes géophysiques et astrophysiques. Nous traitons en parti- culier le cas des ondes équatoriales planétaires, qui met en lumière les rôles clés combinés de la rotation et de la sphéricité de la planète pour expliquer l’émergence d’ondes qui ne propagent leur énergie que vers l’est. Ces ingré- dients minimaux sont précisément ceux mis en avant dans l’interprétation géométrique du pendule de Foucault. -
Radiometry and Photometry
Radiometry and Photometry Wei-Chih Wang Department of Power Mechanical Engineering National TsingHua University W. Wang Materials Covered • Radiometry - Radiant Flux - Radiant Intensity - Irradiance - Radiance • Photometry - luminous Flux - luminous Intensity - Illuminance - luminance Conversion from radiometric and photometric W. Wang Radiometry Radiometry is the detection and measurement of light waves in the optical portion of the electromagnetic spectrum which is further divided into ultraviolet, visible, and infrared light. Example of a typical radiometer 3 W. Wang Photometry All light measurement is considered radiometry with photometry being a special subset of radiometry weighted for a typical human eye response. Example of a typical photometer 4 W. Wang Human Eyes Figure shows a schematic illustration of the human eye (Encyclopedia Britannica, 1994). The inside of the eyeball is clad by the retina, which is the light-sensitive part of the eye. The illustration also shows the fovea, a cone-rich central region of the retina which affords the high acuteness of central vision. Figure also shows the cell structure of the retina including the light-sensitive rod cells and cone cells. Also shown are the ganglion cells and nerve fibers that transmit the visual information to the brain. Rod cells are more abundant and more light sensitive than cone cells. Rods are 5 sensitive over the entire visible spectrum. W. Wang There are three types of cone cells, namely cone cells sensitive in the red, green, and blue spectral range. The approximate spectral sensitivity functions of the rods and three types or cones are shown in the figure above 6 W. Wang Eye sensitivity function The conversion between radiometric and photometric units is provided by the luminous efficiency function or eye sensitivity function, V(λ). -
D-BAUG Jahresbericht 2016 Annual Report 2016
D-BAUG Jahresbericht 2016 Annual Report 2016 New perspectives DBAUG Departement Bau, Umwelt und Geomatik Department of Civil, Environmental and Geomatic Engineering 10 12 22 Prof. Willi H. Hager Emeritierung/Pensionierung ETH-Ehrendoktor für Max Ernst Meyer Bauingenieur und ETH Professor Carl Culmann 24 34 40 Das «Goldene Dreirad» für Prof. Lorenz Hurni Master Leistungsstipendien: Viviane Furrer D-BAUG Studenten in Havanna 52 55 73 Interview mit Prof. Thomas Vogel Gotthard Basis Tunnel: Zwei ETH Alumni berichten Neuer 3D-Atlas für Kartenliebhaber INHALT Vorwort i Gotthard Basis Tunnel: Zwei ETH Alumni berichten über ihre Erfahrungen 55 FAKULTÄT UND CAMPUS Studierendenzahlen 60 Neu am D-BAUG 2 FORSCHUNG UND LEHRE Emeritierungen/Pensionierungen 10 Eröffnung des Gotthard Basistunnels 64 ETH-Ehrendoktor für Brückenbauer Max Ernst Meyer 12 Gottardino Event 68 Stephan Pfister, IfU 14 Wo im Gotthard-Basistunnel ETH und D-BAUG drinsteckt 70 Umweltbewertung der globalen Landwirtschaftlichen Produktion 16 Neuer 3D-Atlas für Kartenliebhaber 74 Othmar Frei, IfU 18 Mit Holz und Robotern zur eigenen Firma 78 Entwicklung eines fahrzeuggestützten Spin-off Swiss Wood Solutions AG 80 abbildenden Radarinterferometers 20 Frühwarnsystem für Lawinen und Carl Culmann (1821–1881) 22 Europäisches Patent 82 Motivieren mit Instinkt 24 FAKTEN UND ZAHLEN Goldene Eule des VSETH 26 Institute und Professuren 86 “International Map Year”: Aktivitäten in der Schweiz 28 Fachgebiete innerhalb der strategischen Schwerpunkte 88 DONATOREN UND TALENTE Organisation D-BAUG 92 Donatoren D-BAUG 2016 32 Advisory Board und Fakultät 93 Master Leistungsstipendien Kennzahlen 94 (ESOP und MSP) 34 Ehrungen 96 Kontakte 99 STUDIERENDE UND ALUMNI Stab 100 AIV BauingenieurinnenFORUM 2016 36 Havanna Sommer Schule 38 KLIMASCHUTZPROJEKT 102 Eindrücke von Havanna aus Sicht der D-BAUG Studierenden 40 IMPRESSUM 103 Masterarbeit MIT, Cambridge, MA/USA 44 Masterreise nach China 48 LAGEPLAN 104 Interview mit Prof. -
Invariance Properties of the Dirac Monopole
fcs.- 0; /A }Ю-ц-^. KFKI-75-82 A. FRENKEL P. HRASKÓ INVARIANCE PROPERTIES OF THE DIRAC MONOPOLE Hungarian academy of Sciences CENTRAL RESEARCH INSTITUTE FOR PHYSICS BUDAPEST L KFKI-75-S2 INVARIÄHCE PROPERTIES OF THE DIRAC MONOPOLE A. Frenkel and P. Hraskó High Energy Physics Department Central Research Institute for Physics, Budapest, Hungary ISBN 963 371 094 4 ABSTRACT The quantum mechanical motion of a spinless electron in the external field of a magnetic monopolé of magnetic charge v is investigated. Xt is shown that Dirac's quantum condition 2 ue(hc)'1 • n for the string being unobservable ensures rotation invarlance and correct space reflection proper ties for any integer value of n. /he rotation and space reflection operators are found and their group theoretical properties are discussed, A method for constructing conserved quantities In the case when the potential ie not explicitly invariant under the symmetry operation is also presented and applied to the discussion of the angular momentum of the electron-monopole system. АННОТАЦИЯ Рассматривается кваитоаомеханическое движение бесспинового элект рона во внешнем поле монополя с Магнитки« зарядом и. Доказывается» что кван товое условие Дирака 2ув(пс)-1 •> п обеспечивает не только немаолтваемость стру ны »но и инвариантность при вращении и правильные свойства при пространственных отражениях для любого целого п. Даются операторы времени* я отражения, и об суждаются их групповые свойства. Указан также метод построения интегралов движения в случае, когда потенциал не является язно инвариантным по отношению операции симметрии, и этот метод применяется при изучении углового момента сис темы электрон-монопопь. KIVONAT A spin nélküli elektron kvantummechanikai viselkedését vizsgáljuk u mágneses töltésű monopolus kttlsö terében. -
International System of Units (Si)
[TECHNICAL DATA] INTERNATIONAL SYSTEM OF UNITS( SI) Excerpts from JIS Z 8203( 1985) 1. The International System of Units( SI) and its usage 1-3. Integer exponents of SI units 1-1. Scope of application This standard specifies the International System of Units( SI) and how to use units under the SI system, as well as (1) Prefixes The multiples, prefix names, and prefix symbols that compose the integer exponents of 10 for SI units are shown in Table 4. the units which are or may be used in conjunction with SI system units. Table 4. Prefixes 1 2. Terms and definitions The terminology used in this standard and the definitions thereof are as follows. - Multiple of Prefix Multiple of Prefix Multiple of Prefix (1) International System of Units( SI) A consistent system of units adopted and recommended by the International Committee on Weights and Measures. It contains base units and supplementary units, units unit Name Symbol unit Name Symbol unit Name Symbol derived from them, and their integer exponents to the 10th power. SI is the abbreviation of System International d'Unites( International System of Units). 1018 Exa E 102 Hecto h 10−9 Nano n (2) SI units A general term used to describe base units, supplementary units, and derived units under the International System of Units( SI). 1015 Peta P 10 Deca da 10−12 Pico p (3) Base units The units shown in Table 1 are considered the base units. 1012 Tera T 10−1 Deci d 10−15 Femto f (4) Supplementary units The units shown in Table 2 below are considered the supplementary units.