Standard Model of Particle Physics, Or Beyond?
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The Five Common Particles
The Five Common Particles The world around you consists of only three particles: protons, neutrons, and electrons. Protons and neutrons form the nuclei of atoms, and electrons glue everything together and create chemicals and materials. Along with the photon and the neutrino, these particles are essentially the only ones that exist in our solar system, because all the other subatomic particles have half-lives of typically 10-9 second or less, and vanish almost the instant they are created by nuclear reactions in the Sun, etc. Particles interact via the four fundamental forces of nature. Some basic properties of these forces are summarized below. (Other aspects of the fundamental forces are also discussed in the Summary of Particle Physics document on this web site.) Force Range Common Particles It Affects Conserved Quantity gravity infinite neutron, proton, electron, neutrino, photon mass-energy electromagnetic infinite proton, electron, photon charge -14 strong nuclear force ≈ 10 m neutron, proton baryon number -15 weak nuclear force ≈ 10 m neutron, proton, electron, neutrino lepton number Every particle in nature has specific values of all four of the conserved quantities associated with each force. The values for the five common particles are: Particle Rest Mass1 Charge2 Baryon # Lepton # proton 938.3 MeV/c2 +1 e +1 0 neutron 939.6 MeV/c2 0 +1 0 electron 0.511 MeV/c2 -1 e 0 +1 neutrino ≈ 1 eV/c2 0 0 +1 photon 0 eV/c2 0 0 0 1) MeV = mega-electron-volt = 106 eV. It is customary in particle physics to measure the mass of a particle in terms of how much energy it would represent if it were converted via E = mc2. -
Fundamentals of Particle Physics
Fundamentals of Par0cle Physics Particle Physics Masterclass Emmanuel Olaiya 1 The Universe u The universe is 15 billion years old u Around 150 billion galaxies (150,000,000,000) u Each galaxy has around 300 billion stars (300,000,000,000) u 150 billion x 300 billion stars (that is a lot of stars!) u That is a huge amount of material u That is an unimaginable amount of particles u How do we even begin to understand all of matter? 2 How many elementary particles does it take to describe the matter around us? 3 We can describe the material around us using just 3 particles . 3 Matter Particles +2/3 U Point like elementary particles that protons and neutrons are made from. Quarks Hence we can construct all nuclei using these two particles -1/3 d -1 Electrons orbit the nuclei and are help to e form molecules. These are also point like elementary particles Leptons We can build the world around us with these 3 particles. But how do they interact. To understand their interactions we have to introduce forces! Force carriers g1 g2 g3 g4 g5 g6 g7 g8 The gluon, of which there are 8 is the force carrier for nuclear forces Consider 2 forces: nuclear forces, and electromagnetism The photon, ie light is the force carrier when experiencing forces such and electricity and magnetism γ SOME FAMILAR THE ATOM PARTICLES ≈10-10m electron (-) 0.511 MeV A Fundamental (“pointlike”) Particle THE NUCLEUS proton (+) 938.3 MeV neutron (0) 939.6 MeV E=mc2. Einstein’s equation tells us mass and energy are equivalent Wave/Particle Duality (Quantum Mechanics) Einstein E -
Introduction to Particle Physics
SFB 676 – Projekt B2 Introduction to Particle Physics Christian Sander (Universität Hamburg) DESY Summer Student Lectures – Hamburg – 20th July '11 Outline ● Introduction ● History: From Democrit to Thomson ● The Standard Model ● Gauge Invariance ● The Higgs Mechanism ● Symmetries … Break ● Shortcomings of the Standard Model ● Physics Beyond the Standard Model ● Recent Results from the LHC ● Outlook Disclaimer: Very personal selection of topics and for sure many important things are left out! 20th July '11 Introduction to Particle Physics 2 20th July '11 Introduction to Particle PhysicsX Files: Season 2, Episode 233 … für Chester war das nur ein Weg das Geld für das eigentlich theoretische Zeugs aufzubringen, was ihn interessierte … die Erforschung Dunkler Materie, …ähm… Quantenpartikel, Neutrinos, Gluonen, Mesonen und Quarks. Subatomare Teilchen Die Geheimnisse des Universums! Theoretisch gesehen sind sie sogar die Bausteine der Wirklichkeit ! Aber niemand weiß, ob sie wirklich existieren !? 20th July '11 Introduction to Particle PhysicsX Files: Season 2, Episode 234 The First Particle Physicist? By convention ['nomos'] sweet is sweet, bitter is bitter, hot is hot, cold is cold, color is color; but in truth there are only atoms and the void. Democrit, * ~460 BC, †~360 BC in Abdera Hypothesis: ● Atoms have same constituents ● Atoms different in shape (assumption: geometrical shapes) ● Iron atoms are solid and strong with hooks that lock them into a solid ● Water atoms are smooth and slippery ● Salt atoms, because of their taste, are sharp and pointed ● Air atoms are light and whirling, pervading all other materials 20th July '11 Introduction to Particle Physics 5 Corpuscular Theory of Light Light consist out of particles (Newton et al.) ↕ Light is a wave (Huygens et al.) ● Mainly because of Newtons prestige, the corpuscle theory was widely accepted (more than 100 years) Sir Isaac Newton ● Failing to describe interference, diffraction, and *1643, †1727 polarization (e.g. -
Associated Charged Higgs Boson and Squark Production in the NUHM Model
UPTEC F10 010 Examensarbete 30 hp Februari 2010 Associated charged Higgs boson and squark production in the NUHM model Gustav Lund Abstract Associated charged Higgs boson and squark production in the NUHM model Gustav Lund Teknisk- naturvetenskaplig fakultet UTH-enheten Conventional searches for the charged Higgs boson using its production in association with Standard Model (SM) quarks is notoriously weak in the mid-tanB range. Hoping Besöksadress: to find an alternate channel to fill this gap, the production of the charged Higgs boson Ångströmlaboratoriet Lägerhyddsvägen 1 in association with supersymmetric squarks is studied. Using Monte Carlo generators Hus 4, Plan 0 the production at the LHC is simulated within the non universal Higgs mass model (NUHM). If the six parameters of the model (m0, m1/2, A0, tanB, u, mA) induce small Postadress: masses of the stop, sbottom and charged Higgs, the production cross section can be Box 536 751 21 Uppsala of the order pb. Through scans of the input parameter the cross section is maximized, with the requirement that the stop decays directly to a neutralino - Telefon: simplifying detection, in the point (m0, m1/2, A0, tanB, u, mA) = (190, 187, -1147, 018 – 471 30 03 179, 745, 13.2) where the cross section is 559 fb. Telefax: 018 – 471 30 00 The production is compared to the irreducible backgrounds stop, stop, t, tbar and t, tbar + 2 jets. The former poses no severe constraints and can be easily removed Hemsida: using appropriate cuts. The latter, SM background, has a cross section almost 1000 http://www.teknat.uu.se/student times larger and strong cuts must be imposed to suppress it. -
Read About the Particle Nature of Matter
READING MATERIAL Read About the Particle Nature of Matter PARTICLES OF MATTER DEFINITION Matter is anything that has weight and takes up space. A particle is the smallest possible unit of matter. Understanding that matter is made of tiny particles too small to be seen can help us understand the behavior and properties of matter. To better understand how the 3 states of matter work…. LET’S BREAK IT DOWN! All matter is made of particles that are too small to be seen. Everything you can see and touch is made of matter. It is all the “stuff” in the universe. Things that are not made of matter include energy, and ideas like peace and love. Matter is made up of small particles that are too small to be seen, even with a powerful microscope. They are so small that you would have to put about 100,000 particles in a line to equal the width of a human hair! Page 1 The arrangement of particles determines the state of matter. Particles are arranged and move differently in each state of matter. Solids contain particles that are tightly packed, with very little space between particles. If an object can hold its own shape and is difficult to compress, it is a solid. Liquids contain particles that are more loosely packed than solids, but still closely packed compared to gases. Particles in liquids are able to slide past each other, or flow, to take the shape of their container. Particles are even more spread apart in gases. Gases will fill any container, but if they are not in a container, they will escape into the air. -
Quantum Field Theory*
Quantum Field Theory y Frank Wilczek Institute for Advanced Study, School of Natural Science, Olden Lane, Princeton, NJ 08540 I discuss the general principles underlying quantum eld theory, and attempt to identify its most profound consequences. The deep est of these consequences result from the in nite number of degrees of freedom invoked to implement lo cality.Imention a few of its most striking successes, b oth achieved and prosp ective. Possible limitation s of quantum eld theory are viewed in the light of its history. I. SURVEY Quantum eld theory is the framework in which the regnant theories of the electroweak and strong interactions, which together form the Standard Mo del, are formulated. Quantum electro dynamics (QED), b esides providing a com- plete foundation for atomic physics and chemistry, has supp orted calculations of physical quantities with unparalleled precision. The exp erimentally measured value of the magnetic dip ole moment of the muon, 11 (g 2) = 233 184 600 (1680) 10 ; (1) exp: for example, should b e compared with the theoretical prediction 11 (g 2) = 233 183 478 (308) 10 : (2) theor: In quantum chromo dynamics (QCD) we cannot, for the forseeable future, aspire to to comparable accuracy.Yet QCD provides di erent, and at least equally impressive, evidence for the validity of the basic principles of quantum eld theory. Indeed, b ecause in QCD the interactions are stronger, QCD manifests a wider variety of phenomena characteristic of quantum eld theory. These include esp ecially running of the e ective coupling with distance or energy scale and the phenomenon of con nement. -
Do About Half the Top Quarks at FNAL Come from Gluino Decays?
ANL–HEP–PR–96–43 UM–TH–96–06 May 1996 Do About Half the Top Quarks at FNAL Come From Gluino Decays? G. L. Kane† Randall Laboratory of Physics University of Michigan Ann Arbor, MI 48104 and S. Mrenna‡ High Energy Physics Division Argonne National Laboratory Argonne, IL 60439 Abstract We argue that it is possible to make a consistent picture of FNAL data including the production and decay of gluinos and squarks. The additional cross section is several pb, about the size of that for Standard Model (SM) top quark pair production. If the stop squark mass is small enough, about half of the top quarks decay to stop squarks, and the loss of SM top quark pair production rate is compensated by the supersymmet- ric processes. This behavior is consistent with the reported top quark decay rates in various modes and other aspects of the data, and suggests several other possible decay signatures. This picture can be tested easily with more data, perhaps even with the data in hand, and demonstrates the potential power of a hadron collider to determine supersymmetric parameters. It also has implications for the top mass measurement and the interpretation of the LEP Rb excess. PAC codes: 12.60.Jv, 12.15.Mm, 14.65.Ha, 14.80.L †[email protected] ‡[email protected] 1 Introduction While there is still no compelling experimental evidence that nature is supersymmetric on the weak scale, there have been recent reports of data that encourage this view. The most explicit is an event in CDF [1] that does not have a probable SM interpretation, and can naturally be explained as selectron pair production[2, 3]. -
SHELDON LEE GLASHOW Lyman Laboratory of Physics Harvard University Cambridge, Mass., USA
TOWARDS A UNIFIED THEORY - THREADS IN A TAPESTRY Nobel Lecture, 8 December, 1979 by SHELDON LEE GLASHOW Lyman Laboratory of Physics Harvard University Cambridge, Mass., USA INTRODUCTION In 1956, when I began doing theoretical physics, the study of elementary particles was like a patchwork quilt. Electrodynamics, weak interactions, and strong interactions were clearly separate disciplines, separately taught and separately studied. There was no coherent theory that described them all. Developments such as the observation of parity violation, the successes of quantum electrodynamics, the discovery of hadron resonances and the appearance of strangeness were well-defined parts of the picture, but they could not be easily fitted together. Things have changed. Today we have what has been called a “standard theory” of elementary particle physics in which strong, weak, and electro- magnetic interactions all arise from a local symmetry principle. It is, in a sense, a complete and apparently correct theory, offering a qualitative description of all particle phenomena and precise quantitative predictions in many instances. There is no experimental data that contradicts the theory. In principle, if not yet in practice, all experimental data can be expressed in terms of a small number of “fundamental” masses and cou- pling constants. The theory we now have is an integral work of art: the patchwork quilt has become a tapestry. Tapestries are made by many artisans working together. The contribu- tions of separate workers cannot be discerned in the completed work, and the loose and false threads have been covered over. So it is in our picture of particle physics. Part of the picture is the unification of weak and electromagnetic interactions and the prediction of neutral currents, now being celebrated by the award of the Nobel Prize. -
Two Tests of New Physics Using Top Quarks at the CMS Experiment
UC San Diego UC San Diego Electronic Theses and Dissertations Title Two Tests of New Physics Using Top Quarks at the CMS Experiment Permalink https://escholarship.org/uc/item/4118h880 Author Klein, Daniel Publication Date 2018 Peer reviewed|Thesis/dissertation eScholarship.org Powered by the California Digital Library University of California UNIVERSITY OF CALIFORNIA SAN DIEGO Two Tests of New Physics Using Top Quarks at the CMS Experiment A dissertation submitted in partial satisfaction of the requirements for the degree Doctor of Philosophy in Physics by Daniel Stuart Klein Committee in charge: Professor Frank Wurthwein,¨ Chair Professor Avraham Yagil, Co-Chair Professor Rommie Amaro Professor Pamela Cosman Professor Benjam´ın Grinstein 2018 Copyright Daniel Stuart Klein, 2018 All rights reserved. The dissertation of Daniel Stuart Klein is approved, and it is acceptable in quality and form for publication on microfilm and electronically: Co-Chair Chair University of California San Diego 2018 iii DEDICATION This dissertation is dedicated to the memory of my grandmother, Dr. Isabelle Rapin (1927-2017). To everyone else, a titan of pediatric neurology. To me, one of my staunchest supporters. iv EPIGRAPH Now you see why your father and I call it ’gradual school’. —Mom v TABLE OF CONTENTS Signature Page....................................... iii Dedication.......................................... iv Epigraph...........................................v Table of Contents...................................... vi List of Figures....................................... -
Advances in Theoretical & Computational Physics
ISSN: 2639-0108 Research Article Advances in Theoretical & Computational Physics Supreme Theory of Everything Ulaanbaatar Tarzad *Corresponding author Ulaanbaatar Tarzad, Department of Physics, School of Applied Sciences, Department of Physics, School of Applied Sciences, Mongolian Mongolian University of Science and Technology, Ulaanbaatar, Mongolia, University of Science and Technology E-mail: [email protected] Submitted: 27 Mar 2019; Accepted: 24 Apr 2019; Published: 06 June 2019 Abstract Not only universe, but everything has general characters as eternal, infinite, cyclic and wave-particle duality. Everything from elementary particles to celestial bodies, from electromagnetic wave to gravity is in eternal motions, which dissects only to circle. Since everything is described only by trigonometry. Without trigonometry and mathematical circle, the science cannot indicate all the beauty of harmonic universe. Other method may be very good, but it is not perfect. Some part is very nice, another part is problematic. General Theory of Relativity holds that gravity is geometric. Quantum Mechanics describes all particles by wave function of trigonometry. In this paper using trigonometry, particularly mathematics circle, a possible version of the unification of partial theories, evolution history and structure of expanding universe, and the parallel universes are shown. Keywords: HRD, Trigonometry, Projection of Circle, Singularity, The reality of universe describes by geometry, because of that not Celestial Body, Black Hole and Parallel Universes. only gravity is geometrical, but everything is it and nothing is linear. One of the important branches of geometry is trigonometry dealing Introduction with circle and triangle. For this reason, it is easier to describe nature Today scientists describe the universe in terms of two basic partial of universe by mathematics circle. -
Baryon and Lepton Number Anomalies in the Standard Model
Appendix A Baryon and Lepton Number Anomalies in the Standard Model A.1 Baryon Number Anomalies The introduction of a gauged baryon number leads to the inclusion of quantum anomalies in the theory, refer to Fig. 1.2. The anomalies, for the baryonic current, are given by the following, 2 For SU(3) U(1)B , ⎛ ⎞ 3 A (SU(3)2U(1) ) = Tr[λaλb B]=3 × ⎝ B − B ⎠ = 0. (A.1) 1 B 2 i i lef t right 2 For SU(2) U(1)B , 3 × 3 3 A (SU(2)2U(1) ) = Tr[τ aτ b B]= B = . (A.2) 2 B 2 Q 2 ( )2 ( ) For U 1 Y U 1 B , 3 A (U(1)2 U(1) ) = Tr[YYB]=3 × 3(2Y 2 B − Y 2 B − Y 2 B ) =− . (A.3) 3 Y B Q Q u u d d 2 ( )2 ( ) For U 1 BU 1 Y , A ( ( )2 ( ) ) = [ ]= × ( 2 − 2 − 2 ) = . 4 U 1 BU 1 Y Tr BBY 3 3 2BQYQ Bu Yu Bd Yd 0 (A.4) ( )3 For U 1 B , A ( ( )3 ) = [ ]= × ( 3 − 3 − 3) = . 5 U 1 B Tr BBB 3 3 2BQ Bu Bd 0 (A.5) © Springer International Publishing AG, part of Springer Nature 2018 133 N. D. Barrie, Cosmological Implications of Quantum Anomalies, Springer Theses, https://doi.org/10.1007/978-3-319-94715-0 134 Appendix A: Baryon and Lepton Number Anomalies in the Standard Model 2 Fig. A.1 1-Loop corrections to a SU(2) U(1)B , where the loop contains only left-handed quarks, ( )2 ( ) and b U 1 Y U 1 B where the loop contains only quarks For U(1)B , A6(U(1)B ) = Tr[B]=3 × 3(2BQ − Bu − Bd ) = 0, (A.6) where the factor of 3 × 3 is a result of there being three generations of quarks and three colours for each quark. -
Nobel Pris Og NBI
Hvilke forskere, både danske og udenlandske, med tilknytning til NBI har gennem tiden modtaget en nobelpris? M I Nobelpristagere med tilknytning til NBI Der er en lang række Nobelpristagere, som har været ansat i en eller anden form på NBI (Niels Bohr Institutet). Der er desuden en del, der har opholdt sig og arbejdet på institutet i en periode, men ikke har været ansat. De har så været lønnet af deres hjemmeuniversitet og brugt tiden til et samarbejde med en eller flere forskere på NBI, som oftest med en videnskabelig artikel som resultat. Endeligt har der i ”utallige” år været en skik, at fysik nobelpristagere blev inviteret til at komme til København, give en forelæsning, og efter eget ønske blive lidt tid umiddelbart efter modtagelsen af Nobelprisen (hvor de jo alligevel var i Stockholm). I den form har en meget stor del af nobelpristagerne efter institutets oprettelse, været på besøg.. Jeg husker selv fra et af mine første studieår en strålende forelæsning af: Donald Arthur Glaser f: 1926 i USA nobelpris i 1960, med en efterfølgende animeret fest med nobelpristageren i fysik- matematik- og kemi- studerendes forening (som hed parentesen). Der har især i Bohrs tid men været en lang række konferencer og møder, hvor stort set hele den videnskabelige verdens store, har været tilstede f.eks.: Max Karl Ernst Ludwig Planck f: D 1858 d: 1947 nobelpris 1916, Albert Einstein f: D 1879 d: 1955 nobelrpis 1921, Douglas D. Osheroff f: USA 1945 nobelpris 1996 og mange, mange andre. I den nedenstående liste er udvalgt de, der dokumenterbart har haft en eller anden form for regulær ansættelse på NBI.