Nuclear Physics UConn Mentor Connection Mariel Tader UConn

Nuclear Physics UConn Mentor Connection Mariel Tader UConn Mentor Connection 2010, Mari Tader

The Standard Model Describes three of the four “fundamental” forces • Electromagnetism, weak and strong interactions • There are 12 different kinds of elementary particles UConn Mentor Connection 2010, Mari Tader 2

The Forces • Electromagnetism: why opposites attract • Biology/ Chemistry • Strong Force: holds quarks together • Weak Force: mediates fundamental particle decay • (Gravity): not included in Standard Model UConn Mentor Connection 2010, Mari Tader 3

Electroweak Theory • Electromagnetism and weak force are two different aspects of the same force: electroweak • The two merge into the same force at high energies and close distance UConn Mentor Connection 2010, Mari Tader 4

The particles • 6 Quarks: make up protons, neutrons, etc. • 6 Leptons: electrons, neutrinos, etc. • Force carriers: gluons for strong force, etc. • Weak force’s range • The three generations UConn Mentor Connection 2010, Mari Tader 5

Antimatter • Each type of particle has a comparable anti-particle • The same properties, except charge • The mystery: why so much more matter? • Annihilation: matter and antimatter collide a Z boson/gluon/photon form decay into new matter/ antimatter pair UConn Mentor Connection 2010, Mari Tader 6

The Nucleus • Quarks: come in threes (protons/ neutrons/ etc. ) or twos (mesons) • Gluons: hold quarks together, force carrier particle for strong force UConn Mentor Connection 2010, Mari Tader 7

Quantum Numbers • Electric Charge: all particles except quarks have integer charge, quark charges add to whole numbers • Flavor: different kinds of quarks/ leptons • Spin: goes by 1/2 s, particles/ nuclei • Lepton/baryon numbers, etc. • Color Charge: gets its own slide • Angular momentum/ momentum: location • Weak Charge: strength of weak force UConn Mentor Connection 2010, Mari Tader 8

Color Charge • Why quarks come in threes or twos: neutral charge • Why quarks stay together: color force field • Quark: 1 of 3 colors • Anti-quark: 1 of 3 anti-colors • Gluon color charges: 1 color and 1 anti-color combination UConn Mentor Connection 2010, Mari Tader 9

Bosons and Fermions • Pauli Exclusion Principle: “two particles can’t have identical sets of quantum numbers” • Fermions: obey Pauli • Bosons: violate Pauli UConn Mentor Connection 2010, Mari Tader 10

Radiation • Unstable nuclei decay • Alpha: release of 2 protons/2 neutrons (helium nucleus) • Beta: release of an electron • Gamma: release of photons (as gamma rays) • Neutron radiation: like it sounds UConn Mentor Connection 2010, Mari Tader 11

Fundamental Particle Decay • Unlike atoms, fundamentals can not break into constituents • To become a less massive particle: 1. Emit a force carrier (W boson) “virtual” 2. W boson immediately decays into lighter particles UConn Mentor Connection 2010, Mari Tader 12

Virtual Particles • Can not be detected directly • Can break “conservation of energy” for a very short time You can not see virtual particles, but you can see the before and after UConn Mentor Connection 2010, Mari Tader 13

The Project • Thomas Jefferson National Accelerator • The collaboration • Will be the first to observe and study exotic mesons • Will begin 2014 UConn Mentor Connection 2010, Mari Tader 14

gluex • Glue. X hopes to learn about quarks, gluons, and confinement by creating exotic mesons • How we “see” the gluons: Polarized beam liquid hydrogen target exotic mesons final particles and radiation data deciphered UConn Mentor Connection 2010, Mari Tader 15

Bremsstrahlung • German for “braking radiation” • A radiation particle interacts with atoms and creates more radiation, while losing the corresponding energy Atom UConn Mentor Connection 2010, Mari Tader 16

Coherent Bremsstrahlung • Must be in a crystal • Particle/crystal must be in correct alignment • A few specific wavelengths are prevalent, “peaks” UConn Mentor Connection 2010, Mari Tader 17

Reciprocal Lattice Vectors • Bravais Lattice: repeating crystalline arrangements of points • Reciprocal Lattice: made from the vectors perpendicular to three of the vectors of the original • Used as a simple geometric model that can interpret diffraction in crystals UConn Mentor Connection 2010, Mari Tader 18

Framing the Crystal • A frame would produce too much unwanted bremms. diamond is mounted on tiny carbon fibers • The resonant frequency of the fibers should be known, to minimize rotation UConn Mentor Connection 2010, Mari Tader 19

Vibration • Interference: two or more superimposed waves create a new wave pattern: need coherent bremss. • Resonant frequency: An objects natural frequency of vibration • Gluonic flux tube vibration is like a string UConn Mentor Connection 2010, Mari Tader 20

The Carbon Wire • The theoretical model vs. the experimental data • How we modeled it • The glue ball equation • How we measured it • Uncertainty bars UConn Mentor Connection 2010, Mari Tader 21

Polarization • The orientation of the wave’s electric/ magnetic fields • Transverse wave: polarization is perpendicular to wave’s direction • Linear Polarization: the electric or magnetic field is oriented in one direction, i. e. no rotation (chirality) UConn Mentor Connection 2010, Mari Tader 22

Putting it all together • The process: Electron beam diamond wafer polarized photons hit mesons detectors UConn Mentor Connection 2010, Mari Tader 23