1 / 37

Introduction

Introduction. November 2002. Good News. House. Senate. References. All of the above can be downloaded from our website Go to “Documents” - top of left frame:. Periodic Table. n. n. p. p. Spectroscopy of the Atom. Discovery of the Hadrons.

velma
Download Presentation

Introduction

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Introduction

  2. November 2002

  3. Good News

  4. House Senate

  5. References All of the above can be downloaded from our website Go to “Documents” - top of left frame:

  6. Periodic Table n n p p

  7. Spectroscopy of the Atom

  8. Discovery of the Hadrons In the 50’s and 60’s physicists discovered over 100 elementary particles incosmic ray showers and accelerators. Almost all of these were short-livedand were classified as mesons or baryons. Bubble chamber photo Typical lifetime:10-23 s Baryons have half-integer spin and obey Pauli Exclusion Principle (PEP). They are fermions. Mesons have integer spin and do not obey the PEP. They are bosons.

  9. Discovery of Elementary Particles in showers of Cosmic Rays

  10. Spectroscopy of Hadrons proton neutron π meson Baryons Mesons

  11. Standard Model Electromagnetic force explains atoms Ordinary Matter Strong Force binds quarks Electroweak force explains radioactivity

  12. Subatomic Sizes

  13. Color

  14. No Free Quarks Color Field: Because of self interaction, confining flux tubes form between static color charges

  15. Lattice Calculations and Flux Tubes From G. Bali: quenched QCD with heavy quarks

  16. Flux Tube Breaking

  17. Exciting the Flux Tube There are two degenerate first-excited transverse modes with J=1– clockwise and counter-clockwise – and their linear combinations lead toJPC = 1– + or JPC=1+ – for the excited flux-tube Normal meson:flux tube in ground state Excitedfluxtube

  18. The Light Quarks and Light Mesons JPC = 0– +0++1– – 1+ –2++ … Allowed combinations JPC = 0– –0+ –1– +2+ – … Not-allowed: exotic Expect to find nine mesons with the same J, P, C - a nonet

  19. Quantum Numbers for Hybrid Mesons Exotic Excited Flux Tube Quarks Hybrid Meson like like So only parallel quark spins lead to exotic JPC

  20. QCD and Spectroscopy

  21. Exotic Hybrids Will Be Found More Easily in Photoproduction There are strong indications from theory that photons will produceexotic hybrid mesons with relatively large cross sections. Production of exotichybrids favored.Almost no data available Quark spins already aligned

  22. Coherent Bremsstrahlung Incoherent & coherent spectrum 40% polarization in peak collimated tagged with 0.1% resolution 12 GeV electrons flux This technique provides requisite energy, flux and polarization Linearly polarized photons out electrons in spectrometer diamond crystal photon energy (GeV)

  23. Tagger Magnet

  24. Aerial View of Jefferson Lab

  25. Linac

  26. Cryomodule

  27. Arcs

  28. Helium Factory

  29. UpgradePlan

  30. Detector

  31. Lead GlassCalorimeter &Magnet Magnet arrives in Bloomington

  32. Electronics PMT Bases: FADCs: Electronics assemblyrobotics facility to be installed at IU in June

  33. TOF Prototype $70K from JLab

  34. Magnetic Shielding Helmholtz coils built by undergrads lastyear - upgraded this year new power supplies

  35. Collaboration History • Founded in 1998 • Workshops (latest in May 2003) • 4th Design Report • Collaboration meetings • Regular conference calls • Management plan • Collaboration Board Reviews • PAC12 • Cassel Review • APS/DNP Town Meeting • NSAC LRP • PAC23

  36. Computational Challenge • GlueX will collect data at 100 MB/sec or 1 Petabyte/year - comparable to LHC-type experiments. • Close collaboration with computer scientists has started and the collaboration is gaining experience with processor farms.

  37. Conclusions The spectroscopy of light quark mesons is on the verge of makingimportant contributions to answering a fundamental question: What is the nature of confinement in QCD? We welcome additional collaborators - theory and experimentand bright, enthusiastic undergrads

More Related