Schedule for Physics 724 - Fall 2005

PHYS 724 Home Page

Date Reading and Homework Assignment
Thu. Aug. 18, 2005 Optional Homework due today!
Homework (Due on Monday, Aug. 29, 2005):
  1. Work out the e- mu- -> e- mu- process yourself, from start to finish, in detail.
  2. Work out the e- mu- -> e- mu- process in the lab frame (section 6.8). Once again, work this all out by yourself, in detail, i.e., derive eq. 6.50 from scratch.
  3. Do exercise 6.8, i.e, derive eq. 6.51 from scratch.
The goal here is to make sure you can do gamma matrix algebra on your own and use it to solve problems. If you can do this, you have mastered the essentials of working out Feynman diagrams! Do NOT wait until the last minute to do this homework, it may be quite demanding. Do problem 1 now and problems 2 and 3 on Tuesday and Thursday of the week starting 8/22. Send me e-mail if you have any trouble.
Tue. Aug. 30, 2005 Lecture:
  1. Convert uniform distribution in c.m. frame to lab frame.
  2. Justify the tensor for a spinless particle using symmetry arguments.
  3. Compute total e+e- -> mu+mu- cross-section, angular distribution.
No homework assigned.
Thu. Sep. 1, 2005 Lecture:
  1. "Left" and "Right" handed components of spinors.
  2. Discussion of total and differential cross-sections for e+e- -> mu+mu-.
  3. Photon Polarization Vectors: why there are only 2 independent ones.
Homework: Problems 6.4, 6.5. Due on Fri. 9/9/05.
Fri. Sep. 2, 2005 Lecture:
  1. Photon polarization vectors: explicit forms, normalization, and completeness relation.
  2. Massive vector boson polarization vectors: there are three of these, their explicit forms and their completeness relation.
  3. Propagators for spin-0, spin-1/2 and spin-1 particles.
  4. A calculation of the matrix-element squared for Compton Scattering.
Homework: Problems 6.19, 6.20. Due on Fri. 9/9/05.
Tue. Sep. 6, 2005 Lecture:
  1. Derive the general form for the inelastic electron-proton scattering cross-section.
  2. Discuss the simplifications observed in data:
    • Reduction to a single function, say W1(x, Q2)
    • Dependence on a single variable x at high Q2
  3. Significance of this reduction deduced by comparing to e-μ scattering cross-section
Homework: 8.15. Due on Thu. 9/15/05.
Thu. Sep. 8, 2005 Lecture:
  1. We derived the main expression of the parton model, eq. (9.19 + 9.20)/2
  2. We began to identify the various components of the proton (valence, sea quark distributions).
Homework: Exercise 9.4. Due on Thu. 9/15/05.
Fri. Sep. 9, 2005 Lecture:
  1. Solution of Ex. 6.19.
  2. Parton Distribution Functions: valence and sea quarks.
  3. Behaviour of pdfs as x → 0 and x → 1.
  4. Ratio of F2 in en and ep scattering.
  5. Momentum and number sum rules.
  6. Explanation of R=0 in the parton model.
Homework: Exercise 9.5. Due on Thu. 9/15/05.
Tue. Sep. 13, 2005 Lecture:
  1. Introduction: Scaling violations and the Altarelli-Parisi equations.
  2. QED → QCD: transforming to the γ*q → qg cross-section.
  3. Calculation of the splitting function Pqq(z).
Homework: Exercise 10.5. Due on Thu. 9/22/05.
Thu. Sep. 15, 2005 Lecture:
  1. Discussion of an ep scattering "research" project.
  2. Discussion of other projects.
Homework: Suggest at least one project topic to me by e-mail. In detail! Due on Mon. 9/19/05.
Tue. Sep. 20, 2005 Lecture:
  1. Discussion of project presentations and reports.
  2. The Drell-Yan cross-section in the parton model.
  3. Quark fragmentation functions.
  4. Multiplicity as a function of energy.
Homework: Exercises 11.2, 11.4. Due on Thu. 9/29/05.
Thu. Sep. 22, 2005 Lecture:
  1. 3-jet events: kinematics.
  2. Differential cross-section.
  3. Running coupling constants, the perturbative and non-perturbative regions in QCD, and leading-log results.
  4. Modification of the parton model expressions for Re+e- and the GLS sum-rule.
Homework: Exercise 11.5. Due on Thu. 9/29/05.
Tue. Sep. 27, 2005 Lecture:
  1. A historical introduction to Weak Interactions.
  2. Lessons from Beta Decay: Existence and Spin of the Neutrino.
  3. The Fermi theory of weak interactions and what's wrong with it.
  4. The V-A theory. History. V-A plus vector bosons.
  5. What we can learn from pion decay.
Homework: Do the first homework in this table (see Aug. 18 - it's listed as "Optional" there).
Due on Thu. 10/6/05.
Thu. Sep. 29, 2005 Lecture: To be held later.
Homework: Explain, in the non-relativistic limit, whether the axial vector current allows for
nucleon spin-flip transitions, no-flip transitions or both.
Due on Thu. 10/6/05.
Tue. Oct. 4, 2005 Lecture:
  1. What ails the Fermi theory: partial wave cross-sections ~ 1/s,
    while e-ν cross-section ~ s.
  2. K0L → μ μ and the GIM mechanism: prediction and discovery of charm.
  3. Classification: Leptonic, Semileptonic and Nonleptonic weak decays.
  4. Electron-neutrino scattering via W bosons: differential and total cross-sections.
Homework: Due on Tue. 10/18/05.
Thu. Oct. 6, 2005 Lecture:
  1. Beta Decay, Generalities: Allowed, Superallowed decays, form factors, V-A form, Fermi and Gamow-Teller decays.
  2. Polarization of electrons emitted.
  3. Decay rate based on dimensions of 1/t.
Homework: 12.1, 12.3, 12.4.
Due on Tue. 10/18/05.
Tue. Oct. 11, 2005 Lecture:
  1. Nuclear Beta Decay: matrix element squared, differential and total cross-sections.
    Comparison with muon decay: the cosine of the Cabibbo angle.
  2. Nuclear Beta Decay: discussion of Kurie plot, end-point of electron energy spectrum.
  3. Muon Decay: Total decay rate.
  4. Pion Decay: Using the Dirac equation to simplify the matrix element.
  5. Pion Decay: Helicity suppression: Γ ∝ m2l.
Homework: Work out the differential and total muon decay rate in detail, i.e., all of section 12.5 up to eq. (12.42) including exercises 12.8, 12.9 and 12.10.
Due on Thu. 10/20/05.
Tue. Oct. 18, 2005 Lecture:
  1. Oct. 24 is the deadline for a first draft of the presentation.
  2. Oct. 31 is the deadline for a first draft of the report.
  3. Oct. 31 is the deadline for the final draft of the presentation.
  4. The muon decay spectrum and the Michel parameter ρ.
  5. Charged Current (CC) Neutrino-nucleon scattering: total and differential cross-sections obtained using the parton model.
  6. Weak Neutral Current (NC) couplings.
Homework:
  1. A baseball player takes a swing at a tightly focused neutrino beam. Each neutrino in the beam has an energy of 100 GeV. Assume only charged-current interactions occur. Estimate the number of neutrinos needed in the beam for the player to feel the same force as when he strikes a regular baseball in a major-league game. Assume a head-on collision between the tip of the bat (say over an area of ~25 cm2) and the beam; assume also that the neutrinos are tightly bunched in time: the beam is uniformly spread within a millisecond. Is it safe to be the catcher?
  2. Halzen and Martin Exercise 12.18.

Due on Tue. 10/25/05.
Thu. Oct. 20, 2005 Lecture:
  1. Ratios of sums and differences of the NC ν and ν-bar cross-sections to corresponding ones for CC: Paschos-Wolfenstein ratios.
  2. W, Z production and decay.
  3. W cross-sections, W spin.
  4. Electroweak asymmetries.
Homework: Exercises 13.3, 13.4, 13.5, 13.6.
Due on Tue. 10/25/05.
Tue. Oct. 25, 2005 Lecture:
  1. Symmetries in Field Theories.
  2. Global and local symmetries.
  3. Noether's theorem and conserved currents.
  4. Spacetime and internal symmetries.
  5. Gauging the Dirac field: covariant derivatives.
Homework: Exercises 14.5, 14.6.
Due on Tue. 11/1/05.
Thu. Oct. 27, 2005 Lecture:
  1. History of Yang-Mills theories.
  2. Gauging Isospin: the SU(2) theory of Yang and Mills.
  3. Gauge transformation of the covariant derivative, the gauge fields and the field strength tensor.
  4. QCD: a color SU(3) theory.
  5. QED and QCD: a side-by-side comparison.
  6. Feynman diagrams in QCD.
Homework: Due on Tue. 11/1/05.
Tue. Nov. 1, 2005 Lecture:
  1. Spontaneous symmetry breaking: Goldstone bosons
  2. SSB with gauge fields: generating mass for a U(1) gauge boson
  3. Generating mass for SU(2) gauge bosons
  4. SU(2) x U(1): masses for the W, Z and photon
Homework: Work out the decay rate for the Z to nu-nubar and for the W to e-nu from the Feynman rules.
Due on Tue. 11/8/05.
Thu. Nov. 3, 2005 Lecture:
  1. The nu and e couplings to W and Z bosons and to photons.
  2. The Higgs Search at ALEPH (a presentation by Ryan White).
Homework: None.
Fri. Sep. 2, 2005 Lecture:
  1. The Full Standard Model Lagrangian: Gauge and Lorentz Invariant
  2. Fermion masses, the Higgs mass and Higgs couplings
  3. History of the Standard Model
  4. A Search for the Higgs at D0 (a presentation by Mike Paolone).
Homework: Starting from the Standard Model Lagrangian (eq. 15.40), work out the neutral current couplings, i.e., the last two columns of table 13.2.
Due on Tue. 11/15/05.
Tue. Nov. 8, 2005 Lecture:
  1. Mass matrices for quarks: diagonalization of mass terms in the SM Lagrangian.
  2. The KM matrix and why it must be complex.
  3. Discovery of the Top Quark at CDF (a presentation by Nathan Baltzell).
Homework: None.
Thu. Nov. 10, 2005 Lecture:
  1. The KM matrix
  2. CP violation in the SM
  3. Number of parameters in the SM
  4. Majorana mass terms
  5. Charge-conjugate wavefunctions
  6. Majorana neutrinos
  7. The MSW effect
  8. Discovery of a new Charm Baryon at SELEX (a presentation by Erdogan Ozel).
Homework: Derive eq. 5.40 from 5.39 and earlier definitions of C and ψc.
Due on Tue. 11/15/05.
Tue. Nov. 15, 2005 Lecture:
  1. History of neutrinos and neutrino oscillations.
  2. Significant neutrino oscillation experiments: Homestake, Kamiokande, Super-K, K2K.
  3. The seesaw mechanism and Majorana neutrinos.
  4. Future neutrino oscillation experiments.
  5. CP violation in neutrino oscillations, Leptogenesis.
  6. Solar Neutrinos and the SNO experiment (a presentation by Zhiwen Zhao).
Homework
Due on Tue. 11/22/05.
Thu. Nov. 17, 2005 Lecture:
  1. Heavy Quarks
  2. Spin Structure Functions (a presentation by Haiyun Lu).
Homework
Due on Tue. 11/22/05.
Tue. Nov. 22, 2005 Lecture:
  1. Grand Unified Theories, Supersymmetry and String Theory
  2. Renormalization, QED and the Lamb Shift (a presentation by Vladimir Montealegre).
Homework: None.
Tue. Nov. 29, 2005 Lecture:
  1. Physics beyond the Standard Model.
  2. Tracking at the LHC.
  3. B physics at the LHC.
No Homework.
Thu. Dec. 1, 2005 Lecture:
  1. Charm Physics, CLEO-c: Ian Shipsey.
  2. Will it be like this talk?
No Homework.

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