Murray Moinester's 80th Birthday Lecture
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From: Michael Cordonsky <mcordi@tauex.tau.ac.il> Date: Tue, Feb 11, 2020 at 5:02 PM Subject: [NHPI] Prof. Murray Moinester 80th Birthday, next Joint seminar, TUESDAY, 3 March, 2020 To: <NUCLEAR-HADRON-PHYSICS-IL@listserv.tau.ac.il> Dear Dear Nuclear/Hadron colleagues, We inform you that the next Nuclear Physics Joint Seminar is dedicated to the 80th birthday of Professor Murray Moinester, and will take place on Tuesday, March 3, 2020 in the Check Point building, ground floor, Hall 002, on the campus of Tel Aviv University. For more information on entrance/parking please contact Riki by phone 03-6408192 or e-mail: riki@post.tau.ac.il. A POSTER OF THE EVENT IS ATTACHED. Sincerely, Eli Piasetzky, Guy Ron, Alexander Milov, and Zvi Citron THE PROGRAM: ------------------------------------------- 14:30 - 14:45 Refreshments 14:45 - 15:45 "Pion Polarizability Status Report" Murray Moinester Tel Aviv University Abstract: Polarizabilities are well known as associated with the Rayleigh scattering cross section of sunlight photons on atomic electrons in atmospheric N2 and O2. The oscillating electric field of sunlight photons forces the atomic electrons to vibrate. Since the radiated power associated with their changing electric dipole moments depends on λ-4, the intensity of scattered and transmitted sunlight is dominated by blue and red, respectively. Similarly, the electric απ and magnetic βπ charged and neutral pion polarizabilities characterize the induced dipole moments of the pion during γπ Compton scattering via the interaction of the γ’s electromagnetic field with the quark substructure of the pion. In particular, απ is the proportionality constant between the γ’s electric field and the electric dipole moment, while βπ is similarly related to the γ’s magnetic field and the induced magnetic dipole moment. Pion polarizabilities affect the shape of the γπ Compton scattering angular distribution. By crossing symmetry, the γπ→γπ amplitudes are related to the γγ→ππ amplitudes. The polarizabilities are basic characteristics of the pion, and are therefore of fundamental interest in the low-energy sector of quantum chromodynamics. A stringent test of chiral perturbation theory (ChPT) is possible based on comparisons of precision experimental pion polarizabilities with ChPT predictions. The combination (απ-βπ) has been measured by: (1) radiative pion Primakoff scattering (Bremsstrahlung of 190 GeV/c negative pions) in the nuclear Coulomb field of the Ni nucleus: π- Ni → π- Ni γ, (2) two-photon fusion production of pion pairs γγ→ππ via the e+e− → e+e−π+π− reaction at SLAC Mark-II, (3) radiative pion photoproduction from the proton γp→ γπn at MAMI in Mainz. Only the CERN COMPASS charged pion polarizability measurement has acceptably small uncertainties. The COMPASS polarizabilities are in good agreement with ChPT predictions; and by Dispersion Relations with DESY Crystal Ball γγ → π0π0 data; strengthening the identification of the pion with the Goldstone boson of chiral symmetry breaking in QCD. This status report follows the 2019 IJMPA review by Moinester and Scherer at https://arxiv.org/pdf/1905.05640.pdf Links to the relevant polarizability articles are conveniently available at https://murraymoinester.com 15:45 - 16:15 Coffee Break 16:15 - 17:15 "Isotopic Techniques in Geophysics: Applications to Carbon Sequestration, Climate Chronometers, and Health Physics" Joel Kronfeld Tel Aviv University