Physics and Astronomy Colloquium"The highest energy photons: using ultra-peripheral collisions at the LHC and RHIC to probe nuclear structure and test the standard model" - Dr. Spencer Klein, Lawrence Berkeley National Laboratory
This event is in the past.
Abstract: High-energy photons are a simple tool with many uses. The most
energetic photons today are those that are produced in ultra-peripheral
collisions (UPCs) involving protons or heavier ions. The
relativistically boosted electromagnetic fields of these ions act like a
flux of nearly-real photons. To the target (other) nucleus, the
energies reach the PeV (10^15 eV) range. I will discuss a number of
physics topics that are being studied using these photons, including
photon-photon scattering, production of antihydrogen atoms, and using
these photons to probe nuclear structure, particularly via vector meson
photoproduction. Photoproduction is sensitive to the density and
spatial distribution of gluons with very low momentum (Bjorken-x).
Finally, I will conclude with a brief look forward to the recently
approved ("CD-0" in Dept. of Energy parlance) electron-ion collider.