“Probe Peta-Tesla Magnetic Field in QGP with Dielectrons from Photon-Photon Collisions”
We presents first measurements of $e^+e^-$ pair production from light-light scattering in non-central high-energy heavy ion collisions. The excess yields peak distinctly at low transverse momentum between 40 to 60 MeV/c. The excess yields can be explained only when the photon-photon interactions are included in model calculations. However, the measured $p_T$ distributions are significantly broader than model calculation and are different between Au+Au and U+U collisions. Our measurements provide a possible experimental evidence of the existence of strong magnetic field at peta-Tesla scale. And I will discuss its possible impact on emerging phenomena in hadronic heavy-ion collisions.