Measurement of scaling laws for shock waves in thermal nonlocal media
  We are able to detect the details of spatial optical collisionless wave-breaking through the high aperture imaging of a beam suffering shock in a fluorescent nonlinear nonlocal thermal medium. This allows us to directly measure how nonlocality and nonlinearity affect the point of shock formation and compare results with numerical simulations. 
N. Ghofraniha, L. Santamaria Amato, V. Folli, S. Trillo, E. DelRe and   C. Conti
physics.optics