Revealing the origins of vortex cavitation in a Venturi tube by high speed X-ray imaging by Soyama, H, Liang, X, Yashiro, W, Kajiwara, K, Asimakopoulou, E, Bellucci, V, Birnsteinova, S, Giovanetti, G, Kim, C, Kirkwood, HJ, Koliyadu, JCP, Letrun, R, Zhang, Y, Ulicny, J, Bean, R, Mancuso, A, Villanueva-Perez, P, Sato, T, Vagovic, P, Eakins, D, Korsunsky, A