We study the transport dynamics of momenta deposited from jets in ultrarelativistic heavyion collisions. Assuming that the high-energy partons traverse expanding quark-gluon fluids and are subject to lose their energy and momentum, we simulate dijet asymmetric events by solving relativistic hydrodynamic equations numerically without linearization in the fully (3+1)-dimensional coordinate. Mach cones are formed and strongly broadened by radial flow of the background medium. As a result, the yield of low-pT particles increases at large angles from the jet axis and compensates the dijet momentum imbalance inside the jet-cone. This provides an intimate link between the medium excitation by jets and results in dijet asymmetric events observed by the CMS Collaboration. Introduction.-The quark gluon plasma (QGP), supposed to have filled the early universe a few microseconds after the Big Bang, is the deconfined state of quarks and gluons realized under an extremely hot and dense condition [1]. In heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC) at BNL and the Large Hadron Collider (LHC) at CERN, the QGP is created experimentally. By colliding relativistically accelerated heavy nuclei, extremely high-temperature is achieved in the experiments. From the analysis of experimental data of elliptic flow, it has turned out that the QGP behaves like an almost-perfect fluid because of the strong interacton among the constituent particles [2-6].Jets, namely partons with large transverse momenta, are created in hadron or nuclear collisions at collider energies. In nuclear collisions, these partons are subject to traverse a hot and dense medium. While traversing the medium, the parton loses its energy through strong interaction between them [7][8][9][10][11][12][13]. Through the amount of lost energy, one can extract one of the fundamental properties of the medium, namely stopping power of the QGP against high-energy partons. In addition, the energymomentum deposition from jets excites the medium and propagation of this medium excitation may give information about the transport coefficients and the sound velocity of the QGP. Thus jet quenching phenomena provide a unique opportunity to probe the properties of the primordial matter composed of elementary particles in quantum chromodynamics (QCD).The next question is where and how this lost energy diffuses inside the medium. In experiments, a large number of low-p T hadrons at large angles from an axis of the quenched jet is observed in Pb-Pb collisions at the LHC [14]. The total transverse momentum of these low-p T particles together with the quenched jet balances that of