Dissipation of electron-beam-driven plasma wakes.

Metre-scale plasma wakefield accelerators have imparted energy gain approaching 10 gigaelectronvolts to single nano-Coulomb electron bunches. To reach useful average currents, however, the enormous energy density that the driver deposits into the wake must be removed efficiently between shots. Yet mechanisms by which wakes dissipate their energy into surrounding plasma remain poorly understood.

Subthreshold changes in excitable membranes of Cucurbits pepo L. stem cells during cooling-induced action-potential generation.

The nature of subthreshold changes in excitable plasma membranes has been investigated in stem parenchyma cells of Cucurbita pepo L. during action-potential generation induced by gradual cooling (from 23 to 10 ° C). The character of the subthreshold depolarization of excitable cells is shown to be mainly defined by a decrease in the activity of the plasma-membrane electrogenie pump (H(+)-ATPase).