Observation of double pseudowaves in an ion–beam–plasma system Project supported by the National Natural Science Foundation of China (Grant Nos. 11575183 and 11705201). |
(color online) (a) The dependence of the signals received at 140 mm from the excitation grid with respect to τ when Vpp = 12 V, VSG2 = −40 V, and εb = 3.2 eV. (b) The peak value of the signals versus τ. |