Observation of the polarization electric field in the intense neutralized proton beam propagating undeflectedly across a magnetic field

金沢大学理工研究域数物科学系A neutralized proton beam (averaged velocity v=3.6×108 cm/s, velocity spread v=0.9×108 cm/s, proton current density 18 A/cm2) is injected into a transverse magnetic field B(3 kG). It is found that the electric field which satisfies the condition E=vB value is formed in the beam and the beam propagates across the magnetic field by the polarization drift when the dielectric constant =1+(pici)2 of the beam is larger than 100-180. The lowest value of for the beam propagation given above is consistent with the theoretical prediction 43. © 1982 The American Physical Society