{'fraction_non_alphanumeric': 0.0152, 'fraction_numerical': 0.0032, 'mean_word_length': 4.660633484162896, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
The neutralization of space charge in the planar diode: I. By the injection of positive ions

The space charge produced by cathode electron emission is neutralized by the injection of ions normal to the cathode surface. This treatment is primarily intended for application to field emission diodes, and therefore the field at the cathode surface is of considerable importance. The electron current and cathode field are evaluated as a function of ion current and ion injection energy. As a special case these results are applied to the generation of an intense ion beam by anode field emission. It is shown that the field at the anode surface is increased by the presence of simultaneous electron flow and has a maximum value equal to fraction four-thirds of the space-charge-free field. Generally an increase in the ion current leads to an increase in the cathode field for given values of electron current and ion injection energy. However, for prescribed values of the cathode field and ion current, it is found that the electron current has a broad maximum when expressed as a function of ion injection energy. Over the range of parameters studied the optimum value of ion injection energy lies between 40% and 70% of the inter-electrode voltage.