title: Development of multi-pixel x-ray source using oxide-coated cathodes.
abstract: Multiple pixel x-ray sources facilitate new designs of imaging modalities that may result in faster imaging speed, improved image quality, and more compact geometry. We are developing a high-brightness multiple-pixel thermionic emission x-ray (MPTEX) source based on oxide-coated cathodes. Oxide cathodes have high emission efficiency and, thereby, produce high emission current density at low temperature when compared to traditional tungsten filaments. Indirectly heated micro-rectangular oxide cathodes were developed using carbonates, which were converted to semiconductor oxides of barium, strontium, and calcium after activation. Each cathode produces a focal spot on an elongated fixed anode. The x-ray beam ON and OFF control is performed by source-switching electronics, which supplies bias voltage to the cathode emitters. In this paper, we report the initial performance of the oxide-coated cathodes and the MPTEX source.
authors.affiliation: Department of Radiation Oncology, Washington University in St. Louis School of Medicine, St. Louis, MO, United States of America.
authors.forename: Praneeth
authors.initials: P
authors.lastname: Kandlakunta
authors.forename: Richard
authors.initials: R
authors.lastname: Pham
authors.forename: Rao
authors.initials: R
authors.lastname: Khan
authors.forename: Tiezhi
authors.initials: T
authors.lastname: Zhang
mesh_terms: D004566:Electrodes; D004867:Equipment Design; D010087:Oxides; D012666:Semiconductors; D014057:Tomography, X-Ray Computed / Q000295:instrumentation*
chemical_list: D010087:Oxides