Rabbit Anti-Human SRF (Phospho-Thr159) polyclonal antibody

Purpose Niobium sputtered on copper has been a popular alternative approach for superconducting radio frequency (SRF) community in the last few decades. Comparing to bulk materials of a few millimeters, high-purity niobium of merely a few microns is sufficient to realize superconductivity on the coated surface. Being niobium thin film, it has been widely acknowledged that surface quality of the substrate plays a vital role in obtaining a superior niobium coating with excellent SRF performance. Therefore, proper chemical treatment of the substrate before coating is crucial and the ultimate goal is to create a smooth and defect-free surface. Prior to the design of a cavity etching system, the mechanism of SUBU as well as two industry-used solutions is studied in detail on samples. Methods Copper samples were first pre-treated by mechanical grinding to remove fabrication damages, obvious defects and visible impurities. Two chemical solutions widely used in industries were subsequently chosen to etch the samples. Finally, the established SUBU solution was used independently on these pre-treated samples for comparison. Surface morphology and etching rate were measured accordingly. Results and conclusions Mirror-like copper surface was created by using the SUBU solution thus qualified for subsequent niobium sputtering, while the other two solutions used in industries were less effective with nonideal surface morphology. The chemical reactions, the experimental requisites and the involved processes are extensively elucidated for all three solutions. Limitations for SUBU were examined, and the optimum ratio of the chemical bath volume to sample surface area was also determined. These investigations will serve as an important guidance for the development of a chemical etching system for elliptical copper cavities.

There exists a need for reliable, high-power electron sources for applications including those in discovery science, security, medical and industrial engineering. Today, there are many examples of high-average-power electron sources, but they are not, for instance, simultaneously compact, highly efficient, and available at a reasonable cost. Exploiting recent advances in superconducting, radio-frequency (SRF) cavities and RF power sources as well as innovative solutions for the SRF gun and cathode system, we have developed a design concept for a truly compact, SRF, high-average power electron linac source integrating a thermionic cathode system. Potentially capable of 50 kW average power and continuous-wave operation, this accelerator design will produce electron beams with energies up to 10 MeV. In this paper, we present in detail the electromagnetic design results of our 9-cell accelerating structure with its integrated, thermionic cathode structure.