Estimation of Cryogenic Heat Loads in Cryomodule due to Thermal Radiation
Cryogenic system is one of major cost drivers in high intensity superconducting (SC) continuous wave (CW) accelerators. Thermal radiations coming through the warm-ends of cryomodule and room temperature parts of the power coupler result in additional cryogenic heat loads. Excessive heat load in 2K environment may degrade overall performance of the cavity. In this paper we present studies performed to estimate additional heat load at 2K due to thermal radiation in 650 MHz cavity cryomodule in high energy section of PIP-II SC linac.
Design of a medium energy, high average power superconducting e-beam accelerator for environmental applications
We present the technical and engineering design of a medium energy (10 MeV) and high average power (1 MW) electron beam accelerator intended for irradiation treatment of high volume industrial and municipal wastewater. The accelerator uses superconducting radiofrequency (SRF) cavity technology for producing the high average beam power with >90% RF to beam efficiency. The design of the accelerator is simplified and tailored for industrial settings by adopting the cryocooler conduction-cooling technique for the SRF cavity instead of a conventional liquid helium bath cryo-system. The technical design is supplemented with a detailed analysis of capital and operating cost of the accelerator. The designed accelerator can treat up to 12 million gallons per day of wastewater, requires capital of ~$8M for construction, and has ~13.5 ¢/ton/kGy in material processing cost.
Development of High Power CW Klystrons for TRISTAN
At tile initial stage of operation of the TRISTAN MR, 16 high power klystrons are used to deliver an RF power over 0.8 MW per tube to accelerating cavities of an alternating periodic structure (APS) operating at 508.58 MHz. In close cooperation between KEK and tube industry, extremely high power klystrons (E3786) have been successfully developed after overcoming several technical difficulties. The highest RF output power of 1.25 LMW with efficiency above 66.7 percent and gain above 55 dB has been reached. Half of the RF power stations are being occupied with this type of tubes.