Prompt Radiation Dose Analysis Within the European Spallation Source Connection Cell

Abstract

The European Spallation Source (ESS) is a pulsed spallation neutron source currently being built in Lund, Sweden. At full power and beam energy, ESS will accelerate protons to 2 GeV at 5 MW (average pulse current of 62.5 mA, pulse length of 2.86 ms, and repetition rate of 14 Hz) onto a rotating, helium-cooled, tungsten target. This target is in a heavily shielded structure referred to as the target monolith, which is located inside the ESS target building. Directly on top of the target monolith shielding is a room referred to as the connection cell, which contains many important utility connections and control systems. Many connections from components in the target monolith, e.g., cooling water and electrical connections, exit the monolith into the connection cell and pass through the walls of the connection cell to reach other areas of ESS. When the accelerator is operating at ESS, the connection cell will be off limits to humans. This paper evaluates the prompt dose rates to several important materials in the connection cell and suggests an algorithm for evaluating the suitability of materials that might be used in the connection cell.

Keywords:

• Spallation
• target monolith
• material dose

Acknowledgments

Several other ESS employees and in-kind partners should be acknowledged for their contributions to this work. Y. Lee, M. Ferrari (University of Brescia), and K. Sjögreen provided input data for the connection cell materials evaluated in this work. O. Gonzalez (ESS Bilbao), E. Klinkby (Technical University of Denmark), and A. Takibayev provided input regarding the MCNP model.

Disclosure Statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the European Spallation Source.