English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

NOBORU, one of 23 instruments in the Materials and Life science experimental Facility (MLF) of Japan Proton Accelerator Research Complex (J-PARC), has been designed to evaluate characteristics of Japan Spallation Neutron Source (JSNS) and also used for a variety of applications. A heavy shielding structure was required for NOBORU to accept neutrons in very wide energy range up to 1 GeV with a large neutron beam cross section of 10 x 10 cm 2 at 1 MW. Neutronics calculations were fully applied to examine the shielding structure. In the shielding calculation, we considered various loss points of the neutron beam caused by several experimental setups. As a result, a shielding structure satisfied the radiation dose limits adopted at J-PARC for all the loss point conditions. Effectiveness of the neutron beam shutter was evaluated for radiation safety point of view. In addition, we evaluated radioactivity of a T0 chopper, which needs a periodic hands-on maintenance, for the radiation safety. To confirm the shielding calculation, we have carried out preliminary dose rate measurements in the experimental room of NOBORU. The measured values were in good agreement with the calculated ones within a factor of 2.

Shielding Design of a Neutron Beam Line “NOBORU” at JSNS/J-PARC