Электронный каталог

Статья

Zamora-Saa, J.A.
The SND@LHC Neutron Shielding / J.A.Zamora-Saa, N.Polukhina, [a.o.]. – Text : electronic // Journal of Instrumentation. – 2025. – Vol. 20, No. 12. – P. T12002. – URL: https://doi.org/10.1088/1748-0221/20/12/T12002. – Bibliogr.: 9.

This paper presents the design, construction, and simulation-based validation of the ColdBox, a combined neutron shielding and insulating enclosure for the Scattering and Neutrino Detector at the LHC (SND@LHC). The emulsion films in the detector’s target region require protection from the intense neutron radiation background and a stable environment of 15 ± 1 ◦C and 50–55 % relative humidity for long-term stability. The ColdBox meets these requirements through a dual-layer structure: an external 5 cm plexiglass wall to moderate fast neutrons, and an internal 4 cm layer of borated polyethylene (with 35 % boron content) to capture thermal neutrons. The mechanical design, based on a robust aluminum frame, accommodates the constraints of the TI18 tunnel. FLUKA simulations were used to optimize the shielding configuration, showing a significant reduction in the neutron flux, with a simulated ratio of shielded to unshielded thermal neutron fluence of 2.3 × 10*−*3 . This result is consistent with initial measurements from BatMon detectors. The design also provides a sealed volume for a cooling system to maintain the required temperature and humidity, ensuring the necessary conditions for the emulsion films’ integrity.