Akademik Veri Yönetim Sistemi
JOURNAL OF INSTRUMENTATION, cilt.1, sa.20 , ss.1-17, 2025 (Hakemli Dergi)
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.