Shielding the LANSCE (Los Alamos Neutron Scattering Center) 800-MeV spallation neutron source

Conference · Fri Jan 01 04:00:00 EST 1988

OSTI ID:6906835

Russell, G J; Legate, G L; Robinson, H; Woods, R

Neutrons produced by medium-energy (800-MeV) proton reactions at the Los Alamos Neutron Scattering Center spallation neutron source cause a variety of difficult shield problems. We describe the general shielding questions encountered at such a spallation source, and contrast spallation and reactor source shielding issues using an infinite slab-shield composed of 100 cm of iron and 15 cm of borated polyethylene. The calculations show that (for an incident spallation spectrum characteristic of neutrons leaking at 90 degrees from a tungsten target) high-energy neutrons dominate the dose at the shield surface. Secondary low-energy neutrons (produced by high-energy neutron attenuation) and attendant gamma-rays add significantly to the dose. The primary low-energy neutrons produced directly at the tungsten source contribute negligibly to the dose, and behave similarly to neutrons with a fission spectrum distribution. 8 refs., 10 figs.

• Research Organization: Los Alamos National Lab., NM (USA)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 6906835
• Report Number(s): LA-UR-88-1987; CONF-880906-6; ON: DE88014437
• Country of Publication: United States
• Language: English

Related Subjects

654001* -- Radiation & Shielding Physics-- Radiation Physics
Shielding Calculations & Experiments
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ELECTROMAGNETIC RADIATION
ENERGY DEPENDENCE
GAMMA RADIATION
IONIZING RADIATIONS
MATERIALS
NEUTRON FLUX
NEUTRON LEAKAGE
NEUTRON SOURCES
PARTICLE SOURCES
RADIATION FLUX
RADIATION SOURCES
RADIATIONS
SHIELDING
SHIELDING MATERIALS