NuMI Tritium Experience and Personal Observations. Rob Plunkett Fermilab DUSEL Beam Working Group October 27, 2008. Brief Historical Summary. Radiology/groundwater was always of first importance in NuMI beamline design.
Fermilab DUSEL Beam Working Group
October 27, 2008
Collect chiller condensate
Dry air to upstream decay tunnel
Graphic from Jim Hylen, as are all similar.
There is a reservoir of stored tritium as well as instantaneous production
A year’s worth of Tritium instantaneous production
This factor of 0.6 due to chase dehumdifiers
-8 cm2/s instantaneous production
Jim Hylen’s simple 1-D target hall diffusion model for various steel diffusion constants
Note lower diffusion constants seem more likely from literature at our temperatures
Comparing Models with Decay Pipe Data (Lundberg) instantaneous production
Use MARS to extrapolate closer to pipe
Diffusion constant about 1E-6 cm**2/sec, not unreasonable
One of numerous cross-sections used in LBL model instantaneous production
Continuous grid defined along length
of tunnel, with smooth junctions between
Concrete parameters will be taken from
our own measurements of simulated shielding
Water flow vector diagram
Have form from MARS for z-dependence of source term.
Expect results soon.