Accelerated Protons and Personnel Doses Don Cossairt, Radiation Protection Manager, ESH&Q Section January 22, 2014

Ancient history before MiniBooNE & NuMI

Same Graph Enlarged

New Idea! Normalize Dose to Booster Protons Tevatron Collider era involved small doses. Antiproton target is physically small. Beam intensities (not collider luminosities!) were rather low. Booster Neutrino Beam (MiniBooNE) came on line in 2002. NuMI came on line in 2005. Clearly moving from an era of low to high beam intensities BUT MORE beam power. Entire Fermilab accelerator-based program uses 8 GeV protons. The scientific “product” is tied to 8 GeV proton production. Normalize doses to 8 GeV protons accelerated. We started doing this in 2005.

Normalizing Dose to Booster Protons WARNING: This is not a perfect figure-of-merit! Nearly all dose is due to work on activated components! Nearly always have NO dose from prompt radiation. This means dose is received when the beam is not on during major shutdowns. What happens if a shutdown involves: Many maintenance tasks? Long time - no beam? Must only use this over the long, not the short, term.

Doses are largely “out-of-phase” with beam delivery.

Normalizing Dose to Booster Protons

Big Picture – Annual Doses

Overall Conclusions During FY12 – FY13 Shutdown managed to keep doses within ranges experienced in recent years. This was done in spite of a extremely huge amount of work done on the accelerators. Other talks will describe this huge body of work. Will keep monitoring doses/8 GeV protons. Heroic efforts of many people achieved this!