Nuclear Medicine Physicist - Expert

Mercor; Sydney; On-site; AUD 90,000 - 130,000; Full time

Benefits offered by this job

null

Job summary

Mercor seeks experts in radiological safety to red-team frontier AI models. Your work involves creating and labeling prompts across benign, dual-use, and adversarial categories, evaluating model outputs against policy standards, and crafting reference answers with detailed technical reasoning.

This role emphasizes rigorous, written justification for every judgment and ongoing exposure to misuse scenarios. The position requires background in medical isotopes, shielding calculations, and

Qualifications

• This role requires deep expertise with medical isotopes and radiation safety.
• ,

Responsibilities

• Write challenging single-turn prompts at benign, dual-use, and adversarial levels.
• Evaluate model responses against a defined policy standard.
• Write the reference answer and technical reasoning.

Skills

Dual-use domain knowledge

Technical writing

Risk assessment

Education

Nuclear medicine / radiopharmacy background

Cyclotron or radiochemistry facility RSO

Medical physicist with brachytherapy custody

Radiopharmaceutical production and QC

Authorized Medical Physicist / Authorized User experience

Job description

About the work

Mercor is assembling a panel of radiological safety experts to red-team frontier AI models. The goal is to test whether a model can correctly judge the misuse potential of a technical request - answering legitimate questions fully while refusing genuinely dangerous ones.

You will:

• Write challenging single-turn prompts in your domain, labelled across three levels: benign, dual-use, and adversarial.
• Evaluate the responses that come back against a defined policy standard, and judge whether each was handled correctly.
• Write the reference answer - what a correct response looks like, and the technical reasoning for why.

This domain lives on the dual-use line more than most. The same isotope underpins cancer therapy and industrial radiography; the same shielding calculation protects a worker and conceals a source. A model that refuses a routine dose question is failing as badly as one that answers a question it shouldn't. Drawing that line reliably is why we need practitioners rather than generalists.

Background we're looking for

We’re looking for people who produce and handle medical isotopes - the legitimate-use half of the dual-use line, held as a real custody responsibility. What matters most is being able to tell a routine professional question from one that’s fishing for something else: the same activity and shielding figures that let a patient go home describe a source someone else

Examples of relevant backgrounds (ideally with red-teaming experience):

• Nuclear medicine or radiopharmacy physicist - therapy dosimetry, I-131, Lu-177 and Y-90 work, patient release criteria
• Cyclotron or radiochemistry facility RSO - target handling, PET isotope production, hot-cell operations
• Medical physicist with brachytherapy source custody - HDR and LDR sources, inventory and source exchange
• Radiopharmaceutical production and QC under GMP or an equivalent quality system
• Authorised Medical Physicist or Authorised User support on a medical radioactive materials licence

What this role demands beyond technical depth

This is writing-intensive work. Every judgment you make needs a written rationale that a non-specialist can follow. Prior technical writing, published research, or expert witness experience is a strong signal; please include a sample or link. You will also be reading and writing about misuse scenarios in your field for sustained periods. We brief experts on this in advance, and you can pause or step away at any point without penalty.

Before you apply

Your work here will not involve, and must not draw on, classified or export-controlled information, or anything covered by an NDA or prepublication review obligation.