Big Ideas Lab: CAMS

Podcast: Big Ideas Lab (Mission.org)
Episode: CAMS
Date: November 18, 2025

Episode Overview

This episode dives into the pioneering work of the Center for Accelerator Mass Spectrometry (CAMS) at Lawrence Livermore National Laboratory. With immersive storytelling and direct accounts from scientists, listeners are taken inside investigations ranging from cracking cold cases with atomic precision to rewriting the timeline of North American prehistory. What emerges is a portrait of boundary-pushing science, powered by world-class technology and a deeply collaborative ethos.

Key Discussion Points & Insights

The Power of Accelerator Mass Spectrometry (AMS)

• CAMS is a world leader in measuring ultra-rare isotopes, which enables research in archaeology, national security, public health, and forensics. (03:23)
• Diverse expertise: The lab's staff, including a dozen PhDs across disciplines, contribute to a wide array of research using AMS’s unparalleled sensitivity.

  "We all come with different scientific backgrounds." — Bruce Buchholz (04:00)

AMS in Cold Case Forensics

British Columbia John Doe Case

• In 1968, detectives found a child's remains whose identity stumped authorities for decades (00:04–01:38).
• Detailed forensic work decades later—combining DNA analysis and AMS-based radiocarbon dating—revealed the child was actually about four and a half years old, not 7–9 as initially thought (01:03).
• Lawrence Livermore’s team used fallout from Cold War nuclear testing as a “bomb pulse” timestamp to pinpoint dates of birth and death:

  "It was actually amazing." — Bruce Buchholz (01:33)

• The case closure exemplified how modern scientific tools can bring closure to families even decades later.

Newfoundland Murder Case

• In 2007, AMS helped identify Temistoko Fernandez Casas, a murder victim whose remains had been discovered in the Canadian woods six years earlier (06:20–08:24).
• Key insight: Global nuclear testing increased atmospheric carbon-14, allowing researchers to date organic remains with tremendous precision if the individual died after 1955.

  "That pulse basically started in 1955, went up and reached a peak in 1963, and has been coming down since then." — Bruce Buchholz (07:39)

• Date of death estimated to ~1996 and birth to 1958–1962, narrowing down the ID window and allowing for closure in a 15-year-old case.

Instrumentation and Lab Culture

• CAMS utilizes a powerful 10 MV particle accelerator—repurposed from nuclear physics—making it unique among facilities focused on advanced radiocarbon work.

  "Some of the big machines like that were modified from their nuclear physics backgrounds to do AMS." — Susan Zimmerman (09:39)

• The mission encompasses not just science, but applications in national security and forensics.

  "So our mission... is all, I think, different from other labs that do AMS." — Susan Zimmerman (09:59)

Rewriting North American Prehistory

The White Sands Footprints Discovery

• Scientists used AMS to analyze seeds from aquatic plants embedded with ancient footprints in White Sands National Park, NM.
• The surprising result: The analyzed seeds—and thus the footprints themselves—date to between 21,000 and 23,000 years ago, overturning the previous consensus that humans arrived in North America only 13,000–16,000 years ago (13:24–14:01).

  "No one was expecting dates 23,000 years old." — Susan Zimmerman (14:01)

• Pollen dating confirmed the results, after technical hurdles in isolating sufficient, uncontaminated pollen.

  "It turned out that the pollen dates pretty much confirmed the rupia seed dates." — Susan Zimmerman (15:29)

• This work adds 7,000 years to the established timeline and challenges archaeologists to rethink human migration.

  "There has to be so much humility to say we don't know anything, anything about what people were doing..." — Susan Zimmerman (15:56)

Biomedical Breakthroughs

Dating the Age of Neurons

• AMS was used to date DNA in brain cells, leading to the discovery that most neurons do not renew—except for those in the hippocampus, which is vital for memory formation (16:44–17:10).

  "Do turn over, and hippocampus is where memories get transformed from short term to long term." — Bruce Buchholz (17:10)

• The technique enables detailed studies of neuron life spans and offers insights into neurobiology and diseases.

  "Some of the projects that we've been involved in really changed the way people think of things." — Bruce Buchholz (17:33)

Scientific Curiosity & Ongoing Innovation

• The team views scientific progress as an ongoing process, always looking for ways to extract more nuanced data and challenge assumptions.

  "We're always trying to figure out what we can do better, what kind of scientific measurements we can make that we can't do now." — Susan Zimmerman (17:58)

Notable Quotes & Memorable Moments

• On scientific humility:

  "There has to be so much humility to say we don't know anything, anything about what people were doing in the Western hemisphere for those 7,000 years..."
  — Susan Zimmerman (15:56)

• On technological advancement:

  "There’s just lots of things that can be done now that couldn’t be done 20 years ago. They're new tools all the time."
  — Bruce Buchholz (17:52)

• On the lab’s collaborative nature:

  "We all come with different scientific backgrounds."
  — Bruce Buchholz (04:00)

• Surprise in the evidence:

  "No one was expecting dates 23,000 years old."
  — Susan Zimmerman (14:01)

Important Timestamps

• British Columbia cold case intro (00:04–01:38)
• Overview of AMS and CAMS's multifaceted work (03:23–04:49)
• Bruce Buchholz describes AMS applications and composition of staff (04:00–04:49)
• Newfoundland cold case and the bomb pulse (06:20–08:24)
• Susan Zimmerman on White Sands footprints (10:40–15:56)
• Breakthrough in dating DNA in brain cells (16:44–17:16)
• Reflections on scientific curiosity and future innovation (17:52–18:23)

Episode Tone

The episode maintains a curious, awe-inspired, and collaborative tone, interspersed with rigor and humility. The scientists’ voices reveal both pride in their breakthroughs and an ongoing sense of wonder at how much remains to be discovered.

Summary prepared for those seeking the essential insights into this powerful episode, weaving together stories of forensic breakthroughs, cultural history, and scientific curiosity at CAMS.