CERN Achieves Alchemists’ Dream: Transmuting Lead into Gold, Briefly
For centuries, alchemists pursued the elusive dream of chrysopoeia, the ability to transmute base metals like lead into precious gold. While their methods, steeped in mysticism and rudimentary chemistry, fell short of this ambitious goal, modern science has, in a sense, realized this medieval fantasy. Scientists at the European Organization for Nuclear Research (CERN), utilizing the immense power of the Large Hadron Collider (LHC), have successfully transformed lead atoms into gold, albeit for a fleeting fraction of a second.
This remarkable achievement, though not a practical method for gold production, represents a significant scientific milestone. Physicists harnessed the LHC, the world’s largest and most powerful particle accelerator, to bombard lead atoms, causing them to shed three protons from their nuclei. Since the number of protons defines an element, this ejection effectively transformed the lead atoms, with their 82 protons, into gold atoms, which possess 79 protons.
While this isn’t the first instance of scientists artificially creating gold, the CERN researchers employed a novel mechanism involving near-miss collisions between lead nuclei. Uliana Dmitrieva, a physicist from the ALICE (A Large Ion Collider Experiment) collaboration at CERN, emphasized the significance of this approach. "The present analysis is the first to systematically detect and analyze the signature of gold production at the LHC experimentally," she stated. Dmitrieva, however, wasn’t involved in the study that goes into the new mechanism, which was published in the Physical Review Journals.
The process hinges on the fundamental definition of elements, which are characterized by the number of protons within the nucleus of their atoms. Lead atoms, with their 82 protons, and gold atoms, with 79, are distinct elements because of this difference in proton count. The CERN experiment exploited this principle by manipulating the proton count within the lead nuclei.
The experiment involved accelerating lead nuclei to an astounding 99.999993% of the speed of light within the LHC. At these extreme velocities, the electromagnetic fields surrounding the nuclei become intensely warped, creating bursts of light particles known as photons. Crucially, the transformation didn’t arise from direct collisions, which is how the collider typically operates. Instead, it was the interaction between these generated photons and the lead nuclei during near-miss events that triggered the proton shedding. This phenomenon is termed electromagnetic dissociation.
When the lead nuclei passed close enough to interact with the photons, they experienced a force strong enough to eject both protons and neutrons. Depending on the number of protons lost, the lead atoms transformed into different elements. If a lead atom lost no protons, it remained lead. Losing one proton transformed it into thallium, while losing two resulted in mercury. The coveted transformation into gold occurred when a lead atom shed three protons.
The experiment successfully produced all three heavy metals: thallium, mercury, and gold. However, the gold nuclei were highly unstable and disintegrated almost immediately, existing for less than a second. This fleeting existence underscores the challenges of creating stable gold through artificial means.
Despite this brief existence, the experiment produced nearly twice as much gold compared to previous attempts. Even so, the quantity remains infinitesimally small, trillions of times less than what a goldsmith would need to craft a single piece of jewelry. The experiment’s value lies not in its potential for gold production, but in its contribution to fundamental scientific knowledge.
John Jowett, an accelerator physicist from the ALICE collaboration, though not involved in the study, highlighted the broader implications of the research. "The results also test and improve theoretical models of electromagnetic dissociation which, beyond their intrinsic physics interest, are used to understand and predict beam losses that are a major limit on the performance of the LHC and future colliders," he explained. By refining these models, the research contributes to optimizing the performance of the LHC and future particle accelerators.
While medieval alchemists might be disappointed that this research offers no path to instant riches, it stands as a testament to the power of modern physics and the ingenuity of scientists. It also serves as a reminder that the pursuit of scientific knowledge often leads to unexpected discoveries and advancements.
The transmutation of lead into gold joins a long list of achievements accomplished at the LHC. One of the most celebrated breakthroughs was the discovery of the Higgs boson particle in 2012. This discovery confirmed the theoretical existence of a new field, the Higgs field, that gives mass to other fundamental particles like electrons. This discovery revolutionized our understanding of particle physics and validated the Standard Model, a theoretical framework that describes the fundamental forces and particles of the universe.
As the LHC continues to operate and gather data, scientists are poised to uncover even more secrets of the universe. The transformation of lead into gold, albeit fleetingly, serves as a compelling example of the transformative power of scientific inquiry and the potential for future discoveries at the world’s most powerful particle accelerator. It remains to be seen what the next groundbreaking discovery will be, but the pursuit of knowledge at the LHC promises to continue pushing the boundaries of human understanding.
