Nuclear Science Seminar Speaker Schedule Sign Up

Current Schedule

Speaker = Dr. Jaclyn Gates of LBNL Heavy Element Group

Host = Kathi Domnanich domnanic@frib.msu.edu

When = 2025-03-26 Wednesday

Where = FRIB 1300

Please feel free to sign up below, but note that some slots may need to be re-assigned to accommodate those with a specific need to meet the speaker. If this happens, the Admin or Speaker Host will reach out to you via email.

Title = Toward Pursuing New Superheavy Elements

Abstract

In the past two decades, significant progress has been made with the discovery of elements Z=114-118 through reactions between 48Ca beams and actinide targets, achieving production rates of atoms-per-day or more. Unfortunately, the pursuit of elements beyond Oganesson (Z=118) faces substantial challenges, with no new elements have been discovered in the last 15 years. The synthesis of elements with Z=119 or 120 using 48Ca would necessitate targets of Es (Z=99) or Fm (Z=100), but these elements cannot be produced in sufficient quantities. This limitation necessitates exploring new reaction pathways.

Numerous theoretical studies have aimed at predicting production rates for new elements using actinide targets and heavier ion beams. While these models reliably reproduce excitation functions for SHE production with 48Ca beams, predictions diverge significantly for reactions involving heavier beams. For instance, the predicted cross section for reactions to produce Z=120 vary by more than three orders of magnitude and tens of MeV. These discrepancies hinder experimental efforts, as the low expected cross sections suggest the detection of only one event every few weeks or months under ideal conditions.

Berkeley Lab has been proactively addressing these challenges to push beyond E118. By testing theoretical predictions, we have begun the 50Ti+244Pu experiment to understand the impact of using 50Ti instead of 48Ca beams on cross sections. This presentation will highlight significant upgrades to our experimental facilities, including ion sources, target setups, detectors, and electronics, aimed at enhancing our capability to produce and detect elements beyond E118. We will also present the initial results from the 50Ti+244Pu experiment, showcasing our progress in this ambitious endeavor.

Relevant background with commentary from Speaker:

• From past to future in the science of super heavy elements by: Yuri Oganessian
• Physics Viewpoint: A Route Toward the Island of Stability
• Toward the Discovery of New Elements: Production of Livermorium (𝑍=116) with 50Ti
• Super-heavy nuclei