Good news! Amazing stuff!
"... The heaviest abundant element known to exist is uranium, with 92 protons (the atomic number "Z"). But scientists have succeeded in synthesizing superheavy elements up to oganesson, with a Z of 118. Immediately before it are livermorium, with 116 protons and tennessine, which has 117.
All have short half-lives—the amount of time for half of an assembly of the element's atoms to decay—usually less than a second and some as short as a microsecond. Creating and detecting such elements is not easy and requires powerful particle accelerators and elaborate measurements.
But the typical way of producing high-Z elements is reaching its limit. In response, a group of scientists from the United States and Europe have come up with a new method to produce superheavy elements beyond the dominant existing technique. ...
Theoretical models of the nucleus have successfully predicted the production rates of superheavy elements below oganesson using actinide targets and beams of isotopes heavier than 48-calcium. These models also agree that to produce elements with Z=119 and Z=120, beams of 50-titanium would work best, having the highest cross sections. ...
The discovery represents the first time a collision of non-magic nuclei has shown the potential to create other superheavy atoms and isotopes (both), hopefully paving the way for future discoveries. About 110 isotopes of superheavy elements are known to exist, but another 50 are expected to be out there, waiting to be uncovered by new techniques such as this."
Using the 88-Inch Cyclotron accelerator at Lawrence Berkeley National Laboratory, the team produced a beam that averaged 6 trillion titanium ions per second that exited the cyclotron. These impacted the plutonium target, which had a circular area of 12.2 cm, over a 22-day period. Making a slew of measurements, they determined that 290-livermorium had been produced via two different nuclear decay chains.
"This is the first reported production of a SHE [superheavy element] near the predicted island of stability with a beam other than 48-calcium," they concluded. The reaction cross section, or probability of interaction, did decrease, as was expected with heavier beam isotopes, but "success of this measurement validates that discoveries of new SHE are indeed within experimental reach."
"... In practice, of course, it’s incredibly difficult. It can take trillions of interactions before two atoms fuse successfully, and there are limitations on what elements can reasonably be turned into a particle beam or target. ..."
From the abstract:
"The 244 Pu (50 Ti ,𝑥𝑛) 294−𝑥 Lv reaction was investigated at Lawrence Berkeley National Laboratory’s 88-Inch Cyclotron. The experiment was aimed at the production of a superheavy element with 𝑍≥114 by irradiating an actinide target with a beam heavier than 48 Ca. Produced Lv ions were separated from the unwanted beam and nuclear reaction products using the Berkeley Gas-filled Separator and implanted into a newly commissioned focal-plane detector system. Two decay chains were observed and assigned to the decay of 290 Lv. The production cross section was measured to be 𝜎prod=0.44(+0.58−0.28) pb at a center-of-target center-of-mass energy of 220(3) MeV. This represents the first published measurement of the production of a superheavy element near the “island of stability,” with a beam of 50 Ti and is an essential precursor in the pursuit of searching for new elements beyond 𝑍=118."
A New Way to Make Element 116 Opens the Door to Heavier Atoms (original news release)
To make element 116, researchers fused isotopes of titanium and plutonium.
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