Washington, September 25 (ANI): Researchers in Berkeley Lab's Nuclear Science Division and UC Berkeley have made a step forward in the quest to achieve an 'Island of Stability' among notoriously short-lived artificial elements, by confirming the production of the superheavy element 114.
The announcement comes ten years after a group in Russia at the Joint Institute for Nuclear Research in Dubna first claimed to have made the element.
Heino Nitsche, head of the Heavy Element Nuclear and Radiochemistry Group in Berkeley Lab's Nuclear Science Division (NSD) and a professor of chemistry at the University of California at Berkeley, and Ken Gregorich, a senior staff scientist in NSD, led the team that independently confirmed the production of the new element, which was first published by the Dubna Gas Filled Recoil Separator group.
Using an instrument called the Berkeley Gas-filled Separator (BGS) at Berkeley Lab's 88-Inch Cyclotron, the researchers were able to confirm the creation of two individual nuclei of element 114, each a separate isotope having 114 protons but different numbers of neutrons, and each decaying by a separate pathway.
"By verifying the production of element 114, we have removed any doubts about the validity of the Dubna group's claims," said Nitsche. "This proves that the most interesting superheavy elements can in fact be made in the laboratory," he added.
To create a superheavy nucleus requires shooting one kind of atom at a target made of another kind; the total protons in both projectile and target nuclei must at least equal that of the quarry.
Confirming the Dubna results meant aiming a beam of 48Ca ions - calcium whose nuclei have 20 protons and 28 neutrons - at a target containing 242Pu, the plutonium isotope with 94 protons and 148 neutrons.
The 88-Inch Cyclotron's versatile Advanced Electron Cyclotron Resonance ion source readily created a beam of highly charged calcium ions, atoms lacking 11 electrons, which the 88-Inch Cyclotron then accelerated to the desired energy.
According to Gregorich, "The high beam intensities from the 88-Inch Cyclotron, together with the efficient background suppression of the BGS, allow us to look for nuclear reaction products with very small cross-sections - that is, very low probabilities of being produced. In the case of element 114, that turned out to be just two nuclei in eight days of running the experiment almost continuously." (ANI)