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Scientists confirm element 117

This superheavy was produced for the second time — and by a different team of researchers than four years ago — proving that ununseptium is real

By
9:32am, May 13, 2014

This is a view down the 120-meter (394-foot) long linear accelerator at the GSI Helmholtz Center for Heavy Ion Research in Darmstadt, Germany. It created the calcium-ions used in new tests that produced element 117. 

G. Otto, GSI

The second time’s the charm. For the second time in four years, scientists report creating a new element with 117 protons in its nucleus. That new report confirms element 117’s existence.

Both times, scientists reported making only a small amount. Several atoms. And they lasted for less than a second before breaking apart. But that was enough.

Scientists first claimed to make the element in 2010.The science community wanted to be sure that discovery was real, however, before celebrating its birthday. There was always the chance someone might have made a mistake interpreting the data.

The new announcement means chemists will likely soon be adding number 117 to their periodic table of the elements. The new entrant’s name? Unofficially, scientists are calling it ununseptium. Not terribly clever, it’s based on the Latin for one-one-seven. But that name is only temporary. Those who first created 117 should get a chance to rename it before long.

Uranium is the heaviest naturally occurring element on Earth (at least in substantial quantities). It’s number 92 on the periodic table. But for decades, scientists have been bombarding big elements with smaller ones. Their goal has been to briefly fuse them. That creates a superheavy. Depending on who you talk to, a superheavy is an either an element bigger than uranium or one more massive than rutherfordium (number 104).

For now, number 117 is the most massive element confirmed to exist. In 2006, researchers reported creating one slightly bigger: ununoctium, or number 118. But such superheavy elements must be created more than once, by different researchers. Until that happens, the scientific community will not formally accept that their existence is real. Ununoctium is still awaiting such a confirmation through a second set of tests.

The creation of element 117 began with another element, berkelium (number 97). For more than a year, researchers at the Department of Energy’s Oak Ridge National Laboratory, in Oak Ridge, Tenn., worked to make some 13 milligrams of almost pure berkelium. They shipped the radioactive element to Mainz University in Germany. There, researchers bombarded it with a high-energy beam of calcium ions. A small number of the smash-ups resulted in fusion reactions. A few atoms of element 117 emerged from those reactions.

The researchers didn’t actually “see” the new element. They deduced its creation by studying its radioactive decay. That’s when an atom sheds subatomic particles (here alpha particles). All radioactive elements, including number 117, decay. It means they break into smaller atoms or spit out subatomic particles. In the new tests, scientists quantified each successive decay of the original element and its breakdown products — known as daughters. That let them confirm that the short-lived parent must have been element 117.

In all, 72 scientists and engineers from 16 different research centers took part in the new project. They reported their achievement May 1 in Physics Review Letters.

Although element 117 was short-lived, scientists suspect some superheavies might be relatively long-lived. Such elements would exist in a so-called island of stability. Looking to find that island is one reason that scientists pursue this costly and time-consuming quest for ever-heavier elements.

Power Words

alpha particle  A type of ionizing radiation, physically equivalent to the nucleus of a helium atom (because it consists of two protons and two neutrons). Alpha particles carry away some of the energy that had been in the nucleus from which it had been emitted. That energy will be deposited into any material with which it collides. If alpha particles collide with living tissue, they can be very biologically damaging. Alpha particles are released by some many types of unstable radioactive isotopes, including plutonium, polonium, radium and uranium.

atom    The basic unit of a chemical element. Atoms are made up of a dense nucleus that contains positively charged protons and neutrally charged neutrons. The nucleus is orbited by a cloud of negatively charged electrons.

chemistry   The field of science that deals with the composition, structure and properties of substances and how they interact with one another. Chemists, the scientists who work in this field, use such knowledge to study unfamiliar substances, to reproduce large quantities of useful substances or to design and create new and useful substances.

element  (in chemistry)Each of more than one hundred substances for which the smallest unit of each is a single atom. Examples include hydrogen, oxygen, carbon, lithium and uranium.

engineer  A person who uses science to solve problems. As a verb, to engineer means to design a device, material or process that will solve some problem or unmet need.

fusion  The merging of two things to form a new combined entity. (in physics) The process of forcing together the nuclei of atoms. This nuclear fusion is the phenomenon that powers the sun and other stars, producing heat and forging the creation of new, larger elements.

ion     An atom or molecule with an electric charge due to the loss or gain of one or more electrons.

nucleus  Plural is nuclei. (in physics) The central core of an atom, containing most of its mass.

periodic table of the elements    A chart (and many variants) that chemists have developed to sort elements into groups with similar characteristics. Most of the different versions of this table that have been developed over the years tend to place the elements in ascending order of their mass.

physicist  A scientist who studies the nature and properties of matter and energy.

proton  A subatomic particle that is one of the basic building blocks of the atoms that make up matter. Protons belong to the family of particles known as hadrons.

radioactive  An adjective that describes unstable elements, such as certain forms of uranium and plutonium. Such elements are said to be unstable because their nucleus sheds energy that is carried away by photons and/or and often one or more nuclear particles.

radioactive decay  A process by which an element is converted into a lighter element through the shedding of subatomic particles (and energy).

subatomic    Anything smaller than an atom, which is the smallest bit of matter that has all the properties of whatever chemical element it is (like hydrogen, iron or calcium).

uranium   The largest naturally occurring element known. It’s called element 92, which refers to the number of protons in its nucleus. One form (isotope) is radioactive, which means it decays into smaller particles. The other form is stable.

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