The Russian lab’s recipe
for making new superheavy elements begins with expensive ingredients: rare,
heavy isotopes of calcium and of an existing heavy element like plutonium. When
the two kinds of atoms collide at high speed, they sometimes fuse into a new
superheavy one. Here are six key steps.
1. BAKE a solid
calcium compound at 1,300 degrees Fahrenheit in an oven (shown here with its
clamshell cover off). The calcium vaporizes, forming a gas that can be shaped
into a high-energy beam.
· 2. IONIZE the calcium
atoms by stripping off some of their electrons in a kind of microwave oven (red
cylinder). The positively charged ions can now be accelerated by electric and
magnetic fields.
3. ACCELERATE the ions in a pie-shaped
cyclotron. Here you’re at the center, where the ions come in. The dark wedge of
an electrode assembly, five feet wide, is pointing at you from the mouth of a
copper-clad pipe, which generates a strong electric field. Under its sway, the
calcium ions spiral out through the hollow electrodes
4. EXTRACT the
calcium ions from the outer rim of the cyclotron, and use magnets to channel
them down this tube in a four-inch-wide beam. They’re traveling at 67 million
miles an hour, or a tenth the speed of light.
5.SMASH the calcium
ions into a spinning target. It’s the crinkly foil barely visible just inside
the rim of the brass wheel. The foil is coated with plutonium or another heavy
element—which one depends on what new element is being cooked.
6.DETECT the
new element. It’s the needle in the haystack of debris coming out the back of
the foil target. The first step at Dubna is to catch all that in a disk of
red-hot graphite, slowing it down for analysis.
Creation of 115 element
A calcium-48 ion is accelerated to a high velocity in a
cyclotron and directed at an americium-243 target. The accelerated calcium-48
ion collides into an americium-243 target atom (above) and creates the new 115
element that begins decaying with the emission of alpha particle into element 113.
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