First Precise Measurement of Antihydrogen

The best science — the questions that capture and compel any human being — is enshrouded in mystery. Here’s an example: scientists expect that matter and antimatter were created in equal quantities shortly after the Big Bang. If this had been the case, the two types of particles would have annihilated each other, leaving a Universe permeated by energy.

As our existence attests, that did not happen. In fact, nature seems to have a one-part in 10 billion preference for matter over antimatter. It’s one of the greatest mysteries in modern physics.

But the Large Hadron Collider is working hard, literally pushing matter to the limit, to solve this captivating mystery. This week, CERN created a beam of antihydrogen atoms, allowing scientists to take precise measurements of this elusive antimatter for the first time.

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Hmmm, I was under the impression it had been measured before.

I guess the key news here is the precision.

“In 2010, the ALPHA team captured and held atoms of antihydrogen for the first time. Now the team has successfully created a beam of antihydrogen particles. In a paper published this week in Nature Communications, the ALPHA team reports the detection of 80 antihydrogen atoms 2.7 meters downstream from their production.”

They also measured its charge.

dv said:

Hmmm, I was under the impression it had been measured before.

I guess the key news here is the precision.

There have been oodles of measurements of antiprotons and positrons. There have even been measurements of exotic atoms where positrons orbit holes in crystals and where muons orbit protons. But this is the first I’ve heard of of measurements where positrons orbit antiprotons. This is darn difficult to produce, and it’s taken a lot of effort at the Large Hadron Collider to generate enough of these anti-hydrogen atoms and slow them down to non-relativistic speeds. No earlier particle accelerator has been able to do it.