Antihydrogen at CERN, 20 years and going strong

Antihydrogen at CERN, 20 years and going strong
The ALPHA experiment, one of five experiments that are studying antimatter at CERN. Credit: Maximilien Brice/CERN

Twenty years ago a team of scientists at CERN led by Walter Oelert succeeded in producing the first atoms made of antimatter particles.

The nine atoms of antihydrogen – the antimatter counterpart of the simplest atom, hydrogen – were made at CERN's Low Energy Antiproton Ring (LEAR) facility. This world premiere happened exactly 30 years after the discovery of the antiproton and opened a new chapter in the study of antimatter.

Comparisons of hydrogen and antihydrogen atoms constitute one of the best ways to make precise tests of differences between matter and antimatter. Their spectra are predicted to be identical, so any tiny differences would open a window to new physics, and could help in solving the antimatter mystery.

The atoms produced in 1995 remained in existence for about 40 billionths of a second, travelling for 10 metres at nearly the speed of light before being annihilated by ordinary matter and producing the signal that showed the anti- had been formed.

Seven years later, CERN's Antiproton Decelerator (AD) made headlines around the world when the ATHENA and ATRAP experiments successfully produced large numbers of for the first time.

Today, the AD serves five experiments that are studying antimatter in different ways: AEgIS, ALPHA, ASACUSA, ATRAP and BASE.

ALPHA – ATHENA's successor – is specifically designed to trap antihydrogen particles for longer than its predecessors, so they can be studied in finer detail than ever before. The ALPHA collaboration has already measured the electric charge of an antiatom to a much higher precision than before. The ASACUSA collaboration, which also has high-precision studies of antihydrogen in its sights, has demonstrated the first-ever production of a beam of antiatoms.

Earlier this year further advances were made when the Baryon Antibaryon Symmetry Experiment (BASE) reported the most precise comparison of the charge-to-mass ratio of the proton to that of its antimatter equivalent, the antiproton. The study, which took 13,000 measurements over a 35-day period, showed that protons and antiprotons have identical mass-to-charge ratios.

The AEgIS experiment, which has just started operation this year, is designed specifically to measure the gravitational interaction of antimatter. Another, future experiment, GBAR, will make similar investigations.

These recent successes mark a growth in antimatter research that CERN's AD can no longer keep up with, as more and more low-energy antiprotons are needed for experiments. An upgrade to the AD, called ELENA, will become operational in 2017. This is where GBAR will be installed.

ELENA will decelerate the antiprotons from the AD still further, allowing many more to be trapped by the experiments. With the additional ability to serve four experiments almost simultaneously, ELENA will usher in a new era in the investigation of the relationship between matter and in the universe.

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Sep 24, 2015
Here's what I'm waiting for: A search vehicles enters into an anti-matter galaxy. problem studied for centuries. Final results, anti-mater is matter with a different polarity of the unit of matter that rotates. Everything is formed by these unknown "+" and "-" with units defined by the effect of gravity? To compensate, it is shown that gravity is only a superposition of each of these [+1,-1] and isomorphic to a 4D unit-less space. With an understanding, that charges will always comply to form groups rather than turbulence. The energy release from a great distance is divided equally about a sphere, i.e gravity & prob(anti)

Sep 24, 2015
What are we looking for? Magic? All I see is + or - defined using poor choices for universality. This point in physics is defined from the Top Down not the Bottom up, outside of classical logic . GR is a mathematical and physical atrocity; therefore, this appears to be the actions of a confused people.

Anyone out there wish to publish my thinking?

Sep 24, 2015
You may imagine the results of this experiment in your head, in slow motion, just thinking how the rotating opposites will react, not to mention the relative particles velocities, the fields are clearly defined at any point in time. You find the stability point and the radiated energy from the motion of these charges, typically at levels ... anyway, ... that's how I see it. Only need to look at the motion of one charge, I have a mirror. I can see everything. At that instant, add 'em up, total spectrum ...

Sep 24, 2015
I'm thinking this computer design might be less this egg-hunt. Think of how many bits translated within the stream to define a graphic to peer at any point in space time. Run it forward and backwards to any precision. There is of +/- infinity. Since there are no units, get it. pick a map! present map streaming, any location, upon any display. How about instrumentation controls, molecular controls, communication!?? Does any one wish to give me algorithmic selective streaming, built into the hardware to stream any ply of this space time, selective controls for all views ... oh, we got that! Guess I better pick a language; java, ugh,; VS, ok; ruby best choice. Translate to HDL then into ...

Sep 24, 2015
Whoa nelly. Think you're going off the rails here Fuzzy.

Sep 24, 2015
Imagine, seeking understanding, from the perspective of the turbulent, to defined a unit, not yet understood anywhere within modern physics of any flavor! We lag in actual acuity. Knowledge, only from the edge of the blade, denies the real value of the blade or even its necessary existence! Better to know every atom of the blade and what the "undefined measure", of polarity and scale really are? Try an isomorphic mathematical identity! You are looking in the wrong places, try logic and certainty. Do not seek to deny or describe the "+" and the "-" with any other description is not better, without misunderstood units? So why not a unit-less isomorphism

Sep 24, 2015
Like I once said, don't just stare star at a mirror, just a ghost response backward in time! just kidding ... reflective, absorbed, its actually funny looking holograph, best would be a set of spheres for every point of our body, oops, that's what light does, ..., no magic. Simple summation. go figure..

Sep 24, 2015
The precision of the mind should define the precision of instruments and what information is best defined to describe any specific molecular structure's spectrum and/or response. Since one defines the other, with just +1 and -1 within a 4D space, define it's interaction. Just create molecular plys. They overlay, i.e. superimpose. Please, where am I wrong? Anti-Hydrogen, dude, we get that. Go play in propulsion or som'n like that. Here, take my last remarks with you, seriously.

Sure, go ahead, play with the 4D calculation you may create, then reproduce upon some "Frankenstein" matter. I don't care. But there are more useful computer searches. Like define this molecular structure, just from plys of "+" and "-". Do I really need to do the work, or will someone mention my name just before they take over the world. I rather sanity.

Sep 24, 2015
only 2 balls!

Sep 24, 2015
go play, play safely

Oct 21, 2015
"This world premiere happened exactly 30 years after the discovery of the antiproton and opened a new chapter in the study of antimatter."

More like 40 years. 1995-1955 = 40. Note that it was predicted even earlier by Paul Dirac in 1933.

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