Excited atoms throw light on anti-hydrogen research

Excited atoms throw light on anti-hydrogen research
A positron beam line transports the positrons from the source into the main antihydrogen trap. Credit: Swansea University

Swansea University scientists working at CERN have published a study detailing a breakthrough in antihydrogen research.

The scientists were working as part of the ALPHA collaboration which is made up of researchers and groups from over a dozen institutions from all over the world, with the UK contingent led by Swansea University's Professor Mike Charlton.

The research, funded by the EPSRC, was obtained using apparatus at the Antiproton Decelerator facility at CERN, and has been published in the Nature journal.

The Experiment

The ALPHA team experiment shows how the scientists improved efficiency in the synthesis of antihydrogen, and for the first time succeeded in accumulating the anti-, which has allowed for greater scope in their experimentation.

Professor Charlton said: "When an excited atom relaxes, it emits light of a characteristic colour, the yellow colour of sodium street lights is an everyday example of this. When the atom is hydrogen, which is a single electron and a single proton, and the excited electron decays to the lowest energy state from a higher one, the discrete series of ultraviolet light emitted forms the Lyman Series, which is named after Theodore Lyman who first observed this over 100 years ago.

"The presence of these discrete lines helped to establish the theory of quantum mechanics which governs the world at an atomic level and is one of the corner stones of modern Physics.

"The Lyman-alpha line is of fundamental importance in physics and astronomy. For example, observations in astronomy on how the line from distant emitters is shifted to longer wavelengths (known as the redshift), gives us information on how the universe evolves, and allows testing models which predict its future"

This experiment is the first time the Lyman-alpha transition—when the hydrogen electron transitions between the so-called 1S and 2P state, emitting or absorbing UV light of 121.6 nm wavelength—has been observed in anti-hydrogen. Antihydrogen is the antimatter counterpart to hydrogen, and is comprised of a single anti-proton and a single anti-electron with the latter particle also known as a positron.

Excited Atoms

For this experiment, the physicists accumulated about 500 antihydrogen atoms in the trap. If they did nothing, they could hold these atoms for many, many, hours without loss. However, by illuminating the trapped atoms with various colours of UV light, the team could drive the Lyman-alpha transition and excite the antihydrogen atoms.

These excited atoms are no longer trapped within the apparatus and, being comprised of antimatter, promptly annihilate with the surrounding matter of the equipment and are detected.

This observation is significant as it is yet another test of a property of antihydrogen that is in good agreement with that of hydrogen. It is also a key step towards the production of ultra-cold , which will greatly improve the ability to control, manipulate and perform further precision studies on the anti-atom.

Professor Charlton said: "This represents another landmark advance in atomic physics, which should open the way to manipulation of the kinetic energies of the trapped anti-atoms

"While studies have continued at the Antiproton Decelerator facility at CERN, further refining these measurements and using the techniques to improve our understanding of the through spectroscopy, the ALPHA team will be modifying the apparatus in order to study the effect of Earth's gravity on the anti-atom. The next few months will be an exciting time for all concerned."


Explore further

New results show that matter and antimatter interact with light in precisely the same way

More information: Observation of the 1S–2P Lyman-α transition in antihydrogen, Nature (2018). DOI: 10.1038/s41586-018-0435-1 , https://www.nature.com/articles/s41586-018-0435-1
Journal information: Nature

Provided by Swansea University
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Aug 22, 2018
Won't be long before they collecting anti-hellium atoms. And then eventually...

anti-helium balloons...

...that go down.

Aug 22, 2018
Even if antihydrogen/antihelium had negative gravity (which they don't) a balloon full of the stuff would still float upwards.
(Well...if you can somehow keep it from turning into the most impressive explosion the planet has ever seen, that is)

Aug 22, 2018
Anti-protons require a negative charge which implies a rearrangement of quarks - this mean the down quark that is presently in the proton requires 3Down quarks in the anti-proton which means the anti-proton has a different energy than the proton - an unstable antiproton

Aug 22, 2018
Anti-protons require a negative charge which implies a rearrangement of quarks - this mean the down quark that is presently in the proton requires 3Down quarks in the anti-proton which means the anti-proton has a different energy than the proton - an unstable antiproton

What a bunch of bollocks. Quarks have anti-counterparts. A proton is made up of two up and a down quark - so an antiproton is made up of two anti-up and an unti-down quark.

Aug 22, 2018
antialias
Yes, but you see "Brevity is the soul of WIT" (phys·org, q.v.), not necessarily of science. But the science aspect to me is the development of long storage times of significant amounts of anti-hydrogen. Now we can start to look to see how many zeros start appearing to the right of measurement decimal points to determine how normal/anti symmetry-neutral the universe is.

The next step is storing the first anti-He atom. The first experimental generation happened in 2011, if I recall.

Aug 22, 2018
But the science aspect to me is the development of long storage times of significant amounts of anti-hydrogen.

1) Antiprotons can be stored in a magentic trap or using electric fields (I think the record is somewhere around 10 minutes). but since you can only get to such and such a degree of vacuum the stored stuff will eventually find something to annihilate with.
2) There is no readily available source of a reasonable amount of antiprotons. and since they all repel each other it becomes rather harder to store them the more you have. But you don't need many to perform measurements on (ideally you *want* to have one isolated atom to look at)

Storing anti-hydrogen atoms on the other hand is harder- because anti-hydrogen is electrically neutral (i.e. the magnetic/electric confinement works a whole lot less, but it can be done.The keyphrase here is "magnetic minimum neutral atom trap")

Aug 22, 2018
Anti-protons require a negative charge which implies a rearrangement of quarks ...snip...


Is that from the Fox News, science section.

Aug 22, 2018
"This experiment is the first time the Lyman-alpha transition—when the hydrogen electron transitions between the so-called 1S and 2P state... absorbing UV light of 121.6 nm wavelength—has been observed in anti-hydrogen... the team could drive the Lyman-alpha transition and excite the antihydrogen atoms... These excited atoms are no longer trapped within the apparatus"

Why are the excited atoms no longer trapped within the apparatus?

Aug 22, 2018
A definition of an anti-particle
Anti-protons require a negative charge which implies a rearrangement of quarks this mean the down quark that is presently in the proton requires 3Down quarks in the anti-proton which means the anti-proton has a different energy than the proton an unstable antiproton

What a bunch of bollocks Quarks have anti-counterparts A proton is made up of two up and a down quark so an antiproton is made up of two anti-up and an unti-down quark

A definition of an anti-particle in that it is opposite in charge of its counterpart the particle that in all simplicity it is in all reality a particle of opposite polarity that all it takes is its characteristics of polarity rearranging such that its two up quarks of internal naturality are removed an placed with two down quarks totalling a negative charge in totality creating a negative anti-proton of opposite plarity to its proton as in all reality a anti-particle is just opposite polarity

Aug 22, 2018
Anti-protons require a negative charge which implies a rearrangement of quarks - this mean the down quark that is presently in the proton requires 3Down quarks in the anti-proton which means the anti-proton has a different energy than the proton - an unstable antiproton

What a bunch of bollocks. Quarks have anti-counterparts. A proton is made up of two up and a down quark - so an antiproton is made up of two anti-up and an unti-down quark.


Correct. However, you are arguing with a complete moron. Ergo, it is a waste of time.

Aug 22, 2018
... A definition of an anti-particle in that it is opposite in charge of its counterpart the particle that in all simplicity it is in all reality a particle of opposite polarity that all it takes is its characteristics of polarity rearranging such that its two up quarks of internal naturality are removed an placed with two down quarks totalling a negative charge in totality creating a negative anti-proton of opposite plarity to its proton as in all reality a anti-particle is just opposite polarity

I've read that through three times and it seems to make no sense. I could be wrong in that but maybe try some punctuation next time to make a paragraph of several short sentences. These should each make grammatical sense in their own right, and not play with mixing a whole lot of present perfect progressive tense verbs together into a nasty mashup. Ideally these sentences, when read together, will build a coherent picture of what you are attempting to say. Just an idea.

Aug 23, 2018
The antiproton was first experimentally confirmed in 1955
granville583762> Anti-protons require a negative charge which implies a rearrangement of quarks

The existence of the antiproton with −1 electric charge, opposite to the +1 electric charge of the proton, was predicted by Paul Dirac in his 1933 Nobel Prize lecture. The positron is the antimatter electron, with its positive charge and opposite spin https://en.wikipe...tiproton
antialias_physorg> What a bunch of bollocks. Quarks have anti-counterparts. A proton is made up of two up and a down quark - so an antiproton is made up of two anti-up and an unti-down quark.

Really antialias_physorg, rubbishing the definition of an anti-proton – you cannot even spell unti-down quark, I suggest you start English lessons and horrors of horrors, may be even using a spell checker, you might even find unti-down is spelt anti-down

Aug 23, 2018
The polarity of the electric field does not an anti-particle make
There is no difference between a quark and its opposite number the anti-quark, its electric field is identical to the proton, the only difference antialias_physorg, is its polarity is equal to the electrons electric field in polarity and its physicality.
Seeing as antialias_physorg, the polarity of the electric field is the only difference in the proton that renames it by definition a anti-proton, as every property of the proton remaining equal, a difference in polarity does not an anti-particle make.

Aug 23, 2018
As a self confessed Cambridge graduate
antialias_physorg as a professed Cambridge graduate, where it is expected to argue ones corner and not to use expletives as an alternative to rationality of mind, I suggest you read through my comments antialias_physorg, you will not find one expletive in my inky text

Aug 23, 2018
A quark has never been observed triply or in isolation
Due to a phenomenon known as colour confinement, quarks are never directly observed or found in isolation; they can be found only within hadrons https://en.wikipe...ki/Quark
antialias_physorg:- in all that has been inkly typed so far concerning this ethereal quark, it has never been seen in isolation; that whether there is in all actuality an anti-quark or even simpler a negatively charged down-quark, it cannot be known for 100% certainty.

Aug 23, 2018
antialias_physorg as a professed Cambridge graduate

Erm..whut? Come off your meds, mate. I never said I am a Cambridge graduate (I think the closest I got to Cambridge was a two day visit during holidays when I was still going to highschool)

where it is expected to argue ones corner and not to use expletives as an alternative to rationality of mind

Rational arguments only work on other rational minds. Read: For you that leaves expletives.

you will not find one expletive in my inky text

That still leaves all the posts you've ever written as bollocks.

quark, it has never been seen in isolation

So? Every prediction made (e.g. that when the bottom quark was found that the top quark must also exist) has held so far. Unless you have a theory that beats that - go play somewhere else.

Aug 23, 2018
antialias_physorg as a professed Cambridge graduate

Erm..whut? Come off your meds, mate. I never said I am a Cambridge graduate (I think the closest I got to Cambridge was a two day visit during holidays when I was still going to highschool)

where it is expected to argue ones corner and not to use expletives as an alternative to rationality of mind

Rational arguments only work on other rational minds. Read: For you that leaves expletives.

you will not find one expletive in my inky text

That still leaves all the posts you've ever written as bollocks.

quark, it has never been seen in isolation

So? Every prediction made (e.g. that when the bottom quark was found that the top quark must also exist) has held so far. Unless you have a theory that beats that - go play somewhere else.

Found but not observed in isolation

Aug 23, 2018
Observing quarks in isolation
This is the thing antialias_physorg, quarks can be theorised with no evidence, they can be found indirectly but never observed whether it's in isolation or triply so although they are theoretically indisputably in the proton, until they are observed in isolation as a proton is observed in isolation, the theoretically indirectly detected quarks cannot be 100% until they are observed in isolation

Aug 23, 2018
The theoretical world of an unobserved quark in isolation
Concerning quarks in isolation containing the negative charge of anti-protons as if the quark is not 100% certain, this puts the source of the anti-protons negative charge in the theoretical world of an unobserved quark in isolation, as all we externally observe is the protons now negative charge not knowing with a 100% certainty whether it is the quarks that are totally responsible for the protons positive or negative charge.

Aug 23, 2018
Found but not observed in isolation

Again: So?

This is the thing antialias_physorg, quarks can be theorised with no evidence

That's why , after you make a theory you see what it predicts. Then you make experiments and see if the experiments come out as predicted. Et voila: They did.
This is what is called EVIDENCE (look up the word and its root. Marvellous what one can do when one actually understands the words one is using).

Aug 23, 2018
More fortunate than some
antialias_physorg> I never said I am a Cambridge graduate (I think the closest I got to Cambridge was a two day visit during holidays when I was still going to highschool)

That explains the joke antialias_physorg, "kings parade is not a shopping centre"; as when the traffic is clear it is only as the crow flies, during these summer days it is only elbow room with camera's flashing from every nationality in the world antialias_physorg - it is well worth a second visit.

P.S. In light of your fleeting visit, the joke is being returned to the quantum fluctuations antialias_physorg!

Aug 23, 2018
Ya might wann proofread what you write before hitting the 'submit' button. Because I'm fairly sure not even you can understand what you just wrote.

Aug 23, 2018
Putting the proverbial foot in it, socially
Ya might wann proofread what you write before hitting the 'submit' button. Because I'm fairly sure not even you can understand what you just wrote.

Benni can understand it antialias_physorg….some times when you cannot understand someone you're supposed to pretend you do understand – it's a social thing.
Antialias_physorg this comment is a conciliatory comment, and because you appear not to understand esoteric commentary, instead of quietly rereading, you jump the gun so to speak and put your proverbial foot in it, socially

Aug 23, 2018
They held 500 of the anti-atoms in containment for hours. They really exist whatever you want to call them.

Aug 23, 2018
Old_C_Code> They held 500 of the anti-atoms in containment for hours. They really exist whatever you want to call them.

This is the puzzle Old_C_Code, they exist in a cloud of anti-atoms for as long as they remain separate from normal atoms, so why do they not exist in galactic clouds in the vacuum?

Aug 23, 2018
What is different in anti-atoms that they cannot survive in galactic clouds in the vacuum?
Old_C_Code> they held 500 of the anti-atoms in containment for hours. They really exist whatever you want to call them.

granville583762> This is the puzzle Old_C_Code, they exist in a cloud of anti-atoms for as long as they remain separate from normal atoms, so why do they not exist in galactic clouds in the vacuum?

500, 1000 10million or 10trillion anti-atoms, it should make no difference because the same applies to normal protons in normal hydrogen as long as you keep them separate from anti-atoms you could have galactic clouds of normal atoms in the vacuum, so what is different in anti-atoms that they cannot survive in galactic clouds in the vacuum.

Aug 23, 2018
gran asks "why do they not exist in galactic clouds in the vacuum?"

They probably did/do during creation of stars, but always lose the battle with normal matter for some reason.

Aug 23, 2018
Where did they put the vacuum from their escape tunnel
gran asks "why do they not exist in galactic clouds in the vacuum?"

They probably did/do during creation of stars, but always lose the battle with normal matter for some reason.

I like this answer Old_C_Code, - when the anti-atoms are digging an escape tunnel from those pesky normal-atoms, where did they put the vacuum from their escape tunnel - they dug another tunnel in the vacuum and buried it!!!

Aug 23, 2018
No escape, the article says:

These excited atoms are no longer trapped within the apparatus and, being comprised of antimatter, promptly annihilate with the surrounding matter of the equipment

Aug 24, 2018
The reason no anti-atoms exist in the vacuum – they annihilate with the surrounding matter
No escape, the article says:

They held 500 of the anti-atoms in containment for hours They really exist whatever you want to call them

gran asks "why do they not exist in galactic clouds in the vacuum?"
They probably did/do during creation of stars but always lose the battle with normal matter for some reason

No escape, the article says: These excited atoms are no longer trapped within the apparatus and, being comprised of antimatter, promptly annihilate with the surrounding matter of the equipment

As good a reason why no anti-atoms exist in the vacuum – they "being comprised of antimatter, promptly annihilate with the surrounding matter of the equipment" - anti-atoms do not occur naturally in the vacuum, consequently any anti-atoms that do rarely do occur "annihilate with the surrounding matter"

Thanks Old_C_Code, you solved the mystery!

Aug 24, 2018
What is the difference in protons, electrons, anti-protons and positrons?

As far as can be ascertained it is not there electric field but their spin because although the proton and electron are oppositely charged the have a spin of 1 where as a anti-proton and positron have the same electric field but of again oppositely charged have a spin of -1

"electrons obtain magnetic moment with zero angular momentum and therefore produces no current loop to produce a magnetic moment 1925 Samuel A. Goudsmit - George E Uhlenbeck postulated electrons had intrinsic angular momentum a ball of charge have a magnetic moment if it were spinning such that the charge at the edges produced an effective current loop. This reasoning led to the use of electron spin describing intrinsic angular momentum http://hyperphysi....html#c5 "

A excellent postulation: but is this spin still actual spin, or mathematical spin

Aug 24, 2018
An excellent postulation: but is this spin still actual spin, or mathematical spin
As physical spin would provide the electron with momentum for its electric field there by producing a magnetic field, because either way the electric field requires momentum or the alternative is an independent electric and magnetic field requiring no momentum or physical spin!

Aug 24, 2018
I'm just a science layman, an engineer who follows science developments. Questioning heavy duty research of the cuff online is not what I do, or can do. Gran you are lost in the trees and can't see the forest, imo.

Aug 24, 2018
Old_C_Code> ]I'm just a science layman, an engineer who follows science developments. Questioning heavy duty research of the cuff online is not what I do, or can do. Gran you are lost in the trees and can't see the forest, imo.

Yes, I know Old_C_Code, can't see the wood for the trees - the magnetic field has got lost in the intrinsic spin of the electric field in actual spin or mathematical spin - plenty of trees to choose from.

Aug 24, 2018
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Aug 24, 2018
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