Talk:Antiproton

Manufacture

How do they make antiprotons for use in the colliders? —Preceding unsigned comment added by 216.251.209.111 (talk) 15:28, 17 September 2007 (UTC)

Their formation requires energy equivalent to a temperature of 10 million °C, and Big Bangs aside, this does not tend to happen naturally. (from the article) -- Isn't the interior of the sun (a "natural" body) at 15 Million Kelvin, which would be high enough? 68.40.50.73 04:50, 17 November 2005 (UTC)

10 million C sounds wrong to me. Let me check on this. HEL 16:27, 30 September 2006 (UTC)

Setting M_P = k_B T I get a temperature of 10 trillion Kelvin (10^13 K). Antiproton freeze-out is going to happen at a somewhat lower temperature (factor of 20, rule of thumb?). HEL 13:29, 2 October 2006 (UTC)

Should I add Template::Antimatter? Its longer than the body text. Chad 07:49, 6 February 2006 (UTC)

"Antiprotons were routinely produced at Fermilab for collider physics operations in the Tevatron, where they were collided with protons." What does the word "they" in the second clause refer to? It sounds like "they" = antiprotons, but the sentence is about producing them. I don't think antiprotons are used to produce antiprotons. Mcswell (talk) 01:20, 29 November 2024 (UTC)

Andromeda

This really doesn't seem like the place to put this... You won't find that on any other particle page either I would think... --Falcorian ^(talk) 04:13, 1 June 2006 (UTC)

The antiproton article is still in Category: Andromeda (TV series). Since the Andromeda references have been removed, should this category be removed also? HEL 16:38, 8 October 2006 (UTC)

Reversion

Reverted to Sep 30 2006 version -- negatron is (rarely) used to refer to an electron, never to an antiproton. HEL 13:13, 2 October 2006 (UTC)

Antiproton production in cosmic rays?

We should mention something about antiprotons in cosmic rays. If I remember right, they have been detected in cosmic rays by detectors in space. Let me check and find a ref. HEL 13:35, 2 October 2006 (UTC)

Did it! I added a section on "Occurrence in Nature", about antiproton detection in cosmic rays. It's still a little rough; if anyone wants to improve it I would be grateful. I'm hoping to add more in the future, maybe a bit about discovery, and maybe clean up some kind of non-encyclopedic-sounding style in the intro ("Big Bangs aside"?) HEL 03:39, 7 October 2006 (UTC)

Good show. Only one piece of editing advice though: don't put linebreaks within paragraphs when you get to the edge of the edit box, just keep typing. When paragraphs are broken up over multiple lines it makes future editing harder and it makes changes more complicated to review with the diff functionality. But again, good job! — Saxifrage ✎ 08:34, 7 October 2006 (UTC)

Thanks for the tip! I'll be careful in the future. (I typed it up offline in pico which sticks in the linebreaks automatically.) HEL 15:09, 7 October 2006 (UTC)

Burst of energy?

The first sentence states: "any collision with a proton will cause both particles to be annihilated in a burst of energy". Can anyone quantify the form of this energy? By analogy, the annihilation of an electron and a positron produces (I believe) a pair of characteristic 511 keV photons.

Good question! In any kind of annihilation reaction like that, you get out a selection of whatever is allowed by the total energy and quantum numbers of the initial state. For electron-positron annihilation at low speeds (when you only have 2 x 511 keV of energy available), the only things lighter that you can annihilate into are photons or neutrinos. The pair of photons is by far the dominant mode (to get neutrinos you'd have to annihilate via a W or Z boson; they're heavy so their contribution is very suppressed at these low energies).

For proton-antiproton annihilation at low speeds you've got 2 x 938 MeV of energy. I would expect the dominant annihilation mode by far would be via the strong interaction. Below the mass of the proton you've got the pions, kaons, eta, rho, and omega (at least). These are all unstable and decay down almost entirely to pions, muons+neutrinos and photons; the charged pions decay to muon+neutrino and the neutral pions decay to photon pairs; the muons finally decay depending on their charge to electron + 2 neutrinos or positron + 2 neutrinos. Unlike the electron-positron annihilation, you would typically get a good handful of final-state particles, so they wouldn't be monoenergetic.

I'm theorizing all of this; does anyone have more direct experience or references? HEL 20:26, 1 November 2006 (UTC)

Equations

I think they is something wrong with the equations. I can't figure what they are supposed to represent.Headbomb (talk) 00:05, 12 April 2008 (UTC)

Second Paragraph

The second paragraph says interactions energetic enough to produce antiprotons don't really happen in nature. I think this is false, or if it is true, should be reworded to avoid confusion. Antiprotons are produced in nature all the time, after all.

Naming

If the antielectron is called the positron, why is the term "antiproton" preferred over "negatron?" Shouldn't there be a consistent naming system? 71.203.66.120 (talk) 22:01, 25 November 2011 (UTC)

You can wish for a consistent naming system, but in reality objects that are discovered early on in a field get well-known names that don't fit into later schemes. It's not Wikipedia's job to try to change this. --Strait (talk) 14:35, 30 November 2011 (UTC)

Uh, I never said it was. I was asking in reference to science. 71.203.66.120 (talk) 19:40, 22 March 2012 (UTC)

External links modified

Hello fellow Wikipedians,

I have just modified one external link on Antiproton. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:

• Added archive https://web.archive.org/web/20110822150631/http://www.engr.psu.edu/antimatter/Papers/pbar_med.pdf to http://www.engr.psu.edu/antimatter/Papers/pbar_med.pdf

When you have finished reviewing my changes, please set the checked parameter below to true or failed to let others know (documentation at {{Sourcecheck}}).

This message was posted before February 2018. After February 2018, "External links modified" talk page sections are no longer generated or monitored by InternetArchiveBot. No special action is required regarding these talk page notices, other than regular verification using the archive tool instructions below. Editors have permission to delete these "External links modified" talk page sections if they want to de-clutter talk pages, but see the RfC before doing mass systematic removals. This message is updated dynamically through the template {{source check}} (last update: 5 June 2024).

• If you have discovered URLs which were erroneously considered dead by the bot, you can report them with this tool.
• If you found an error with any archives or the URLs themselves, you can fix them with this tool.

Cheers.—InternetArchiveBot (Report bug) 17:54, 15 October 2016 (UTC)

Out of Date

References the tevatron which is inactive. — Preceding unsigned comment added by 50.83.215.81 (talk) 03:20, 10 March 2018 (UTC)

"Anti Protons (Andromeda)" listed at Redirects for discussion

An editor has asked for a discussion to address the redirect Anti Protons (Andromeda). Please participate in the redirect discussion if you wish to do so. –LaundryPizza03 (dc̄) 07:12, 25 April 2020 (UTC)

We should call antiprotons contons

CosmicMinun59 (talk) 05:24, 24 September 2024 (UTC)