Talk:Particle accelerator

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Contents 1 Frequently Ask Questions About Accelerators 2 Is this really still a stub? 3 Removed from article 4 Organization 5 Typos

[edit] Frequently Ask Questions About Accelerators

1. Q : What do different particle accelerators sound like when in operation?

A : Basically, you cannot hear the motion of the particles nor the sound produced by the collision with the target. The walls of the vacuum chambers are about one inch thick of solid metal, so they are great accoustic isolators. However, to operate an accelerator facility, a lot of electronics is needed. Just imagine a room full of computers and you will be close...

Umm... All of our particle accelerators at work are composed mainly of 1mm thick stainless tubing, nowhere near one inch thick. Many smaller and midsized electrostatic accelerators have moving charging belts or chains and actually are quite loud when in operation. Martyman 10:43, 16 Mar 2005 (UTC)

speaking as a former SLAC employee, i can tell you that most (all?) RF accelerators are either cooled by water (for room-temperature cavities) or by cryogenics (for superconducting cavities). the various pumps that run these cooling systems, along with the pulsed switch tubes in the klystrons usually generate one hell of a racket while the accelerator is operational.

Natelipkowitz 00:46, 6 December 2005 (UTC)

A tandem Van de Graaf makes a bang when there is a ten million volt spark, but they had to have a sound system for us to be able to hear it in the control room.

2. Q : Do particle accelerators have any characteristic oder or visual effect?

A : Yes in Ion implantation toxic odor when opened to atmosphere. Visual effects?

3. Q : Why do physicists create particle accelerators?

A : Particle accelerators are developed by physicists who want to get a better understanding of the fundamental laws of nature. When particles collide in a particle accelerator, physicists can see attributes of subatomic particles by using a bubble chamber (modern) or a cloud chamber (less modern, less expensive). The chamber will allow scientists to collect the path of particles after the collision. These paths tell physicists a lot.

Particle accelerators are used for much more than high end nuclear physics research. They are used in the fabrication of semiconductors, the treatment and diagnosis of cancer and production of medical radioisotopes to name a few uses. These more mundane everyday accelerators greatly outnumber the giant super colliders of sub atomic physics. Even a cathode ray tube in a television or computer screen is a very low energy particle accelerator. Martyman 10:43, 16 Mar 2005 (UTC)

4. Q : Can you cook food with a particle accelerator, like a microwave?

A : surely this is a joke. i'm sure physicists don't spend millions of dollars, and even more valuable technology, in building a particle accelerator, just to heat up their hot pockets...

Actually, I recall that one physicist stuck a glass of beer in the beamline of the bevatron to test the theory that cosmic rays where what caused bubbles to nucleate in it. It got him a brief write-up in "Discover" magazine (and the answer was "no, something else causes nucleation"). --Christopher Thomas 01:37, 22 June 2006 (UTC)

5. Q: What is the purpose of building extreamly large circular accelerators - like the one in Texas? Is the information that could be learned really worth the billions these devices cost? Themepark

Circular accelerators are built because particles pass through any given set of RF cavities many times, being boosted each time, unlike a linear accelerator, where they make only one pass through. This allows higher energy for a given size of accelerator. However, forcing particles to follow a curved path causes losses due to synchrotron radiation, which places an upper limit to the energy that can be attained by any given circular accelerator. Linear accelerators are used for lighter particles like electrons and positrons (which have more severe synchrotron losses in curved accelerators), and ring-shaped accelerators are used for proton/antiproton experiments and experiments that collide heavy atomic nuclei.

Whether or not these devices are worth the money depends on what goals are considered important when judging "worth". They are unlikely to produce data that has practical application, but they are the only way to test many aspects of our theories of how the universe works. In other words, they are "pure research" devices. --Christopher Thomas 17:48, 12 March 2007 (UTC)

6. Q: Is the amount of energy created when the collision occurs equal to the amount of energy put in to the process of acceleration? 83.146.14.113 17:04, 12 March 2007 (UTC)B Briggs

No. There are inefficiencies in the acceleration mechanisms (energy put into the RF cavities doesn't all end up in the accelerated particles, by a long shot; most of it probably ends up as heat). There are also losses due to synchrotron radiation in ring-shaped accelerators that cause energy to be drained from the accelerated particles (lost as x-rays). When particles collide, not all of the energy goes into producing new particles, and the vast majority of particles produced aren't the ones any given experiment is interested in (high-energy accelerators are built to produce heavy, exotic particles, but it's much easier for lighter particles to be produced, so many more are). --Christopher Thomas 17:48, 12 March 2007 (UTC)

[edit] Is this really still a stub?

This seems to me like a pretty complete layman's treatment of the subject. Shall we remove the stub template? It could perhaps use some additional wikifying, but it sure doesn't seem stubby to me. --Kgf0 18:03, 11 October 2005 (UTC)

Feel free to add....Scott 18:30, 11 October 2005 (UTC)

honestly, in my opinion this article is rather incomplete, very poorly organized (separate sections on synchrotron light and synchrotron radiation, for instance) and in need of attention. i will do it when i can find the time! Natelipkowitz 00:48, 6 December 2005 (UTC)

[edit] Removed from article

I have just removed teh following text from the article. I couldn't find anything online that backed it up. If anyone knows anything about it feel free to re-add it. --Martyman-(talk) 05:49, 26 November 2005 (UTC)

There is also a new larger accelerator being built in Sweden crossing over the border
into Switzerland. It will span in an underground tunnel under the border over 3 km and
has two different acceleration magnets at each end to help in extensive study of different
things done with the accelerator.

Well, Swededen and Switzerland don't border each other, so a 3km linac wouldn't help much. Looks like somebody was confused and/or writing a silly hoax. -- SCZenz 16:40, 26 November 2005 (UTC)

You know the thought that Sweden and Switzerland wheren't anywhere close to each other did cross my mind, but strangely it didn't click as evidence that this was a hoax. ;-) The big CERN accelerator is in a ring that crosses the Switzerland-France border, but this is not what they are talking about (not a linear accelerator 3km long). --Martyman-(talk) 21:06, 26 November 2005 (UTC)

[edit] Organization

It seems to me, on first looking back on this article to need help. High and low energy are related to how the energy is applied to the particles, but that is not the way to start the article. We should say something about the scale and use of high and low energy accelerators, describe some technology and then say what techniques have proven most useful for what types of accelerators.

I agree the article does need a good going over. There is also the problems of a confused terms in the article. I am under the understanding that a linear accelerator is any accelerator that does not follow a curved path, this would include large linacs, smaller electrostatic accelerators and could even be stretched to cathode ray tubes, etc. The term "linac" obviously a shortening of linear accelerator seems to be solely applied to large superconducting RF type accelerators, though is used interchangably in this article. --Martyman-(talk) 05:07, 20 January 2006 (UTC)

I think "linac" includes all strait-line accelerators that use radio frequency fields to accelerate the particles, at leas if they have high enough energy to induce nuclear reactions. I can't remember for sure, but I think the professors I worked with when I did my thesis used the temp to apply to the Luis Alvarez proton linear accelerator. I also believe the term was used to describe the second injector stage of the CERN PS. David R. Ingham 19:54, 22 January 2006 (UTC)

[edit] Typos

The last sentence of the first paragraph of Astrophysics is broken, too broken for me to figure out what it is meant to say.

Removed "Black Hole production". Not relevant to discussion of particle accelerators, per se. This should instead go into an article on exotic physics at colliders.--131.225.233.132 16:21, 11 September 2006 (UTC)