jjgreen 372 days ago [-]
I’ve always imagined that the adjective was needed because under a desk somewhere, perhaps pedal powered, was a “small hadron collider”

Robert E. A. Harvey, Comment on The Register, 28th December 2011


InclinedPlane 372 days ago [-]
There are lots of small hadron colliders. Hadrons are just composite particles made up of quarks and held together by the strong force. This includes "exotic" particles like mesons and high energy baryons, but it also includes the "mundane" baryons such as protons and neutrons. So technically any proton accelerator is a hadron collider. Which includes the first cyclotron, a proton accelerator built in 1932 that was only 27 inches across, a very "small hadron collider" indeed.
yborg 372 days ago [-]
Dr. Raymond Stantz: You know, it just occurred to me that we really haven't had a successful test of this equipment.

Dr. Egon Spengler: I blame myself.

Dr. Peter Venkman: So do I.

Dr. Raymond Stantz: Well, no sense in worrying about it now.

Dr. Peter Venkman: Why worry? Each one of us is carrying an unlicensed nuclear accelerator on his back.

hyperion2010 372 days ago [-]
Try A. E. van Vogt, Slan, 1946 for even more precient.
saagarjha 373 days ago [-]
> Colliding electron and positron beams could have implications in fundamental physics. For example, they could create a higher rate of Higgs bosons than the LHC can, allowing physicists to better study its properties.

Didn't the Large Electron-Positron Collider fail to detect evidence of the Higgs Boson?

mnl 373 days ago [-]
It got close, but it was limited by its design/diameter, such are the woes of synchroton radiation and accelerating the lighter charged particles. As far as I know they pushed its limits all they could (burning it) before shutting it down to replace it with the LHC. Too bad really, as the nicest accelerator for studying the properties of a Higgs is an e+e- collider and at some point at least one will/should be built. The LHC was built because something new had to show up at around 1TeV tops, it was either a Higgs boson or new physics (not all the energy of the pp collision is available for say a qq collision, because quarks are in a bound state, 14 TeV for pp at the LHC means approx 2 TeV for Higgs or new stuff).
magicalhippo 373 days ago [-]
> Didn't the Large Electron-Positron Collider fail to detect evidence of the Higgs Boson?

It didn't produce a negative result. In fact, they were seeing some small hints of something around 114 GeV right as they shut down for the LHC construction.

tempay 373 days ago [-]
(Just for completeness)

The hints at 114GeV in LEP were very subtle and have since been shown to be a statistical fluctuation (which is unsurprising). The Large Hadron Collider (LHC) has observed the Higgs boson at 125GeV. This mass is too high for LEP to have ever seen without further upgrades to boost it's energy and there was no reason to expect it to be as close as it is to the LEP energy. It could easily have been 200GeV+ and well outside of LEP's capabilities.

The advantage of the LHC is that is was capable of much higher energies due to being a proton collider (currently 13000GeV), though this comes at the cost of being "messier" to analyse the data. Additionally, continuing to run LEP to check would have further delayed the LHC which would have been very expensive.

based2 372 days ago [-]

"On 4 July 2012, the ATLAS and CMS experiments at CERN's Large Hadron Collider announced they had each observed a new particle in the mass region around 126 GeV. This particle is consistent with the Higgs boson predicted by the Standard Model."



"LEP – the largest electron-positron accelerator ever built – was dismantled in 2000. Its 27-kilometre tunnel now hosts the LHC"



saagarjha 372 days ago [-]
That says the LHC found it, not the LEP.
vichu 373 days ago [-]
No, it succeeded in confirming the existence of the Higgs boson. In fact, that's largely the reason Higgs and Englert were awarded the Nobel Prize in Physics in 2013.
magicalhippo 373 days ago [-]
LEP[1] did no such thing, you're talking about the LHC.

[1]: https://en.wikipedia.org/wiki/Large_Electron%E2%80%93Positro...

seiferteric 372 days ago [-]
Wow, I misread the OPs comment as the LHC also and thought I was experiencing the mandela effect haha.
orbifold 373 days ago [-]
No the LHC is a Large Hadron Collider, the previous collider was LEP a Large Electron Proton collider. They plan to build a linear electron proton collider similar to SLAC at some point.
leereeves 373 days ago [-]
Positron (the antimatter counterpart to the electron) not Proton (the positive particle in the nucleus of ordinary atoms).
magicalhippo 373 days ago [-]
Is this a variant of plasma wakefield accelerator, or something else?

If so, staging is an issue from what I understand. Even at 100GeV/m, you'll need many stages to reach interesting TeV territory, so this is a crucial aspect if it wants to beat the LHC.

Some relevant discussion on PhysicsForums: https://www.physicsforums.com/threads/two-stage-electron-wak...

tgragnato 373 days ago [-]
I read the pdfs but didn't dig in too much, however the main difference seems to be the generation of a beam of positrons instead of electrons.
danesparza 373 days ago [-]
I couldn't find it in the article (perhaps I overlooked it) -- but what do they mean by 'mini'? Especially considering the LHC has a circumference of 16 miles...
magicalhippo 373 days ago [-]
They mention 100GeV/m gradients in the paper. If you could get that for 150m you'd have 15 TeV, comparable in energy to LHC (~14 TeV).

As I understand it, you can't just build a pipe and get the full gradient for X meters. Rather you build a (relatively) small device which has the 100GeV/m gradient, and then you'd glue many such devices back-to-back. So you get some overhead from the interconnects etc. Still, with 10x overhead it's "only" one mile.

The other point is that not all applications need TeV scale. For such applications maybe just a few stages would be sufficient. In which case it might be room-size or less.

SiempreViernes 373 days ago [-]
Further down someone posted the journal article[1] that describes a centimetre scale accelerator, that certainly counts as mini to me.

[1]: https://journals.aps.org/prab/abstract/10.1103/PhysRevAccelB...

jessriedel 373 days ago [-]
The research is about an hypothetical alternative acceleration method, not the one used at the LHC.
mrfusion 373 days ago [-]
I’m really curious about the spacecraft propulsion applications of this.
imglorp 372 days ago [-]
I was about to laugh at this commenter for watching too much Star Trek but decided to read a little. Turns out Robert Forward did some work on this and it's not so bad.


mrfusion 372 days ago [-]
Ion drives are just particle accelerators so why not?
swebs 373 days ago [-]
>Sorry, the page you are looking for cannot be found.

>It is possible this article may have been removed after being published.

I can't seem to find an archive either.

magicalhippo 373 days ago [-]
This is the paper the article was based on/linked to: https://journals.aps.org/prab/abstract/10.1103/PhysRevAccelB...

PDF is surprisingly freely available.

jessriedel 373 days ago [-]
It's true that many physics journals aren't open access, but essentially every paper written since 1992 is available on the arXiv, so not that big of restriction.

Incidentally, the full text of the article is available in HTML too, which might be easier on mobile.


magicalhippo 373 days ago [-]
Sure, just refreshing not having to go the extra step and find it on arXiv :)
Steuard 372 days ago [-]
I wonder if this is included in the SCOAP3 categories? (The vast majority of high-energy physics research is now open-access, due to collective negotiations between researchers, libraries, and publishers: https://scoap3.org/what-is-scoap3/ )
WorkLifeBalance 373 days ago [-]
Article has been removed?
patagonia 373 days ago [-]
Explain it to me like I’m 5 please?
HelloNurse 372 days ago [-]
Computer simulations (without actual experiments) of improved advanced techniques to produce a "shower" of electrons and positrons by hitting a metal target with a laser, which are then accelerated and confined with a second laser driving plasma waves.

The figures in the article, with lasers reflected by mirrors and particle beams going through the mirrors, suggest a very small but decently powerful single stage accelerator; using this technique as a building block for a large accelerrator isn't discussed.

fenk85 373 days ago [-]
There seems to be a push lately in UK media of running newstories about "making Britain Great again", just last week we had a story about a new spaceport, this week there is stories without source about EU caving in to all brexiteer demands and so on

All while the country is teetering on edge and could drag down its neighbours into another recession (selfmade this time), the NHS and local authorities remain in crisis, pound is weakening and inflation keeps going up.

It sucks being stuck sort of speak between 2 of your good neighbours undergoing a mental breakdown and self harming

dang 373 days ago [-]
This is way off topic and breaks the HN guidelines against taking threads into extraneous flamewars. Please review https://news.ycombinator.com/newsguidelines.html and follow the rules when posting here.

Edit: since you have been using HN primarily for political battle, we've banned the account. If you don't want to be banned, you're welcome to email hn@ycombinator.com and give us reason to believe that you'll follow the rules in the future.

Ntrails 373 days ago [-]
This isn't the "UK media", this is a university trying to sell itself as doing some cool research / coming up with ideas (which, incidentally, is their job).

If you really want to rant about the media spinning brexit lies then go ahead - you'll find plenty of willing listeners, but at least try and do it on a news story that actually fits your argument?

windows_tips 373 days ago [-]
What does this have to do with the article?
abainbridge 373 days ago [-]
Not much, but I'd rather hear the pros and cons of Brexit discussed here than on most of the rest of the internet. At least here there are some clever people and the moderating system works well.
swebs 373 days ago [-]
There's plenty of discussion on articles discussing Brexit. It's not really related to particle accelerators.


piokoch 373 days ago [-]
I would say there is push lately to picture UK situation in very black colors and I believe many of those claims are not really justified.

Firstly, inflation is not going up, at least I couldn't find any evidence of that.

Secondly, looking at the UK trade partners (for instance here http://www.worldstopexports.com/united-kingdoms-top-import-p...) I see that UK has trade deficit will all EU countries, given the fact that UK has well develop economy they can in fact gain on leaving UK and relaying on bilateral deals (and I guess those who are bashing UK most will be first in the queue to start trading with them - Germany approach to Nord Stream that can be potentially dangerous for EU energy safety shows that when it comes to money, EU "unity" is thrown away quickly).

Third, weakening pound is actually good for UK, the goods they produce are cheaper, so event if imported goods are more expensive at some point this will come to equilibrium.

Fourth, UK has still hidden gems like tax havens here and there, including the one at the very center of London - quite convenient for all the rich people who, accidentally, have also a lot of political power and surely they would not like UK to be hurt too much.

The only danger I see is that Scotland might try to gain independence and walk away with the oil taken from the North See, this would shrink UK domestic market and could indeed do some harm.

simonh 373 days ago [-]
>I see that UK has trade deficit will all EU countries... they can in fact gain on leaving...

This is an absurd fantasy. If trade deficits on their own made you poorer, the UK and US would have been reduced to third world status decades ago. The Uk has very low unemployment, there just isn't a free labour pool available to move into manufacturing. Hands up anyone from the UK here who wants to give up their job to go on to a production line, or wants that for their children? Forcing people out of better paid more valuable jobs into low end manufacturing, driving up costs for UK consumers, to serve some mercantilist daydream won't make the UK any richer.

Chris2048 373 days ago [-]
> there just isn't a free labour pool available to move into manufacturing

Does the government care about manufacturing? They closed the mines and moved towards a "service economy" last I heard..

> who wants to give up their job to go on to a production line, or wants that for their children? Forcing people out of better paid more valuable jobs into

There are northern towns that would love those jobs. Their children are currently at lidl checkout counters and behind pub bars.

simonh 371 days ago [-]
So we’re going to close all the Lidls and pubs? You’re not making any sense. By definition those people are already employed and whatever happened in manufacturing or any other sector, those jobs would still need to be done.
Chris2048 371 days ago [-]
Maybe those jobs would pay more if there weren't 4 people applying to each role - enough to buy more options.
lawlessone 373 days ago [-]
>The only danger I see is that Scotland might try to gain independence

Hey , Ireland here, you're completely ignoring cutting our island in two again which will very likely lead to a resurgence of the IRA.

>Third, weakening pound is actually good for UK, the goods they produce are cheaper, so event if imported goods are more expensive at some point this will come to equilibrium.

Yeah and the young generation brexitors have screwed over will be old by then.

matthewmorgan 373 days ago [-]
Look out for a resurgence of paratroopers then
TheOtherHobbes 373 days ago [-]
Firstly inflation is still over the 2% target and shows no sign of coming down - an entirely self-inflicted own goal caused by the post-Brexit drop in Sterling.

Secondly, the UK is primarily a service economy, and Brexit will devastate large swathes of the service industries.

Third, this is a standard talking point, and is unsupported by facts - one reason (there are others) being that increased import costs for physical goods from tariffs and a declining currency balance out any possible gain from extra income.

Fourth - I don't think trying to turn tax avoidance into the UK's primary economic activity is a terribly good idea. You may disagree, of course.

Scotland will indeed walk away. Ireland will... change. Gibraltar will turn into even more of a mess than it is now.

And so on.

There is in reality absolutely no upside to Brexit. Except for traders shorting the pound, there are no non-imaginary opportunities - only massive costs and disruptions.

And propaganda and PR won't change that. There's certainly been an uptick in British flag waving in the UK, but it takes more than that to run a modern economy.

The irony being that Brexit will destroy the industries the UK is a world-class player in - financial services, law, tech research, engineering, science research, and the arts.

kabouseng 373 days ago [-]
"Oceania has always been at war with Eurasia."

Sorry your comment just really made me think about the book 1984.

mbroncano 373 days ago [-]
I’ve had the same impression as of late. Alas, in a very English fashion, please be advised we don’t talk about those things in public, as you should know already. Same for racism, bigotry, xenophobia and the rest of virtues our great country is well known for.
JulianMorrison 373 days ago [-]
Could you get it in a handgun form factor? Asking for a friend.
grpaceloidsop 372 days ago [-]
Can anyone explain why using antielectrons instead of electrons means the accelerator can be made smaller ?