World's largest particle accelerator built by the CERN (European Organization for Nuclear Research) near the Franco-Swiss frontier near Geneva, Switzerland. It is designed to collide beams of protons of up to 7 TeV. It contains the important detectors ALICE, ATLAS, CMS and LHCb.

learn more… | top users | synonyms (1)

6
votes
2answers
112 views

Deciding what to collide at particle accelerator

Different particle accelerators use different types of collisions. For instance at the LHC they investigated p Pb collisions while its predecessor (LEP), used to collide electrons with proton and at ...
0
votes
0answers
31 views

what does “medium-induced gluon radiation” mean

I've often run across phrases such as "medium-induced gluon radiation" from some papers,what is "medium-induced gluon radiation"?
0
votes
3answers
1k views

The LHC - Proton Speed Limit [duplicate]

I'm originally from stack overflow, so this is my first foray into this particular community. I've read in numerous places that the Large Hadron Collider is capable of accelerating protons at ...
0
votes
0answers
43 views

Why don't photons crash into each other occasionally? Or do they? [duplicate]

At the LHC, researchers smash particles into each other at speeds close to speed of light. Photons, on the other hand, already move at the speed of light. Do they ever smash into each other? Or do ...
2
votes
1answer
128 views

Can micro black holes form in the Sun?

Wikipedia writes to say ...
0
votes
1answer
377 views

The future of supersymmetry [duplicate]

Considering the fault of any experimental evidence from LHC for supporting the supersymmetry idea until now, can we say that it is dead? Generally the people who are working on this subject say that ...
0
votes
2answers
205 views

Achieving almost the speed of light

I am much interested in physics. I have been caught up with one serious question related to speed of light. Hearing about Large Hadron Collider (LHC), it is said that protons in there are accelerated ...
1
vote
3answers
100 views

Predicting the mass of the Higgs particle

Physicists in Europe said that only after combining data collected at a laboratory in Switzerland with data collected at a laboratory in the U.S, were they finally able to announce the discovery of a ...
2
votes
2answers
317 views

Why is the Higgs boson created so infrequently at the CERN collider?

Although each collision at CERN has the available energy to create a Higgs boson each time, the vast majority of the time it does not create one. I suspect that part of the reason for this is that ...
0
votes
3answers
492 views

LHC vacuum tube diameter [closed]

What's the diameter of the tube where the protons fly around? I dont mean the overall diameter (~1-10 m), instead the inner most ultra-high vacuum tube where the protons are. The inner pipe, the ...
0
votes
1answer
127 views

how do they rip one single atom from something?

this is simple. what i actually want to ask is, when they do the subatomic particle collision experiments, how do they produce one single subatomic particle, e.g proton, neutron? how do they rip one ...
2
votes
4answers
370 views

SUSY and the Large hadron collider

Did the LHC rule out SUSY as a solution to the hierarchy problem ? What's the common belief among theorists regarding the possibility of discovering SUSY in the 2015 run of the LHC ? Did the absence ...
1
vote
2answers
191 views

How does the Cern LHC collide particles head on if uncertainty principle limits the precision

I have been wondering why doesn't the uncertainty principle prevent the LHC experiment as if one want to collide two particles together one must accelerate a particle to certain speed and aim it at ...
0
votes
0answers
50 views

Can TOTEM's T2 detector measure differential cross sections?

My current research involves making a prediction for data collected by the TOTEM experiment at the LHC. The experiment is primarily designed to measure the total inelastic and elastic scattering cross ...
28
votes
5answers
2k views

Is a proton collision (collisions like in the LHC) visible to the human eye?

I was curious if a proton collision is visible to the human eye. (This might sound like a really basic question and forgive me if it is. I am very inexperienced in Physics and just wanted an answer ...
3
votes
1answer
119 views

What is the $t\bar{t}$ production supposed to bring up

The $t\bar{t}$ production, I've read, that will somehow confirm the QCD and might bring up new physics. Why are we studying $t\bar{t}$ production from $p-p$ collisions at the LHC? What are we trying ...
2
votes
0answers
41 views

Limits on stable charged particles

Are there generic model-independent limits on massive stable charged particles (say 10-500GeV)? I mean SU(2)/color singlets with just a hypercharge. For example the LEP search (CERN-EP/99-075) was ...
1
vote
2answers
275 views

If you could look at the LHC beam, what would you see?

Kind of a weird question compared to what I normally ask on here, but I've been wondering about this for a while. Does the LHC beam generate any photons within the visible light spectrum? Assuming ...
3
votes
1answer
131 views

Convolving Parton Distribution Functions

I have the cross-sections as a function of $\sqrt{s}$ for a process with a $u$-quark and $u$-antiquark in the initial state (eg.: $u \bar{u} \to e^- e^+$). I have a standard parton distribution ...
5
votes
2answers
117 views

Do the proton PDFs change much with Q?

Specifically, the second moments, do they change much from say 100 to 1000 GeV? Why or why not?
2
votes
0answers
92 views

What are the implications if Supersting theory is discredited? [duplicate]

Please forgive my ignorance, I am not a student of physics in any capacity, therefor my understanding of string theory is extremely limited to say the least. Based on the recent lack of evidence in ...
23
votes
3answers
23k views

What is the current status of string theory (2013)?

I've seen a bunch of articles talking about how new findings from the LHC seem to disprove (super)string theory and/or supersymmetry, or at least force physicists to reformulate them and change ...
15
votes
6answers
3k views

What would happen if Large Hadron Collider would collide electrons?

After some reading about the Large Hadron Collider and it's very impressive instruments to detect and investigate the collision results, there is a remaining question. What would happen if the ...
5
votes
1answer
308 views

How much does a proton weigh when it is going around the LHC at CERN?

Considering that speed increases weight and the proton is going at almost the speed of light, I would like to know how much a speeding proton would weigh in the LHC.
11
votes
2answers
231 views

What is the 'bump' near $M_{\mu\mu}\approx 30\text{ GeV}$

In this (attached) Summer 2011 plot from CMS (twiki page), they have a plot of the dimuon invariant mass spectrum across 3 orders of magnitude in energy. There seems to be a 'bump' near ...
2
votes
1answer
231 views

Impact of LHC on other science and technologies, in particular on mathematics?

The Large Hadron Collider (LHC) "remains one of the largest and most complex experimental facilities ever built" (Wikipedia); it may even be the most complex project in humankind's history (?). Such ...
4
votes
2answers
279 views

Assuming that extra dimensions will not be visible at LHC, what motivation will still remain to study them?

Many physicists believe that there is little possibility of observing extra dimensions at LHC so that some extra dimension models originally designed to solve hierarchy problem (ADD/Randall-Sundrum) ...
4
votes
1answer
145 views

Will Randall-Sundrum extra dimension scenario become defunct if not supported by LHC?

The Randall-Sundrum extra dimension scenario had been one of the most extensively studied class of theories. This offered a solution to the hierarchy problem. However, if this picture is not supported ...
9
votes
1answer
243 views

Which SUSY models are affected by the recent LHCb result?

The LHCb has recently published the observation of $B_s \rightarrow \mu^+ \mu^-$ with a branching ratio that agrees with the Standard Model (SM). There are many blog posts about it (See: Of Particular ...
2
votes
2answers
684 views

What would happen to a person that was inside the Large Hadron Collider when it is turned on? [duplicate]

Possible Duplicate: What would happen if you put your hand in front of the 7 TeV beam at LHC? Not a terribly scientific question, but one that I'm sure many people have thought about :)
10
votes
1answer
460 views

What does the latest $B_s^0\rightarrow \mu^+\mu^-$ results mean for SUSY?

A paper from the LHCb collaboration just came out last week, stating basically that the $B_s^0\rightarrow\mu^+\mu^-$ decay matches standard model predictions, and people are already shouting that SUSY ...
4
votes
2answers
2k views

Could we use particle colliders as fusion generators?

So I know the basic gist is that fusion power's main issue is sustaining the fusion. I also know that there are two methods. The Torus method and the laser method. The torus magnetically contains ...
3
votes
2answers
687 views

Missing transverse energy, exact definition

This might seem basic, but it is a bit confusing. You hear about missing transverse energy a lot in SUSY searches due to the LSP which cannot be detected. Let's say I have the 4-vector for the LSP. ...
0
votes
2answers
471 views

Are there experiments that are banned from being done at the LHC?

Are there experiments that are banned from being done at the LHC because they are too dangerous?
5
votes
6answers
377 views

Why not using cosmic rays to study HEP, since they are way more energetic than LHC?

Cosmic rays energies can exceed $10^{8}$ TeV, way higher than the energy scale achieved in the LHC or that can be achieved in the near future. cannot we just use them to study fundamental ...
1
vote
0answers
659 views

What is the relationship between Luminosity, Intensity, and Flux?

I am always confused by the terminology: In high energy particle scattering, and in particular, in the context of collider physics, what is the relationship between luminosity, intensity and flux? ...
2
votes
2answers
386 views

Some very basic questions on the Higgs Boson

What exactly is a boson? Is the Higgs boson the cause of gravity or a result of it? Does the collision of particles at the LHC create a gravity field or waves or somehow interact with the gravity ...
4
votes
2answers
174 views

Shouldn't LHC have used $p\bar{p}$ collisions, instead of $pp$ collisions, to study baryogenesis?

Baryogenesis is the physical process(es) that produced baryon antibaryon asymmetry in the early universe. That means, the laws that governed the bigbang was baryon-antibaryon symmetric. On the other ...
2
votes
1answer
93 views

random triggers

I understand that a small proportion of events at the LHC that would not trigger on any deterministic trigger are saved on what might be called a random trigger, so that, amongst other uses, proposed ...
2
votes
1answer
1k views

What's next after Higgs Boson discovery? [duplicate]

Possible Duplicate: Practical matter of the Higgs-Mechanism As everybody knows that the Higgs Boson was discovered on July 4th,2012, I am so curious about it. What are the possible ...
8
votes
1answer
327 views

What if the 126 GeV particle found at LHC that LOOKS like the Higgs is actually not the Higgs Boson?

I am suspicious of the Higgs announcement. Press mania aside, the scientists seem careful to say only that "we've found something which looks like the Higgs Boson". The difference between ...
6
votes
2answers
278 views

What will be the goal of (V)LHC after receiving upgrades?

If I understood correctly, the LHC will be shut down at the end of 2012 to prepare for the full-power, 14 TeV collisions in 2014. I also remember reading about a proposed luminosity upgrade some time ...
1
vote
1answer
134 views

Do protons in the beam on LHC interact with photons?

Do protons in the beam on LHC interact with photons? I wonder how a beam would look from outside. Is there a photo of a proton beam?
0
votes
2answers
182 views

From where this number of 14 Tev has arised for proton-proton head on collision in LHC?

I am interested in finding out, why are collisions at 14TeV done in the LHC, instead of some other energy?
1
vote
1answer
99 views

The Large Hadron Collider produce material residues?

In the LHC particles are accelerated until they collide, producing energy and this make new particles. My question is what happened after this. What happened to new particles and to old particles ...
2
votes
2answers
214 views

Batting averages of the Large Hadron Collider

As I understand it, the Large Hadron Collider's function is to throw particles into each other while avoiding hitting the nucleus? If quantum mechanics dictate the position of a particle can only ...
3
votes
1answer
123 views

Sources for new experimental limits on susy models?

I know the LHC people are publishing new limits every now and then, but as a non-expert in reading experimental papers (yet), I was wondering if there's a friendly website that collects and presents ...
4
votes
1answer
144 views

Are old fashion photomultipliers used in LHC experiments?

Are any photomultipliers used in any of LHC detectors? Or are only semiconductor devices used? If yes, then where?
10
votes
3answers
454 views

How do they handle energy in magnets at LHC?

I'm guessing that when the LHC ramps up to 4000 GeV this means they are increasing the current in the superconducting magnets as RF fields accelerate the beams. Where does this current go when they ...
4
votes
2answers
742 views

Can black holes be created on a miniature scale?

A black hole is so powerful to suck everything into itself. So is it possible that mini black holes can be created? If not then we could have actively disproved the rumors spread during LHC ...