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.

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Engravings in “Wandering the Immeasurable” sculpture outside the CERN globe?

Does anyone have a PDF or a file that shows all of the engravings on the "Wandering the Immeasurable" sculpture by Gayle Hermick outside of the CERN globe of science and initiative?
5
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40 views

What's the next big goal of the Large Hadron Collider?

Obviously, physics lovers everywhere were excited at the announcement that the LHC had verified the existence of the Higgs Boson. As a non-physicist, I like to keep up with what I can regarding the ...
4
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103 views
+100

Statistical significance in Z boson excess paper

In a recent ATLAS paper, a excess of $3\sigma$ was reported from the Standard Model prediction in a search looking for a same-sign dilepton signal with an invariant mass around the Z peak. For brevity ...
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LHC: Irreproducible results: when/where else have we put so much trust in one test facility? [on hold]

After I watched "Particle Fever"--the movie about Large Hadron Collider (LHC) and the successful identification of the Higgs boson--I became a bit concerned with that team's handling of various ...
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0answers
56 views

Nature of particle spectra at ALICE

I have a question regarding the nature of the particle spectrum at ALICE as a function of momentum. The spectra in question can be seen here. My question is, why is it that the particle spectrum in ...
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29 views

How can I choose my desired direction in which the electrons travel?

If I take a circular vacuum tube (like a particle accelerator) and try to accelerate the electrons in it with a bunch of magnets and like charged panels to repel or attract the electron in it and ...
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3answers
214 views

Fiducial volume in collider/detector physics

I'm trying to make some sense of ATLAS measurements for a personal project to learn how to use Pythia, and part of my work requires me to recreate the distribution for Z boson decay. I encountered the ...
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3answers
333 views

What would happen to me if I was in the LHC while it was running? [duplicate]

This is possibly a stupid question, but one I have been always wondering. What would happen to me if I was in the center of the Large hadron Collider while it was running? Would the energy of the beam ...
6
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1answer
68 views

What is the temperature of an LHC Bunch?

From various places, I've found that an LHC bunch seems to be about 100mm long, 0.1mm wide, and contains about $10^{11}$ protons or anti-protons. The de Broglie wavelength is about $10^{-18}$ meters, ...
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1answer
30 views

Hard processes in particle collisions

This is in reference to a MC generator called Pythia, but has wider applicability because the phrases are used widely in particle phyiscs, even though I have not managed to find a clear, ...
6
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2answers
66 views

Why must energy be increased in a cyclotron to refine measured distance?

I have been listening to Nima Arkani-Hamed's messenger lectures at Cornell, and was confused by one point. He says that in order to measure at increasingly small distances energy must be increased (he ...
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1answer
63 views

How experimentalists put bounds on new physics at the LHC?

I would like to understand how experimentalists search for new physics at the LHC. Lets imagine I want to use the LHC data to put a bound on the coupling of some new physics effective operator, say, ...
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91 views

How possible is it that the Large Hadron Collider (LHC) on its second try, could disrupt the gravity of Earth?

How possible is it that the Large Hadron Collider, on its second try, could disrupt the gravity of Earth?
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65 views

Why is the energy of particles in accelerators much higher than the energy of the particles they are trying to find?

I have been wondering. In the LHC, or other particle accelerators for that matter, they are colliding particles with energies above TeV. The LHC is going to be 14 TeV or something like that the next ...
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0answers
22 views

Where can we find LHC results talks online?

I'm looking to educate myself on some searches at the LHC, but I find it easier to understand what's going on if I watch a LHC results talk (e.g. by ATLAS, CMS, or an overall summary by a theorist) ...
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68 views

Hadron Supercollider - How does smashing protons reveal facts of the inception of our universe?

How does smashing protons at high velocity reveal how our universe was formed? At some point, wouldn't the atoms need to come together in order to form planets etc? I am a curious student- not a ...
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322 views

How detectors in particle colliders can differentiate neutrons from antineutrons?

Their mass is the same. None of them interacts with EM fields. And their decay (around 1000s) is far too slow to see their decay products yet in the detector. How is it then possible to differentiate ...
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140 views

Nuclear fusion using electromagnetic fields

I was just thinking about how deuterium and tritium are charged particles and so I couldn't help but wonder why we don't use the same process used in the LHC(electromagnetic fields to accelerate ...
2
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2answers
112 views

Where can I find the datasets from LHC?

I know that most of the datasets from ATLAS or other particle physics experiments are terabytes, but I was just curious is there any place where one can find them to download? And one more question, ...
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138 views

LHC data and mathematics of QFT

I'm reading Frederic's Paugam Towards the Mathematics of Quantum Field Theory, an advanced theoretical physics book. I would like to know how I could apply the theories in this book. For example, ...
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149 views

Can the Large Hadron Collider break the speed of light? [closed]

Can Large Hadron Collider experiments break the speed of light at some point in the future?
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3answers
236 views

What are the main algorithms the LHC particle detectors use to reconstruct decay pathways?

I am just starting to look into how we understand the data from particle collisions. My question is, what are the algorithms or ways that these detectors interpret the data? Are there standard ...
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1answer
82 views

Has the possibility of Higgs boson being a composite particle excluded already?

I heard some theory, such as technicolor, predicts the Higgs-like particle discovered at LHC should be a composite particle (correct me if I am wrong). Has this possible been completely excluded ...
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3answers
100 views

Why do physicists use LHC?

My question is why are we colliding particles in LHC to produce new ones? And these particles that they sometimes say live for a fraction of a second, how in space they exists then? In space all ...
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2answers
95 views

For what rare events was the LHC built?

I understand that for low cross-section events a very high luminosity is necessary in order to obtain enough data to produce meaningful statistics. That is why the LHC was built. But which are these ...
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844 views

Impostor Higgs?

I recently came across this article, published in the respectable European Physical Journal A. (Apparently, there isn't any corresponding arXiv article for this, so I'm sorry if everyone isn't able to ...
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1answer
85 views

Why can't we measure branching ratios of the Higgs at LHC?

There are theoretical predictions for SM Higgs decay branching ratios. What about the experimental results on BRs? All that I found was measurements of signal-strengths $\mu = \frac{(\sigma \cdot ...
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1answer
87 views

Different cross section for W and Z boson

At hadron colliders the cross section for W production is about ten times larger than the production cross section for Z bosons (e.g. Figure 2 in this review article). I guess the dominant ...
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1answer
125 views

What would happen if two entangled particles collided?

Does that is even possible? I have almost zero knowledge in quantum physics, it is just a curiosity that popped in my mind.
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170 views

Baryonic density in collision experiments

Does anyone know any way of estimating the net baryon density in collision experiments, e.g. in LHC, RHIC, or the upcoming ones at GSI-FAIR? I have comes across many hand-waving arguments, sample - ...
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1answer
49 views

Easy formula for ultrarelativistic bremsstrahlung?

I am very curious if an easy calculable formula for the bremstrahlung radiation of deeply relativistic, charged particles exists, if they are moving on circular orbit: $P(E,m_0,Q,r)=?$ ...where ...
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2answers
70 views

What were the maximal collision energy of the LHC if it were rewired to $e^{-}-e^{+}$ collisions?

Yes, I know, that it weren't a large hadron collider then. No, I don't think, that the creators of the LHC didn't know what they do. I am just curious. How could it be calculated? A such rewiring ...
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0answers
107 views

Jet rapidity vs. Pseudorapidity

thanks to this post Why is pseudorapidity defined as $-\log \tan \theta/2$ I got a better understanding of what makes (pseudo) rapidity an interesting an often-used concept. Tangentially working ...
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1answer
87 views

Reusing the bremsstrahlung energy in circular accelerators?

I think the Bremsstrahlung happens as a strong radiation emitted by the accelerated particle stream. As in this question is visible, it is the main cause of the energy loss in such big particle ...
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Why doesn't the LHC accelerate electrons?

Electrons have a much bigger charge density as the protons (and especially lead nuclei), aren't compound particles as the protons (and especially lead nuclei) are able to get a much bigger energy ...
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1answer
86 views

W + jets at NLO

I would like to calculate $pp \rightarrow W (\rightarrow \ell \nu)$ + n-jets (n=2, maybe also 3) at NLO, with some cuts and plot some distributions. I used MadGraph extensively for LO processes and I ...
6
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2answers
207 views

Could a tetraquark $q \bar{q} q \bar{q}$ be colorless?

CERN just posted this article where it informs that it was found an hadron which cannot be classified within the traditional quark model. What other models are there to explain this result? Or is it ...
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35 views

The Magnetic Field around the Proton Beams in the LHC

How would one most appropriately model the magnetic field around each bunch of protons in the LHC at maximum operating speed? Is the assumption of a wire of the same length of the beams (~30cm) with ...
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0answers
158 views

How far could the LHC “fire” a particle

Very simple question, and frankly quite a silly one, but I'm currently writing a lecture for secondary school kids and I'd love to tell them how far the Large Hadron Collider could fire a proton. The ...
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3answers
197 views

Are there any Meson colliders?

There are no stable mesons as far as I know. Are there any meson-colliders analogous to for example proton-proton colliders?
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35 views

References on the LHC experiments

I'm looking for a references / short book which discusses what is going on LHC collider - specific experiments, collision processes, analysis of data, how exactly the facility is operating (not ...
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1answer
149 views

Why 1 Month LHC Magnet Cooling Times

An often quoted figure is that the LHC magnets take a month to completely cool and a month to warm. There is never an explanation as to why that is. I can conjure any number of reasons (slow changes ...
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1answer
252 views

LHC Experiments for finding parallel universes?

I watched this video featuring Michio Kaku explaining parallel universes. In the last two minutes he said that experiments in the LHC could reveal that there might be parallel universes and then he ...
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79 views

How do they draw collision pictures in Atlas?

Is the picture below a simulation? How to they draw these pictures? The picture is from here.
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4answers
395 views

how long do large hadron collider experiments take?

This travel stackexchange answer has kinda got me wondering... how long do experiments involving the large hadron collider usually take? I'd expect you run it for a few seconds and bam - higgs boson ...
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2answers
111 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 ...
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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"?
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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 ...
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41 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 ...
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1answer
126 views

Can micro black holes form in the Sun?

Wikipedia writes to say ...