is appropriate for questions dealing with the physics of beams in accelerators (synchrotrons, cyclotrons, linacs, betatrons and other types of accelerators); the ways in which beams are generated; the accelerating, bending and focusing equipment; and the intrinsic limits that arise in trying to ...

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What physics does the Super Proton Proton Collider intend to explore in the $\lesssim 100\:\mathrm{TeV}$ range?

Chinese scientists have completed an initial conceptual design of a super giant particle collider which will be bigger and more powerful than any particle accelerator on Earth. With a circumference of ...
2
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0answers
73 views

Is muon muon annihilation already realised?

As muon colliders do not yet exist, has muon-muon annihilation already been realized experimentally?
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4answers
2k views

Do free-electron lasers actually lase?

Free-electron lasers are devices which use the motion of highly energetic electron beams to produce bright, coherent radiation in the x-ray regime. More specifically, they start with a high-energy ...
2
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1answer
39 views

How would the CLIC accelerator work?

After reading what I could find about the CLIC accelerator, I still don't understand how it would work. If someone could explain how the CLIC would work, I would greatly appreciate it.
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2answers
153 views

How many particles can a particle accelerator accelerate at once?

Does a particle accelerator lose its accelerating effectiveness as the number of particles being accelerated increases? According to Wikipedia, the mean acceleration of a proton in the Large Hadron ...
0
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0answers
31 views

Magnetic field of a circular particle accelerator

Suppose there's a $500 \ GeV$ proton beam ($q=1.6 \times 10^{-19} C$) inside a circular particle accelerator, what would be the magnetic field intensity $B$ in Teslas required to keep it stable at a ...
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1answer
42 views

Combined function magnet

I am searching how a combined function magnet for accelerator physics works, but on the books that i have and on the web i can find only patents for this thing, that suppose to know already how this ...
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0answers
28 views

Why can't electrostatically accelerated deuterium beams neutralized by electrons produce net energy fusion? [duplicate]

I was looking through the various nuclear fusion approaches and it struck me that they all suffered from one of two problems. Either they wasted a lot of energy trying to accelerate fusion fuel to the ...
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1answer
32 views

Can spin polarisation restrict the possible types of LHC proton-proton collisions?

Despite the massive luminosity at the LHC, it's probably correct to say that no two collisions are ever identical, even up to symmetry. Not only are there all possible impact parameters, but the ...
3
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1answer
75 views

How are the two proton beams at the LHC accelerated in opposite directions?

At the Large Hadron Collider (LHC), how are the protons in the two beams accelerated in opposite directions?
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1answer
29 views

5UDH Tandem electrostatic accelerator

What does UDH stands for in the name of an electrostatic accelerator 5UDH-2 Tandem accelerator? Does it is related to its working or just a trade mark?
9
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1answer
604 views

Do particle accelerators centrifuge the quarks of a proton?

Is it right that circular particle accelerators use magnetic fields to deflect the particle beam? Using the simple equation of "a charged particle in a magnetic field": ...
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2answers
47 views

Advantage of using higher luminosity accelerator

If two accelerators operate at the same energy but different luminosity, is the only advantage of accelerator with a higher luminosity that there will be more events in a given amount of time, thus it ...
3
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1answer
74 views

Why is an electrostatic accelerator so inefficient at converting wall power to beam power?

I was reading up on electrostatic particle accelerators when I read a statistic stating the efficiency of converting wall electrical power (the electrical power from the outlet) into beam power in an ...
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1answer
105 views

Why would an alpha-beryllium neutron source generating a radioisotope not produce controllable net power?

I have a question. I was looking through the table of nuclides and noticed that the energy needed to produce certain radioisotopes was less than the energy given off by the radioactive decay of that ...
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1answer
94 views

Using ion beam to create strong magnetic field

Consider, I want to make very strong magnetic field in some spot in space ( focus ) but I cannot put any solid material ( like metal conductor, or superconductor ) close to that spot (e.g. because ...
2
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1answer
60 views

Electron beam in magnetic field - increase or decrease the field?

When I fire an electron beam into homogenous magnetic field ( eg. inside Helmholtz coil ) it will bend into a circle => it will form a coil ( = current loop ) itself. The magnetic field created by ...
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1answer
74 views

Accelerate neutral particles

I know it is not possible to accelerate particles via the Lorentz force $F=q(E+v\times B)$, because $q=0$. However, the magnetic moment $\vec\mu$ for such a particle usually is $\neq 0$. Is there a ...
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1answer
57 views

How would one get the particle beam in Stern Gerlach experiment

How would I get a beam of silver atoms? I imagine this to be problematic, since the silver atoms are neutral. How would I accelerate them?
2
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1answer
61 views

How would one build an RF cavity?

How does an RF cavity, such as the RF cavities in the LHC, work mechanically and mathematically? How would one build an RF cavity? What equations govern the speed of a charged particle in an RF ...
6
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2answers
70 views

Does the Advanced Photon Source use electrons or positrons?

Synchrotron light sources like the Advanced Photon Source (APS) (as well as SPring-8 and the ESRF) are typically mentioned as accelerating electrons up to the GeV range to produce extremely high ...
2
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1answer
138 views

Why can't a high intensity beam be injected into the LHC when the machine is empty

Watching this YouTube video about the LHC at around 3 minutes and 50 seconds into the video the narrator says... For machine protection reasons we are not allowed to inject a high intensity beam ...
0
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1answer
57 views

How does an electron beam condenser work?

For example, a scanning electron microscope has multiple condensers that "focus" the beam into a smaller spot size. How does a condenser actually change the direction of electron flow in a non-uniform ...
2
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1answer
44 views

Beam excited RF cavity modes

When beam (bunch of electrons) transverse RF cavity, it will excite modes (resonant frequencies). The mode for steady state is quite well described, I am wondering is there any theory describe the ...
6
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1answer
142 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
58 views

Do accelerated particles change in size as they change in mass?

If a charged particle is accelerated to incredible energies in a particle collider, its mass increases. Does its radius increase as well and, if so, how does it compare to the change of mass? Could ...
0
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1answer
78 views

Why is the storage ring of a synchrotron a vacuum?

Why is the storage ring of a synchrotron a vacuum? I know that when the accelerated particles get to the storage ring they lose energy, releasing synchrotron radiation, but how does the vacuum make ...
6
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2answers
436 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 ...
2
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2answers
77 views

Meaning of SIS in accelerators

With reference to accelerator facilities, the term "SIS" is often used. e.g. SIS-100, SIS-300 etc. What does SIS stand for, in this context? (The last S is probably for Synchrotron) Google appears ...
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1answer
96 views

How does the number of events per bunch collision scale (as function of energy, luminosity …)

Looking at Table 1 of Burton Richter's recent article High Energy Colliding Beams; What Is Their Future? I'm wondering how the number of events per bunch collision ("$N_b$") scales for the collider ...
3
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1answer
126 views

Is “microbunching” in a free electron laser limited by the Pauli exclusion principle?

As I understand it, a free electron laser can basically be pictured as a synchrotron light source with an undulator which by the particular setup causes the electrons to self-attune so that they ...
2
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3answers
206 views

Can lightly-ionized atoms be accelerated to relativistic speeds with current technology?

I know there're lots of various particle accelerators, which can accelerate particles to TeV's of energy, but it seems they all work on electrons or nuclei or other elementary of tightly-bound ...
0
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2answers
140 views

Electron energy in a synchrotron storage ring vs. X-ray energy from the wiggler: why is the latter much lower?

I know in large synchrotron facilities some beamlines produce very intense X-rays by injecting the accelerated electrons into "wigglers". I have read that the typical energy of the electrons in the ...
2
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1answer
50 views

What technological advance would allow LEP3 to surpass LEP2?

I learned that for electron accelerators synchrotron radiation and acceleration are the limiting factors. This article, that I found in one answer to this question mentions that one would not use the ...
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1answer
119 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 ...
18
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4answers
3k views

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 ...
3
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1answer
193 views

Why did it take a long time to discover top quark?

In high school physics, I learned that it took a long time before the top quark was discovered. One of the reasons that was given in my book was that the top quark has a large mass, much larger than ...
9
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3answers
2k views

Do particle accelerators produce (dangerous) radiation?

I was under the impression that particle accelerators were pretty harmless, but some article said that they produce harmful radiation when you're in the tunnel. Given that the Internet... isn't always ...
5
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3answers
476 views

Why doesn't an electron feel an electric field, and thus accelerate whilst inside the drift tube of a linear accelerator?

Why is the resultant field strength inside the tubes of a linear particle accelerator zero (i.e. the particles move in constant velocity through the tube)? As in the diagram, the particle ...
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2answers
204 views

Are there moments in particle collision experiments where the particle beam is in open air?

I keep encountering the story of Anatoli Bugorski, who apparently got hit in the head by a proton beam at the U-70 PS in Protvino, Russia. I find it difficult to believe that this is actually ...
1
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6answers
263 views

Do the particles made in a collider exist outside the collider?

Below is the transcript of a section from Demystifying the Higgs Boson with Leonard Susskind. Around 1:02:23 Susskind says that the heaviest of the fermions is called the top quark. Top quark is ...
0
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1answer
256 views

How does a synchroton work?

I know that a linear accelerator (linac) works by having terminals that get longer progressively and changes polarity due to AC current. And I also know that a cyclotron works by having two ...
5
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1answer
343 views

What are the strongest sources of collimated neutrons and protons?

I am imagining an unusual experiment which will require intense beams of either protons or neutrons. The experiment would work better with neutrons, but neutron sources are much weaker messier so I ...
1
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0answers
90 views

How do I build an alpha emitter?

I would like to build an alpha emitter. I suppose I had some vague idea of knocking the electrons off of some helium. But upon further examination the idea does strike me as...naive? My question is ...
3
votes
1answer
49 views

What would happen if the electric field was cut to a cyclotron half-way?

After accelerating say a proton, half way, if the alternating electric field was cut, would the proton maintain a perpetual circular motion at the same radius? I know that any charged particle moving ...
2
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1answer
310 views

At CERN - What do you call the moment (event) particles crash together in the particle accelerator? [closed]

At CERN - What do you call the moment (event) particles crash together in the particle accelerator? At CERN they crash different particles together and measure what comes out. What is the name of the ...
0
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1answer
154 views

LINAC: why are they being accelerated?

I have read the wiki page and I have seen this image, but I still don't understand why they are being accelerated. Could you easily explain it to me? Thanks a lot
2
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1answer
81 views

Creating a stream of single file atoms

How do you go about creating a stream of single file atoms? The aim is to fire a stream of single file atoms (hydrogen, helium) down a vacuum and detect there arrival on the opposite end. Any ...
1
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2answers
733 views

Muon production in particle accelerator

PAMELA is a particle accelerator which have two concentric rings, protons are accelerated in the inside ring. At ISIS muons are produced when a 800 MeV proton beam collides with a graphite ...
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2answers
2k views

What exactly is the difference between a sychrotron light source and a free electron laser?

Cyclotron radiation is radiation emitted by a charged particle being bent by a magnetic field. The only difference between cyclotron and synchrotron radiation is that the latter occurs at relativistic ...