Questions tagged [accelerator-physics]
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 manipulate beams. DO NOT USE THIS TAG for questions that concern the use of the particle beams once they arrive in the experimental hall.
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Efficiency of particle accelerators
Say the SLAC linear accelerator, to perform inelastic scattering, wants to fire an electron accelerated to 0.99c the speed of light at targets of atomic nuclei.
After the collision, the resulting ...
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As the speed time graph for a body thrown vertically upwards is not differentiable at the top point so why acc. is taken as 9.8 m/s² at the top point?
In the shown speed - time graph for a body thrown vertically up there is a sharp kink in the graph at the instant for which body is at highest position ie not differentiable so we can't find ...
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Why are accelerator beam neutrino experiments built an angle off the beam direction?
Was reading some papers and review articles on accelerator based neutrino experiments and this came up a few times. Most of what I could find mentions "shrinkage in neutrino energy spectra" ...
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Derivation of beta-beat in S.Y. Lee's Accelerator Physics
I'm following S.Y. Lee's Accelerator Physics (Fourth Edition), specifically Chapter 2 Transverse Motion, III.4 Quadrupole Field (Gradient) Errors. In paragraph (B) the beta-beat is derived in the ...
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Recommendation for a source on particle detectors
I am looking for suggestions on a particle detectors book. I have average knowledge in high energy physics and nuclear physics.
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Where does the databases for isotope fingerprints (such as those used in gamma specs) come from?
Using a gamma spec for example, compares energy data and intensity, against known databases to try to find a match, and uses this to identify the isotopes detected.
What data are these databases built ...
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What makes an ion source high brightness?
The spectral brightness of an ion beam is defined as $$βs = \frac{I_Ω}{d_v \times ΔE}$$ where $I_Ω$ is the angular current density, $dᵥ$ is the virtual source, and $ΔE$ is the energy spread. But how ...
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Partially circular and partially linear particle accelerators
I know that circular accelerators, due to the radiation emitted by accelerated particles, are limited by their size in what energies they can reach. Linear accelerators (linacs) instead could reach ...
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About Direct Laser Acceleration
How does this Lawson–Woodward theorem work. I read on the wiki that the particles cannot be accelerated by lasers. But I do see acceleration of electrons with free space. I wonder how this is done.
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Exciting the Plasma Wake Field in Other Ways
Is there any way to excite the wakefield in wakefield accelerators other than lasers and particle beams.
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Plasma recovery at wakefield accelerators
It seems that the current design requires filling the accelerator channel with dielectric plasma before use. Is there any way to quickly recover and quickly fill the dielectric plasma in the ...
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Can we use the concept of a railgun or coilgun to design a small particle accelerator?
A railgun is used as a linear particle accelerator to project projectile at high speeds. Why not use this concept to build a circular rail particle accelerator. A conventional railgun uses extremely ...
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Is mass spectrometry convenient to separate elements in a mixture?
Are particle accelerators coupled to spectrometers ever used to separate and extract different components of a mixture? If so, how much substance can be treated per day in this way? Would it be a ...
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On the optical properties of quadrupolar magnets
Here's the magnetic field produced by a quadrupole
Citing from Barr, Giles; Devenish, Robin; Walczak, Roman; Weidberg, Tony Particle Physics in the LHC Era (Oxford Master Series in Physics) (p.55,56). ...
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On the analogy between RF cavities and parallel RLC circuits
Every superconductive radio-frequency cavity can be seen as a parallel RLC circuit, as shown in the picture below:
The thing is every parallel RLC circuit acts like a band-stop filter: at the ...
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On slip factor and phase transitions in particle accelerators
In a uniform magnetic field $B$, a particle with mass $m$, charge $q$ and initial velocity $v$, undergoes a centripetal force (Lorentz force) which makes it travel on a circular orbit, with angular ...
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How can a neutral atom, e.g., a rubidium atom, be accelerated to a high speed? [closed]
I have this question because I am studying quantum friction for my PhD project.
Quantum friction could refer to the frictional force induced by the electromagnetic field fluctuations on a neutral ...
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In a synchrotron, do the charged particles within the beam lose mass (or another type of energy) after radiation has been produced?
I've been researching accelerators and synchrotrons and am a bit confused on what happens to the particles within the storage ring once radiation has been produced.
Do they keep circling the ring, do ...
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Accelerator physics text
Physicist here, looking for a suggestion for a very comprehensive, very detailed textbook on accelerator physics---particularly with a focus on cyclotrons/synchocyclotrons/AVF-cyclotrons. My work is ...
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What happens in a particle accelerator? [closed]
How is the particle accelerated? Is it by increasing its energy?
Is it only charged elementary particles that can be accelerated, because they are the only ones that can absorb photons and gain energy?...
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In simple English what is meant by "tagging", "triggering", "selection criteria" and "reconstructed events/particles/masses" in particle physics? [closed]
I am currently reading the original Higgs boson discovery paper, "Observation of a new boson at a mass of $125$ GeV with the CMS experiment at the LHC", HIG-12-028, which can be found ...
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On RF cavities in circular accelerators
Radiofequency pillbox-like cavities are used to accelerate particles, as shown here. They act grossly speaking like a LC circuit, so they are designed to work with a specific frequency.
This already ...
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Why does a magnet arranged in a magnetic accelerator propogate a wheel forward?
My question is related to an interesting video i saw on magnets. The link of the video is here https://youtu.be/iyv9GhaITNE , in this video at 1:52 of the video we see the wheel is moved forward but i ...
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Fission is to Cyclotrons as Fusion is to _________?
Using a cyclotron we can trigger fission in a controlled way.
My question is similar to cyclotrons, do we have a mechanism in which we can trigger fusion from a physics (non-chemistry) perspective ...
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Does an einzel lens draw current?
I was trying to think about the physics of a single particle in an Einzel lens. As it enters the lens, it would draw negative current, and then as it leaves the lens, it would draw positive current. ...
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Has there been an experiment with entangled particles to observe effect on decay time when one is at relativistic speed? [closed]
Has there been an experiment with entangled particles, two of the same, for example two neutrons, where one is left mostly at rest and the other accelerated to relativistic speed to observe if any ...
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Relativistic motion in particle accelerator
This question is attempting to simulate the process of a circular particle accelerator. We are given a constant electric field $E$ along the angular direction and a varying magnetic field $B$ along ...
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Molecular accelerators
I wanted to know if we have accelerators for molecules just like particle accelerators. If so, what are they called and what is the maximum size of the molecules that can be accelerated in such ...
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Does a low-gain free electron laser (FEL) emit coherent radiation?
For the low-gain free electron laser (FEL), an external field is injected into an undulator alongside an electron bunch. Due to phase slippage (because the light is faster than the electrons) the ...
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How long does the LHC take to accellerate a particle to its full speed? How long would a linear accellerator have to be to reach the same energies?
I'm wondering how long it takes the LHC to accelerate particles from rest to their top speed at 6.5 TeV. And related, how long a hypothetical linear accelerator would have to be to accelerate ...
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How can i shoot accelerated electron directly into the air?
I am trying to do an experiment in which I have to first accelerate the electron to 10eV and then shoot into the air directly. I need some kind of membrane which allows electron to pass
and keep ...
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How does a booster work in a particle accelerator like the LHC?
In the proton synchrotron booster (PS) booster at the LHC, protons are accelerated from $50 \, \text{MeV}$ to about $1.4 \,\text{ GeV}$. This takes about a second to accomplish. Since the radius of ...
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How do we derive the components of the magnetic vector potential from a known magnetic field?
The magnetic field is
$\vec{B}(r,\theta)=B_{0} \cdot[1+\mu(r)] \cdot [1+f(r,\theta)]\hat{e}_{z}$
where $f(r, \theta)=\sum_{n}\left[a_{n}(r) \cos n \theta+b_{n}(r) \sin n \theta\right]$, and $\mu(r)$ ...
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Can muons be used to reach the island of stability of superheavy elements?
While reading about the island of stability of superheavy elements[0], experimental approaches and related difficulties[1], an idea has formed in my head. Since I cannot find considerations of such ...
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Why can the neutron not be measured in this fixed-target experiment?
Consider a fixed-target-experiment, where negatively charged pions are shot at protons (the latter being at rest). The kinetic energy of the pions shall be known. One possible reaction is
$$
\pi^- + p ...
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Why are edge fields in undolators necessary to comply with Maxwell?
In our lecture scripts there is a paragraph about the magnetic field of an undulator:
"Its [the undulators] magentic field can be described by
\begin{equation}
\vec{B}\equiv-B_0 \begin{pmatrix} ...
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Can neutrons be manipulated with magnetic fields? Can neutron particle accelerators be built?
Neutrons have no electric charge and do not respond to electric fields as in a conventional particle accelerator. However, they are magnetic and do have a small magnetic dipole moment. So it should ...
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In a synchrotron, do electrons make periodic recoils?
Synchrotron radiation happens because circular motion of electrons produce a tangential acceleration-- or something along those lines.
Point is, photons are produced by these accelerated electrons.
As ...
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Radiation in particle accelerators
I was reading about particle accelerators in Wikipedia and I came across this.
Depending on the energy and the particle being accelerated, circular accelerators suffer a disadvantage in that the ...
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Using something like a linear accelerator, could a visible object to accelerated to thousands of miles per second?
I am wondering what problems would arise using the same process that accelerates protons, etc. on something as large as a bb or maybe just a grain of sand. Not sure the practical reason for this but ...
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How many atoms does a relativistic ion dislodge?
Given a large chunk of some hard, refractory material e.g. graphite, diamond, tungsten, at low temperature surrounded by vacuum, and an impacting relativistic ion – to be specific, say an alpha ...
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Electron gun voltages
I saw on the internet that catode of electoron gun should have negative potential to zero (ground). On the other hand catodes of tv CRTs were grounded and anodes were connented to positive high ...
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What is meant by spatial resolution in a particle detector?
I'm reading a document about a particle physics detector and its sub-detectors.
They mention that: ' its drift chamber has a spatial resolution of 130 μm'.
Can anyone please explain to me what is ...
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How is the nucleus-nucleus CM energy per nucleon related the proton-proton CM energy in a circular accelerator?
If I understand it correctly, the center of mass energy per nucleon pair in heavy ion collisions is given by $$\sqrt{s_{NN}}=\sqrt{(p_a/A_a+p_b/A_b)^2},$$ where $a$ and $b$ label each colliding nuclei,...
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Collision Energy for heavy ions
I found this formula in Sahoo Relativistic Kinematics:
$$\sqrt{s_{NN}}=2\sqrt{s_{pp}}+\sqrt{s_{pp}}\sqrt{\frac{Z_{1}Z_{2}}{A_{1}A_{2}}}$$
But because English isn't my first language i got confused. So ...
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Can I destroy Bennu, if I shoot it with my electron gun? [closed]
The asteroid Bennu seems to be just a pile of rubble weakly held together by gravitational forces. Newton’s law, -Gm1m2/r2, and Coulomb’s law, +keq1q2/r2, have exactly the same form but opposite sign. ...
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Polarized proton beam
Can someone explain to me or point me towards some references about how can one obtain experimentally a polarized proton beam. I find many talks about using siberian snakes to preserve the ...
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Which one is more efficient in producing high energy gamma rays?
According to https://apps.dtic.mil/dtic/tr/fulltext/u2/a351472.pdf the big pulsed power accelerator, HERMES III, generate electron beam with peak energy at 22 MeV and average electron energy at 16 MeV ...
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Generating very large area gamma rays by other ways other than large accelerators
According to this link https://apps.dtic.mil/dtic/tr/fulltext/u2/a351472.pdf, HERMES III at Sandia National Labs can generate very large area gamma rays by converting the electron beam into ...
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Functionality of an Einzel lens
An Einzel lens is a device for ion optics to focus a beam of particles. It consists of three ring electrodes, with the outer ones being on earth potential and the middle one being on high voltage (see ...
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