Questions tagged [particle-detectors]
the tools used to detect (and sometimes) characterize ionizing radiation. This tag is appropriate for question about the characteristics and behavior of all such devices from the simplest Geiger-Muller tube, to the compound monsters used by high-energy experiments to the mega-ton instrumented volume of IceCube.
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Can we detect the alpha and beta particles using the scintillator detectors?
In the experiment gamma ray detection with scintillators, we can detect the gamma ray particle. Is it possible to detect alpha and beta particle using scintillator detectors. If not then why is so? ...
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Why can't indirect ionisation be seen in the silicon tracker of a HEP particle detector?
So the inner tracker system of a particle detector (say CMS) can detect charged particles because they ionize particles in the detector. These inner tracker systems are made of silicon pixels and ...
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How do we know that the muons created by cosmic rays in the upper atmosphere are the same muons reaching our detectors at the surface?
I was reading the summary of most significant experiments done so far verifying muon's Special Relativity time dilation and lifetime extension here:
https://en.wikipedia.org/wiki/...
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What is the probability distribution for the detection times of radioactive emissions from a radioactive sample?
Assume I have a radioactive sample composed of $N$ atoms of some type A. I know that if I measure at time t the number of atoms not already decayed, this number will be given by
$$
N(t) = N_0 \exp\...
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Can spin be used for charged particle identification?
In modern particle physics experiments, identification of charged particles (pions, kaons, muons, protons, electrons) is often required. This is usually achieved with techniques based either on time-...
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How the calculate the energy resolution of a lead crystal calorimeter?
I'm trying to calculate the energy resolution that can be found with a lead crystal calorimeter, and I have the following equation to find the approximate value:
$$
\frac{\sigma_E}{E} = 0.02\% + \frac{...
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Data rate of Atlas and CMS, LHC's detectors too slow?
There is a technical question I always curious about to ask a CERN expert? I have read,
http://nordberg.web.cern.ch/PAPERS/JINST08.pdf, page 5,
that the data sampling rate, number of stills taken from ...
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Is there a way to determine the production method of a Higgs boson created via collisions in the LHC?
So I'm aware that there are several currently accepted production methods for Higgs boson, such as gluon fusion. When a Higgs boson is detected is it possible to determine the production method from ...
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ZEUS Uranium-Calorimeter
According to Wikipedia:
In the ZEUS calorimeter neutral pions interacted with uranium atoms to produce slow moving neutrons which were captured by the scintillator and increased the hadronic signal.
...
user248824
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Does boron trifluoride have to be replaced in a proportional chamber detector with ${\rm BF}_3$?
Does boron trifluoride have to be replaced in a proportional chamber detector with ${\rm BF}_3$?
Boron-10 reacts with a neutron through alpha decay
$$^{10}{\rm B}+{^1}n \rightarrow {^7}{\rm Li}+{^4}\...
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What is a 'kinematic endpoint' in experimental particle physics?
In experimental particle physics, I see 'kinematic endpoint' pop up quite often. I've made an assumption of what it is but now I am not so sure.
Example sentence:
"This region is enhanced in B-&...
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Signal to noise ratio with noise equivalent power
I am reading this document about the noise equivalent power (NEP). I want to calculate the signal to noise ratio for a photon detector.
I denote the signal power as $P_s$. The width of the signal is $\...
user255856
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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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Why some alpha particle tracks shows curvature *without* applied magnetic field?
For the past few months I have been observing alpha tracks with my homemade expansion cloud chamber assembly, trying to replicate early achievements in particle physics using modern, low-cost ...
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How do we measure other particles that are not photons?
I believe most particle detectors are based on either the photoelectric effect, or simply on excitation of atoms by light. Then, the energy resulting from this process is converted into something we ...
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Strange output of Geiger counter
Recently, I got a Geiger counter (si3bg). I applied a 400V voltage and a 1m Ω resistance load to it, and connected a 47K Ω resistor in series. The voltage at both ends of the resistance was measured ...
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How to calculate the Likelihood function of a gaussian pdf
Suppose a model for a flux of (astro)particles $\dot \Phi(E,t)$ (from a supernovae) that depends on particle energy $E$ and time $t$ (from beginning of explosion), and 3 free parameters $T_a, M_a, \...
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Cherenkov light rings instead of solid circles?
Let's suppose a muon emits Cherenkov light while travelling in a medium along a straight line. Let's suppose the motion is perpendicular to a wall which is instrumented with photomultipliers.
Question:...
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Why do gamma-rays and neutrons produce different decay times in scintillation pulses from the same compound?
The basis of pulse shape discrimination is that gamma-rays and neutrons have different decay times of their electronic pulses. What makes gamma-rays and neutrons interact with the same compound ...
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Shape of exclusion plots of WIMP
What is the reason why the exclusion plots of WIMP experiments have that "U" like shape? And what sets the minimum of the curve?
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How do I determine the rest mass of a $J/\psi$ particle from CMS Dimuon Data?
Essentially, I'm using CMS Dimuon data, from the decay of a $J/\psi$ particle, to prove that momentum is 'conserved' in relativistic collisions. However, I'm unable to find how I can do this. I ...
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How can you produce a spectrum with He3 thermal neutron detector?
I'm looking to understand how Bonner Sphere System works. I understand the whole idea, but I'm lost about how a single sphere can produce a whole spectrum.
For instance with He3 thermal detector, the ...
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How do you get the total energy of an event for a detector array?
THE SET-UP: The air-shower detector array made out of six detectors. The detectors are composed of a scintillator and a SiPM (Sillicon Photomultiplier) each. Depending on the shower size, one or more ...
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Question on hidden variable theory of QM [closed]
My understanding from careful study of Bells theorem is that there may be a deep subtlety that is not ruled out, but is probably very minimally studied in the literature. However the literature is ...
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$\rm NaI$ detector rate dependence on distance
I used a $\rm NaI$ scintillation detector to linked to a scalar unit that counts the number of gamma rays detected from a $^{22}$Na source. I repeated the experiment for equal time intervals of 40 ...
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Is it always possible to infer photon distribution from photon statistics?
Say we are detecting light in the time interval $(t,t+T)$ that is described by the intensity $I(t)$. Let the integrated intensity in this interval be given by:
$$U=\int_t^{t+T}I(t’)dt’$$
Since $I(t)$ ...
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Using laser scattering beams instead detectors in Double Slit Experiment?
In the Double Slit Experiment for electrons could be possible the use of an appropriate laser pointer at one slit aiming up so when an electron passes through that distinct slit it get scattered up so ...
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Can atmospheric humidity act as a cloud chamber?
According to wikipedia vapor supersaturation is relatively common (20-40% of the time) in the upper troposphere.
Assuming perfect conditions (such as sufficient visual contrast and no wind), would it ...
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How can a single photon be detected?
It seems possible to detect a single photon.[1, 2]
But the photon is a free particle. Its momentum is decided precisely and it means that the position of the photon is uncertain. The photon can exist ...
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How do we detect particles from cosmic rays whose lifetimes are on the order of nanoseconds?
I have read that the charged pions were experimentally discovered in 1947 using photographic emulsions placed on mountaintops so that as they came from cosmic rays, they wouldn't interact with the ...
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How will the possibility of tritium contamination decay be removed from XENONnT data?
The abstract of the new arXiv preprint Observation of Excess Electronic Recoil Events in XENON1T contains the following sentence:
The excess can also be explained by $\beta$ decays of tritium, which ...
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Fundamental Limits for Photon Detection
In quantum electrodynamics "photons don't have positions". The physical relevance and consequences of this fact has been discussed on this site 1. (Further relevant questions about the concept of ...
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Electron dressing and photon probing
So I have just gone over a lecture on electron dressing whereby an electron dresses itself in a foam of electrons/positrons/photons through photon emission and absorption (see image).
My lecturer ...
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Is it possible to scan matter on an atomic level?
is it possible to develop a model of a piece of ordinary matter and scan it to develop a model of what kind of elements are in the matter? Similar to an MRI scan?
If it's not possible, why? What ...
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Detection of charged particle in optical fiber cable
There is a charged particle source and a light source attached to optical fiber cable which is attached to a light detector.
Is it possible to detect the passage of a charge particle through the ...
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Extracting yields of decays from fits
I'm currently reading various papers on the violation of Lepton Flavour Universality in rare B-decays and I would appreciate some help in understanding the methodology for measuring the ratios in ...
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Scintillation Crystals for Radiation detection
As I understand it, scintillation crystals work by emitting a light pulse when they are hit by a high energy particle. But I'm struggling to find a good explanation of what is causing the light pulse
...
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Detection of alpha particle using semiconductor
I am trying to detect each instance of alpha particle (of about 5.6 Mev). What kind of semiconductor detector (like photo transistor, schottky diode etc) would be apt for this application?
TIA
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What is the evidence for 'billions of neutrinos pass through your body every second'?
This statement is repeated so often that it has become somewhat of a cliche: 'billions of neutrinos pass through your body every second'. For example see 1, 2, 3, 4, 5, 6.
What is the evidence for it,...
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Are Rhenium based neutron flux detectors shielded?
Are most Rhenium based detectors shielded from the nuclear core of a reactor (except for neutrons)?
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Meaning of *supersaturation* in diffusion cloud chamber
While trying to build a diffusion cloud chamber using the "classical" Langsdorf method, which employs a cold plate to create a steep negative temperature gradient, inducing supersaturation in alcohol ...
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Pressing questions about the annihilation of a particle & an antiparticle
A charged particle (e.g. proton) meeting with its own charged antiparticle (e.g., antiproton) annihilates and energy is given off in the form of radiation. Do we have any clue why this happens?
Does ...
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Three-Dimensional Picture from 2D tiles [closed]
The CMS Silicon Pixel detector can create three-dimensional pictures of a particle's trajectory. It specifically says that "because the detector is made of 2D tiles, rather than strips, and has a ...
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Passive dissipator block between two peltier cells seemingly raising overall temperature differential
I am experimenting with stacked Peltier cells trying to build a simple diffusion cloud chamber.
I noticed that when simply stacking two peltier cells the upper side reaches a temperature (around -15 C)...
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How do drift chambers work?
In a drift chamber we know only the distance from the wire by knowing the drift velocity, so how is it possible to reconstruct a 3D image of the particle trajectory?
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What is a 'detection' in QFT?
I don't know about QFT. However, I imagined that in a filed, there's a probability distribution for excitations. Say there are two electrons somewhere - two excitations somewhere in the EM field, so ...
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Cherenkov light reverse cone direction
The Cherenkov cone is emitted along the charged particle direction as many textbooks say.
Detectors like Super-Kamiokande can detect those cerenkov rings and tag the particle as a muon-like ...
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Radius of Curvature - Tracking detectors
Suppose we want to build a tracking detector for acceleration experiments. In particular, the tracking detector is in a magnetic field with strength $B=4 T$ in order to measure the momenta of charged ...
user248824
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Basic concept of interaction probability
In William R. Leo's book(Techniques for Nuclear and Particle Physics Experiments) I could not understand the following:
$P(x)=$probability of not having interaction after a distance $x$
$w \delta x$=...
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What causes the spirals to be inward in the bubble chamber images?
My understanding is that the circular paths are caused by the action of the Lorentz force on the electrons and positrons.
However, I'm not sure why the circular paths are going inward. I have two ...
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