Shot noise Definition and 14 Threads
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A Expression of Shot noise when expanding ##a_{\ell m}## coefficients
I would like to arrive at the following expression for the quantity ##o_{\ell}## ( with "DM" for Dark Matter ): ##o_{\ell}=b_{s p}^2 C_{\ell}^{D M}+B_{s p}## with Poisson noise ##B_{s p}=\frac{1}{\bar{n}}(\bar{n}## being the average number of galaxies observed). the index "sp" is for spectro...- fab13
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- Coefficients Cosmology Expression Legendre transformation Noise Poisson distribution Shot noise
- Replies: 2
- Forum: Astronomy and Astrophysics
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A Add factor Δℓ or Δℓ^2 in the variance for integrated Shot noise
I have the following expression for an error on a Cℓ : ##\sigma(C_{\ell,X})=\sqrt{\dfrac{2}{(2 \ell+1)\Delta\ell \,f_{\mathrm{sky}}}}\left[C_{\ell,X}+N_{X}(\ell)\right]## where ##X## corresponds to spectroscopic/photometric shot noise and with ##\Delta\ell## is the bin width between 2 values... -
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A Expression of the mean and variance of spectroscopic Shot Noise
Hello, I would like to know the right expression for the expression of variance of Shot noise in spectroscopic probe. Sometimes, I saw ##\sigma_{SN,sp}^{2} = 1/n_{sp}## with ##n_{sp}## the average density of galaxies, whereas my tutor tells me that ##\sigma_{SN,sp}^{2} = 1/n_{sp}^{2}## , so I... -
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Poisson distribution and Shot Noise
My setup: I have the an LED (LED370E) in front of a photodiode (S12915-16R). The photodiode is connected to an ADC (DT5751) which has a counting functionality. The way it works is that it counts how many times the signal goes above a certain threshold and makes a histogram out of it. I know...- Frigorifico
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- Distribution Noise Photodiode Photon Poisson Poisson distribution Shot noise
- Replies: 7
- Forum: Electrical Engineering
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How Does Shot Noise in a Photodiode Lead to White Noise Characteristics?
Not really sure where this belongs... But here goes: If you illuminate a photo diode it generates a current because electrons are being emitted from its cathode. Since each emission is however an independent stochastic process the output current will be subject to fluctuations, which can be...- aaaa202
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- Diode Noise Photo Shot noise
- Replies: 2
- Forum: Classical Physics
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Is It Shot Noise or Avalanche Noise in Your Circuit?
I frequently see the following circuit being used as a noise generator: ... where the transistors are basic npn bipolar transistors. Some authors attribute the noise to shot noise while others say it is avalanche noise. How do I determine which is correct?- Mr Peanut
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- Noise Shot noise
- Replies: 3
- Forum: Electrical Engineering
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Signal to noise ratio for thermal and shot noise
Homework Statement The output of a sensor which produces 10000 electrons is connected to parallel RC circuit with Resistance= 50 ohm, and the capacitance=10pF. Calculate the signal to noise ratio at temperature 300K. Homework Equations SNR= 10 log (power of signal/ power of noise) Or...- Outrageous
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- Noise Ratio Shot noise Signal Thermal
- Replies: 4
- Forum: Introductory Physics Homework Help
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How Can I Reduce Shot Noise in a Phototransistor Audio Application?
Citizens of Physicsforums. I would greatly appreciate your advice. I've been wrestling with a pesky noisy phototransistor for quite a long time, and am at wit's end. The sensor is being used to transuce an audio signal in the 1-5kHz range. Unfortunately the shot noise is introducing...- MaximumPower
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- Noise Shot noise
- Replies: 43
- Forum: Electrical Engineering
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Photocurrent shot noise correlation function
Hi I have stumpled upon the following expression for the correlation function of the photocurrent shot noise for a photodiode <\delta i(t)\delta i(t+\tau)> = \frac{e^2\eta}{h\nu}P\delta(\tau) where η is the quantum efficiency and P the power in the signal. δ(τ) denotes the Dirac delta, which...- Niles
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- Correlation Correlation function Function Noise Photocurrent Shot noise
- Replies: 3
- Forum: Atomic and Condensed Matter
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Johnson and Shot noise the Frequency Term
I am a bit confused over the frequency term that appears in Johnson and Shot noise formulae. What is this term? Is it bandwidth? Of what? In relation to say a photodiode, is it the range of frequencies being detected? And how would this relate to say a DC circuit which no frequency terms...- Master J
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- Frequency Noise Shot noise Term
- Replies: 1
- Forum: Electrical Engineering
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Johnson and Shot Noise at 20*C with 9V Battery and 100Kohm Resistor
A battery of emf 9V, and negligible internal resistance, has a 100Kohm resistor connected across its terminals. What are the values of johnson and shot noise at a temperature of 20*C if the measurement bandwidth is 10KHz? At what temperature would the johnson and shot noise contributions to...- Myrddin
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- Noise Shot noise
- Replies: 2
- Forum: Advanced Physics Homework Help
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MATLAB Adding Signal and Shot Noise in MATLAB - MB's Question
hello well I have 2 vectors in MATLAB each representing a signal+shot noise. I have to add them. Can anyone tell me what the signal noise ratio will be when they are added? thanks MB- evidenso
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- Matlab Noise Shot noise Signal
- Replies: 8
- Forum: MATLAB, Maple, Mathematica, LaTeX
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Can You Combat Johnson Noise and Shot Noise in Instrumentation?
I was wondering if someone could give me some ways to combat Johnson noise and shot noise. Thanks- ultimateguy
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- Noise Shot noise
- Replies: 4
- Forum: Advanced Physics Homework Help
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What is shot noise and how is it estimated in galaxy surveys?
I am reading about galaxy surveys. I want to know what is shot noise ? how we estimate it into real and Fourier space ? I am basically reading astro-ph/0503603 & astro-ph/0503604. I am not able to solve exercise 4, 5, 6. I will be thankful, if anybody can provide me some reference.- cosmo_boy
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- Estimation Galaxy Noise Shot noise
- Replies: 1
- Forum: Astronomy and Astrophysics