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1answer
86 views

Does $R=\dfrac{4q^2}{\pi^2a^2gH^2}$ suggest a square root relationship?

I did an experiment involve how R scales with q (the other variables are constant), and I got a relationship like $R\ \propto \sqrt q$ I have been told to evaluate my findings with those in ...
0
votes
1answer
19 views

How to compute $L_{\rm eq}$ from temporal pressure data

I have pressure vs time data. how can I compute sound equivalence Level $L_{\rm eq}$ in decibels? can this be done from a frequency spectrum assuming that it is constant?
1
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0answers
34 views

Looking for binning software [closed]

I'm looking for a software which should do the following Take a set of data $X$ and $Y$: Procedure A Finds the max and min in $X$ Divide this interval in a number of bins chosen by me For each bin ...
2
votes
1answer
171 views

Rutherford Experiment - practical and theoretical questions

I performed the Rutherford experiment the other day, using Au thin foil of $2\,\mathrm{\mu{}m}$, a source/gun of α particles (241Am) and a detector/counter. α particles were shot from the source ...
4
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1answer
42 views

How do you measure neutron energy?

I think you can detect a neutron event with a scintillator (neutron to photon), photomultiplier tube (photon to electric signal) system, but how would a fusion neutron's energy (2.45 MeV) be typically ...
1
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1answer
53 views

Looking for an Time Series Analysis Text [closed]

(Apologies, I could not think of a better title). Two days ago, I was in the Library at Köln (Those who know it, knows that the books are not ordered by subject - but by date of buying, and one has ...
1
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0answers
73 views

Coherent Intermediate Scattering Function from Simulations

I want to calculate the coherent intermediate scattering function, $S_{\text{coh}} (\mathbf{Q},t)$, from a molecular dynamics trajectory, based on its definition. The definition of the function is: ...
0
votes
2answers
35 views

Peak at zero in one device and not the other

I was wondering if anyone could shed some light on this problem. I have placed two accelerometers on an animal one sampling at 50 Hz the other at 100 Hz. They were placed in the same position. I then ...
0
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0answers
2k views

How to calculate lattice parameter of wurtzite struture

I am trying to calculate lattice parameter of ZnO (wurtzite). I have found out the formula for calculating lattice parameter of this system from a research article. $\frac{1}{^{d^{2}}}=\frac{H ^{2}+ ...
0
votes
1answer
31 views

Nuclear explosion wavelength data

I am looking for data source (or chart) of spectral data that is being emitted on detonation of nuclear or thermonuclear explosion. Reason I am looking is to see if this data has specific signature ...
0
votes
1answer
56 views

Using Audacity to generate power spectral density

Say I record something with a sound recording program like Audacity (e.g. plucking a guitar string). How could I use that recording to plot a dB vs Frequency graph?
5
votes
1answer
140 views

Data requirement to determine proportionality

A common result of theoretical analysis in physics is some sort of relation derived from physical parameters and typically expressed in the form of a non-dimensional parameter. These scale relations ...
3
votes
1answer
61 views

Absorption line detected with a significance of $2.2\sigma$

What do we mean by the following statement? The SV $\lambda$ 786.46 line is detected with a equivalent width of $W = 22.7\pm10.2$ corresponding to a significance of $2.2\sigma$ How does one ...
0
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0answers
32 views

Open-source up-to-date cosmological datasets [duplicate]

Where could I find open-source up-to-date cosmological datasets? Are there any available as a data stream with an API? I already know about these: http://cas.sdss.org ...
5
votes
2answers
677 views

What is meant by “combinatorial background” in experimental high energy physics

My guess is that they find a certain tracks coming from a certain source by "combintaorially" selecting all track pairs and finding their invariant mass. If this is true, of which I am not sure, how ...
2
votes
1answer
53 views

Decay/Counts/Number of Nuclei

I'm writing up a lab report and have a question about the following formula $$N = N_0e^{-\lambda t}$$ $N$ indicates the number of nuclei left after a time $t$ and $N_0$ indicates how much there was ...
2
votes
2answers
114 views

Franck and Hertz graph function [closed]

I need a function whom graph is the following (the Frank and Hertz experiment graph): Currently I wrote the following function: ...
1
vote
1answer
35 views

What is the correct way to handle significant figures when calculating compound uncertainties? [duplicate]

When processing experimental data, and calculating an uncertainty value in multiple steps, should intermediary uncertainties be used to a certain number of significant figures or kept to the full ...
10
votes
2answers
597 views

Use of Monte-Carlo simulation in High-energy Physics

I've been doing some research into the analysis used in particle physics when determining the significance of a finding (e.g. the recent Higgs candidate was announced as a boson in the 125-126 ...
0
votes
1answer
26 views

how find resonance in extrasolar planet? [closed]

I make this program, i have a 2xN matrix in which the columns are the ID of planets and their period, the rows are the number of planets, for istance something like that: ...
1
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2answers
278 views

NMR Analysis of Ethylene glycol [closed]

I have the spectrum obtained by an NMR analysis of Ethylene glycol : I would like to explain the number of peaks in this spectrum, and assign them to the proton spins present in the molecule. I ...
1
vote
1answer
47 views

Collection Efficiency of Photon

I am currently reading this paper: http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.112.116802#references In the second column of text in page 2, the author makes various claims about the ...
1
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2answers
48 views

Data for binary systems

I am looking for binary systems data that can be used in the context of Kepler's laws. Masses, distances, periods, etc.
1
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0answers
41 views

How to calculate tortuosity of a signal? [closed]

Not sure which stack exchange forum to put this in. Moderators feel free to migrate it. One definition of the tortuosity $T$ of a curve is: $$T=\frac{C}{L}$$ Where $C$ is the chord length ...
-1
votes
1answer
127 views

What are the problems in analyzing an experiment with non-ideal collisions? [closed]

For a two-dimensional collision experiment, I must explain in one of the questions the problems in analyzing a non-ideal two-dimensional collision. As the question states: Suppose that the ...
0
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2answers
72 views

Function for curved line in log-log-plot

I've done experiments on the thermo-viscoelasticity of liver tissue and the following results ...
4
votes
1answer
285 views

Calculating Lyapunov exponents from a multi-dimensional experimental time series

Wolf's paper Determining Lyapunov Exponents from a Time Series states that: Experimental data typically consist of discrete measurements of a single observable. The well-known technique of phase ...
8
votes
2answers
543 views

Does a muon detector on Earth's surface correctly measure the mean lifetime of a muon?

Just a simple question. Does a muon detector on Earth's surface correctly measure the mean lifetime of a muon? I would think the answer is no because most muons detected are created about 15 km above ...
3
votes
1answer
2k views

Where are the ice rings in X-ray crystallography located?

I threw this image of one of my protein crystal's diffraction pattern (not the greatest) on a poster, and was wondering where (what reciprocal dimension) the ice rings are located as it might be a ...
0
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0answers
39 views

How to analyse data that is in four dimension?

I have obtained a series of data that is about density distribution of liquid in three dimensions, density$=f(x,y,z)$. How can I know the detail information about the way that density changes with $x$ ...
10
votes
1answer
761 views

Which areas in physics overlap with those of social network theory for the analysis of the graphs?

I am studying social networks in terms of graph theory and linear algebra. I know that physicists have published and worked a lot in this field. This causes me to assume that there are sub-fields in ...
3
votes
1answer
102 views

Combining uncertainties - multiple measurements

I am trying to understand how to combine uncertainties when they are dependent and independent from each other. Using this formula : $$\delta z = \sqrt {\Biggl(\dfrac{\partial f}{\partial x} \delta ...
0
votes
0answers
124 views

What about assessing negative Limit of Detection for concentration

I recently came in a work-group discussion where I think some concepts are misused. After seeking for scientific articles on the subject I have found that part of the problem is definition (what ...
5
votes
1answer
226 views

Advanced data analysis in Physics experiments

Before answering, please see our policy on resource recommendation questions. Please try to give substantial answers that detail the style, content, and prerequisites of the book or ...
4
votes
1answer
129 views

How do I calculate the experimental uncertainty in a function of two measured quantities

I am performing an experiment where I'm measuring two variables, say $x$ and $y$, but I'm actually interested in a third variable which I calculate from those two, $$z=f(x,y).$$ In my experiment, of ...
5
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0answers
92 views

Textbook about the handiwork of a HEP analysis?

I'm wondering if there is a textbook that describes the handiwork of a particle physics analysis. There are a bunch of books about theory, about the experimental aspects like detectors, and about ...
3
votes
1answer
121 views

Reference request: statistical inference with real world (chaotic) data, e.g. climate/weather data

I'm interested in the process that goes from, for example, huge data sets of temperature, pressure, precipitation etc readings to a model of the atmosphere. I'd like to know about how much relies on a ...
1
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0answers
73 views

What could be the distribution of an explosion energy of a mining-grade and seismic exploration explosives?

Seismic exploration involves the excitation of seismic waves using the industrially made explosive charges. What could be the distribution of explosion energy of such a charges? My guess is that it ...
3
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0answers
49 views

Converting impact speed to pressure magnitude

In explosive safety and stability testing, a drop test is commonly used to determine the sensitivity to impact. In the test, an impactor of known mass is dropped. The initial height varies throughout ...
1
vote
1answer
1k views

Uncertainty in Acceleration given the uncertainty in position

I had a motion detector record the position of a dynamics cart and automatically plot Position vs Time and Velocity vs Time plots in Logger Pro on the computer. If the instrument uncertainty in ...
0
votes
2answers
175 views

1/r Counting Rate for Radiation Experiment

In an experiment performed in the lab, I want to justify that, when the width of the Geiger counter window is approximately the same size as the distance between the window and a mildly radioactive ...
2
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0answers
23 views

Expression for combining several probabilities in a single discriminator

I'm doing an analysis of some experiment. Details are not very important, but I've stumbled on an expression that I cannot make sense of. I have several simultaneous measurements of a certain ...
0
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0answers
36 views

What star catalog is suitable for a programmer wanting to model observable stars in 3D?

I have searched around the web and looked at Wiki entries and I am overcome by the number of catalogs available. What I want is a catalog that includes all objects you might conceivably see with ...
2
votes
1answer
89 views

What are anticipated events and experimental uncertainty?

I am working on this lab that involved gathering data from two different sources. It involved gathering reaction times from a device and from a web application which was put into our data sets. It is ...
1
vote
1answer
76 views

Curve Fitting and Multiple Experiments

Say I do an an experiment 5 times, each of which gives you a list of data points. Do I fit a curve to each one separately and then average the parameters and their uncertainties? Or do I take the ...
1
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0answers
47 views

Where can I get latest full updated list of supernovae candidates from the SDSS-II Supernova Survey?

I am doing a project where I need the list of supernovae candidates from the Sloan Digital Sky Survey II (SDSS-II) supernova survey. One list is available as part of the data-release-7 (DR7) website. ...
1
vote
1answer
22 views

Choice of color for graphs with filled area [closed]

I am writing an article and the central results are summarized in a graph so I want it to be very beautiful and physically intuitive. It has 3 regions in which a certain quantity is conserved, ...
0
votes
0answers
60 views

Where can I find how to do data analysis for a magnetic hysteresis loop?

I am given a data set that has a hysteresis loop but there's a diamagnetic signal that I understand needs to be subtracted, but I don't know the how this is done. I remember finding the slope of the ...
3
votes
1answer
42 views

Asymmetry in muon energies of public CMS dimuon event data

CMS published for educational purposes (caveat) 100.000 dimuon events: https://cms-docdb.cern.ch/cgi-bin/PublicDocDB//ShowDocument?docid=11583 As one easily sees, column 4 shows the first muon's ...
6
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0answers
122 views

Statistical analysis of data in Physics

Analysis of data is integral in bridging the gap between theory and experiment. My question is about the two major methods of approaching the analysis - Bayesian and Frequentist. How much do the ...