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0
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0answers
30 views

how can I detect cosmic muons from background?

Is there anything I should be careful with if I would like to detect muon at sea level? Noise background? Threshold? Even signals from other particle with stronger flux rate?
0
votes
0answers
23 views

Statistics: combining independent observables for the same quantity, how to check independence? [on hold]

Let's assume we have a set of observations $\{x_i\}$ and that I have a physical models aimed to describe the observations, and that this model has a parameter $y$. Let's assume that I have two ...
-3
votes
0answers
19 views

Electric circuit [closed]

The galvanometer reads 1A full scale means a current of Ig= 1A produces a full scale deflection of the galvanometer needle. The needle deflection is proportional to the current Ig. If you want the ...
0
votes
1answer
25 views

Sloan Digital Sky Survey (SDSS) spec file headers

I downloaded spectra from Sloan Digital Sky Survey (SDSS), which has the following column headers flux, loglam, ivar, and_mask, or_mask, wdisp, sky and model (...
2
votes
0answers
30 views

What is the difference between selection efficiency and acceptance in high energy physics?

Often in papers the product of these two quantities is mentioned, but I'm not sure what exactly they mean separately. My guess would be that one of these is the fraction of the events that you are ...
1
vote
0answers
14 views

Data Analysis: Image Sharpening through Posterization

I had this image, a picture of Jupiter: I wanted to measure the pixel diameter of Jupiter. As evident, the image is quite blurry, and thus, many value of equally justified pixel diameters can be ...
-4
votes
0answers
24 views

Data offset (radial velocity) [closed]

To work out an estimate for the period, I need something called the data offset. My data is measured radial velocity for certain times. What's the data offset and how do I work this out? They're ...
2
votes
1answer
38 views

What do the terms “offline” and “online” refer to in the field of high energy physics data analysis?

The title says it - I've encountered these terms several times but have never found an explanation anywhere. An example of use is this ATLAS note. If I may hazard a guess: Data rate is high at the ...
-1
votes
0answers
20 views

Online rotation curve data search

I would like to know how to find rotation curve data online. I know there are online data bases like hyperleda, ned, simbad, etc. but how to look inside those projects for the rotation curve data?
-3
votes
0answers
15 views

How to estimate period of sinusoidal (exoplanet radial velocity) data?

I have an exoplanet's noisy radial velocity data collected over a period of time. I want to write python code that will determine an estimate for the period of this data. I've heard of ...
-1
votes
0answers
16 views

Importance Samling in Monte-Carlo-Integration

I have posted a question on importance sampling on data science stackexchange but haven't gotten an explanation yet. Since Monte-Carlo methods are usually to some extend needed in physics I would want ...
4
votes
2answers
58 views

Combining two data points with different uncertainties

I have two separate algorithms (call them "A1" and "A2") which reconstruct the $(x, y)$-position of an event in a particle detector. I can test both of these algorithms on simulated events from a very ...
0
votes
2answers
55 views

Least Squares Fitting - 68% Confidence Interval

I am fitting a linear polynomial to some data and I have derived the errors for each of the best-fit parameters from the covariance matrix. I would expect these errors to correspond to a $1\sigma$ 68% ...
1
vote
1answer
238 views

Calculating jerk vs Fitts law for smoothness

I've tracked the movement of an input method resulting in this dataset. All data is tracked with equal intervals of 100ms. For example an iteration value of 4 means that this is the position of the ...
0
votes
1answer
37 views

Subtracting Audio from a Song with Multiple Forms

This question may start oozing into the realm of copyright infringement, but let's discuss the theory first and foremost. I have a song with vocal and orchestral accompaniment from a well-known movie ...
1
vote
1answer
33 views

Gamma Ray Burst data

I wanted to know if there was some database for gamma ray burst (GRB) data. I would like to get the luminosity and duration of recorded GRBs. So far, I have come across this website, but since I do ...
3
votes
2answers
72 views

Best way of calculating average acceleration in lab experiments

I am doing a lab experiment that works as follows. An object moves along the $x$ axis with an initial acceleration and then moves with a pretty constant velocity that may slightly vary within $20\%$ (...
3
votes
0answers
30 views

Normalizing temperature data of CPU sensors to ambient

My scenario: I want my application to stop or take some decision based on temperature. say like if my ambient is morethan 41 i want to switch off the application and we do not have an separate ...
0
votes
1answer
32 views

Why is the standard deviation the error on the singular measurement?

I'm a beginner with the study in data analysis in Physics. I'm trying to understand the meaning, in the field of experimental Physics, of the standard deviation $\sigma$ of a series of data. There ...
11
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2answers
19k views

How do you find the uncertainty of a weighted average?

The following is taken from a practice GRE question: Two experimental techniques determine the mass of an object to be $11\pm 1\, \mathrm{kg}$ and $10\pm 2\, \mathrm{kg}$. These two ...
4
votes
0answers
50 views

Calculating statistical significance of peak over background in counting experiment

I histogrammed the invariant masses of particular events in a counting experiment. There is a specific peak which towers over the expected exponential background. How can I give the statistical ...
1
vote
1answer
27 views

Should I see evidence of neutron induced gammas on a background spectrum?

If I am looking at a background gamma spectrum taken from a neutron spallation source whilst the beam was off (IE in a shutdown period), should I expect to see emissions coming from neutron induced ...
2
votes
2answers
163 views

What is the Benefit of Plotting a Log of Net Force vs. Log of Acceleration Graph?

In preparation for a quiz, I've been going over a set of sample questions. One question in particular asks that if I am to graph the logarithm of the horizontal net force of a system vs the ...
0
votes
2answers
17 views

Interpolating experimental data correctly (limited model knowledge)

I have data which I know follows a function $y = f(x)$ such that it is quadratic i.e. $y =\alpha x^2$ for some $\alpha$ when $x\rightarrow 0$ and $y = \beta x$ for large $x$. The data itself has ...
1
vote
0answers
25 views

Sine wave in my residuals graph [closed]

We had a physics experiment where we should have had a linear relation between 2 measured values, we got a pretty good fir however our residuals plot has a kind of a sine wave behaviour. We were told ...
0
votes
1answer
52 views

Choosing curves in data fitting [closed]

I have got a series of data points in experiments. And now I am trying to do some fitting job. What kind of curve should I select for this if I don't know what the exact expression is?
2
votes
0answers
45 views

How is Spin experimentally determined?

I know what spin is and how theories determine it for particles. What I don't understand yet, is how people, through experiments and data analysis or whatever, reach to confirm/say that the $X$ ...
1
vote
1answer
446 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
0answers
12 views

Where can I find Lorentzian values for the width of spectral lines for fitting XPS data?

I'm trying to curve fit my XPS data. I would like to start with known parameters to have an idea. Does anyone know of places the Lorentzian (and even the Gaussian) of elements is located?
2
votes
1answer
279 views

Is Machine Learning a useful tool for analyzing experimental data? [closed]

Apart from being a student of Physics I'm also a developer and recently in the context of cloud development I've been hearing a lot about cloud based Machine Learning. After looking at some examples ...
0
votes
1answer
14 views

Why does natural counting with a gamma spectrometer differ from Neutron activation analysis?

As stated in the title, why are the data from natural counting using s gamma spectrometer different than the data from neutron activation analysis using the same samples?
1
vote
2answers
48 views

Problem with denoising BICEP2 data?

This question pertains to this article which talks about why the BICEP2 measurements of B-mode polarization in Cosmic microwave background radiation turned out to be noise from galactic stardust. They ...
1
vote
0answers
15 views

Starter projects/visualizations/analyses? [closed]

I just renovated a desktop that had been in storage for a while and I am looking for good ideas for data analysis or numerical analysis projects in physics. I have taken up to E&M, and special ...
7
votes
1answer
152 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 ...
0
votes
0answers
43 views

Data analysis for a magnetic hysteresis loop

I'm a physics undergrad and I have MOKE data for a magnetic material (thin permalloy film on a silicon substrate). Here is one of the hysteresis loops I obtained, plotted using python: The form of ...
2
votes
1answer
37 views

What does it mean for a map to be “coadded”?

So there is this wiktionary definition of coaddition, but it's rather brief. Could anyone expand on this, perhaps giving a short example and explaining why its useful? The context that I initially ...
1
vote
1answer
40 views

Karhunen-Loeve transform of a repeating process

This question is inspired by measurements of an unsteady flow. I have some doubts about interpretation of principal component transform using Karhunen-Loeve theorem. I have (centered $\equiv$ zero ...
0
votes
1answer
78 views

Decide Refractive index of a unknown piece of glass [closed]

Problem: The task is to find $n_2$ by Fresnel's equation from given data. My attempt at solution: I begin from this equation: $$R= \left|\frac{(n_2\cos\theta_i - n_1\cos\theta_t)}{(n_2\cos\theta_i ...
3
votes
2answers
85 views

What exactly is an arbitrary parameter?

I was reading the article Turning Points: A meeting with Enrico Fermi by Freeman Dyson (available e.g. here), and I had a question about Dyson's use of the term 'arbitrary parameter'. More ...
0
votes
0answers
17 views

Gamma spectroscopy - Extractable information from peak significance changes?

Apologies for the title - I couldn't think of a better way to summarize my question I have a table which contains information on 60 gamma spectra taken over a total period of 20 days, from the hall ...
5
votes
1answer
316 views

Advanced data analysis in Physics experiments

I know that regression, chi-distribution, covariance, error propagation, etc. are frequent tools for experimental physicists. So, I'd like to know if advanced statistics topics are used in data ...
3
votes
1answer
39 views

Machine readable database of gamma lines

Friends of mine did a lab experiment where they recorded $\gamma$-spectra in the range from 0 to 1500 keV with a soil sample. The data contains some background and a couple sharp peaks at different ...
1
vote
2answers
35 views

Gamma spectroscopy - Fitted Singlet

I'm using some gamma acquisition and analysis software. When I ask the software to do some sort of Nuclide Identification, almost every single peak in the generated output is marked with "F". ...
10
votes
2answers
209 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
79 views

Error in total counts

I'm performing a radioactivity experiment where I measure a specific number of counts in some time period t. Later on I take the total count rate. (Number of counts/time: $N/t$) I'm supposed to find ...
5
votes
3answers
786 views

What does it mean to “bin” in a spectroscopy context

In the following online article http://www.star.le.ac.uk/~sav2/stats/a.html I see the word "bin" used, in relation to x-ray spectroscopy, both as a verb and as a noun (people both "bin" things and ...
0
votes
2answers
40 views

Filament lamp $(V,i)$ behavior between 0 and 1V

I was wondering why the behavior is more "chaotic" at 0~1V when compared to 2V+ (which is when it starts to glow).
8
votes
2answers
447 views

Arrhenius Fit: Linear or exponential form?

I have a seemingly easy question about performing an Arrhenius fit to the equation $$y = A \times \exp \left( -\frac{E_A}{RT} \right)$$ I can either fit this in the exponential form using a non-...
-3
votes
1answer
47 views

Need Some Help Creating A Couple Of Equations [duplicate]

I've posted about this project before as math is not at all my strong subject anymore. I have a couple sets of data and I need to make some equations for them. I've used Excel to get trend lines, but ...
8
votes
2answers
931 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 ...