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-1
votes
1answer
103 views

Did we get near Pluto with our current technology? [closed]

I was sent from Skeptic to here. We all know that NASA has successfully carried out the mission for getting near Pluto. More here. It is very difficult for me to accept that we already have the ...
0
votes
2answers
34 views

How to find time when temperature crossed certain threshold?

I have a data from experimental system concerning temperature of molten lead. In this system, temperature is increased in one place and then is measured when this increase of temperature travels to a ...
0
votes
3answers
43 views

Database of experimental cross sections for atomic collisions

Does the atomic-physics community keep a comprehensive database of experimental data (cross sections) for atomic collisions? I am looking for data about Bremsstrahlung, ionization, elastic and ...
13
votes
1answer
258 views

Does my green laser pointer emit three distinct frequencies, or is my measurement flawed?

I was playing around with a cheap diffraction grating and my set of laser pointers, and I noticed that while the red and the blue pointers produce a single point in the spectrum, my green laser ...
1
vote
1answer
95 views

Quantum anharmonic ocscillator $E_0(\lambda)$ curve or table

I am looking for the exact data on $E_0(\lambda)$ for the anharmonicity $\lambda x^4$. The perturbative expansion is the following: $E_0(\lambda)\approx 0.5(1+1.5\lambda -5.25\lambda ...
0
votes
1answer
56 views

Can Black Holes Maintain Data Entropy When Formed By a Data Storage System?

It's been shown that black holes don't destroy information. There's a little-known scenario in computer science (Specifically AI) where an advanced civilization creates an artificial intelligence that ...
0
votes
0answers
48 views

Errorbars for data series with variable number of points and several layers of uncertainty

I'm making a 2D plot of my microwave S Parameter data and want to represent the error bars correctly. Experimental Context: I measure S21, (Vout/Vin), as a function of frequency and drive power with ...
3
votes
1answer
65 views

What does 'channel' mean?

I see many plots like the following that graph counts per channel, I know what a 'count' is, but I don't know what a 'channel' is. Could somebody please explain to me? My guess is that it is that ...
0
votes
1answer
34 views

What does a goniometer (sound) show?

In looking into 2D representations of audio, I came across a tool called a goniometer. I'm aware that a goniometer refers also to a device for measuring angles, but in this context it refers to one ...
0
votes
1answer
31 views

Data processing Data [closed]

Is there anything in the world that data, processes the data? I meant that instead of full utilization of CPU, is there any data or program that handles data/logic processing?
-1
votes
1answer
55 views

Energy stored in hard disk [closed]

What is the type of energy stored in hard disk when data is stored? And Can we use it for electric power production?
0
votes
0answers
23 views

The initial presumed temperature of the universe is derived from data?

When people mention the BBT (*) they assume that it is hot. As late as 1988 it was scientifically proposed a cold BB model (WP) The initial presumed temperature of the universe is derived from ...
1
vote
5answers
148 views

Why is microwave better than visible light for point to point data communication?

In the electromagnetic spectrum, it appears that the shorter the wave length, the better the bandwidth due to higher frequency. Some communication systems utilize microwave to transmit data to offer ...
0
votes
0answers
35 views

Create a transmission protocol to transfer both data and energy(Wireless Communication)

Is there a protocol by which we can design systems that jointly transfer both data and energy ? Some kind of gadget that collects the received energy, temporarily stores it in a battery and later uses ...
1
vote
2answers
407 views

Sellmeier Refractive Index of Standard Air

The question: What is the Sellmeier description of the refractive index of air at some reasonable temperature, pressure, and water content? The description must be in the following form:$$ ...
0
votes
0answers
42 views

Milky Way Density Profile

Does anyone know where I can find either a printed version or, better, a downloadable dump of data giving me the density profile of the Milky Way? I'm looking to put together a quick-and-dirty ...
0
votes
0answers
59 views

Is there a machine readable format of the data tables in Particle Data Group PDFs?

Is there a machine-readable format of the tables of data in PDG documents such as this one? http://pdg.lbl.gov/2011/download/rpp-2010-booklet.pdf Something such as JSON, XML, CSV, HTML, or anything ...
25
votes
8answers
9k views

Since cables carry electricity moving at the speed of light, why aren't computer networks much faster?

Why can't cables used for computer networking transfer data really fast, say at the speed of light? I ask this because electricity travels at the speed of light. Take Ethernet cables for example, I ...
0
votes
1answer
30 views

Nuclear Compton Scattering Data

Is there a repository where one can find unpolarized nuclear Compton scattering data $\gamma (Z,N)\rightarrow \gamma (Z,N)$ for specific nuclei $(Z,N)$? or even some parametrization of structure ...
4
votes
2answers
157 views

Computer parsable table of nuclides

I am looking for an computer parsable (CSV, XML, JSON, since I didn't find anything, I am happy with almost everything) file (or collection of files) that contains the information you can find in a ...
1
vote
1answer
54 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 ...
0
votes
2answers
222 views

List of experimental band gap

does anyone know where one can find a list, database, book of experimental bandgap values of semiconductors? Is there such a collection? Or do I need to scour papers one at a time to get the values?
1
vote
1answer
196 views

Measurements for thermal diffusivity of graphene?

We have known for a long time that graphene has in-plane thermal conductivity ranging between 2000 and 4000 $W m^{-1} K^{-1}$. But in order to model heat transport on a sheet of graphene, we need more ...
0
votes
2answers
232 views

Debye temperature for the steel?

I'm looking for data on Debye temperature of steel (ideally with a known carbon concentration, structure, and set of phases), but find only data on elements. Do You happen to meet the data in papers, ...
2
votes
0answers
68 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
53 views

Does speed of writing data on an optical disk affect the speed of reading data? [closed]

Does speed of writing data on an optical disk ( like DVD ) affect the speed of reading data from that disk ? even a little?
1
vote
2answers
175 views

Is there a star catalog for download?

Is there a downloadable star catalog which not only includes positions, but also spectral class, size, etc.? A CSV file would be great for the sake of easiness.
11
votes
1answer
284 views

Statistical analysis of data in Physics

Analysis of data is integral in bridging the gap between theory and experiment. How much do the results of the analysis depend upon the choice between Bayesian and frequentist methods? For instance, ...
1
vote
1answer
75 views

Transmutation with cosmic radiation possible?

Can cosmic radiation (alpha radiation) transmute the material of a space craft, particular carbon, titanium and aluminum? Where can i find transmutation tables or formulas to calculate the ...
2
votes
0answers
90 views

Intensity of particles with zenith angle dependence

The intensity of particles come to sea level depend to the zenith angle $I=Iv (\cos(z))^n$, where $z$ is the zenith angle and $n$ depend to the particle. I know the vertical intensity depend to the ...
1
vote
1answer
68 views

Astronomical measurements and data

For the sub-nuclear physics there is a database of the Particle Data Group, I was wondering if there was a similar on-line collection for astrophysics, such as energy absorption and emission spectra ...
0
votes
2answers
2k views

How is data physically written, read and stored inside hard drives?

How is data physically written, read and stored inside hard drives? Is it stored as differing spin of atoms inside the drive? Is that method the same in flash drives and SSDs?
3
votes
0answers
93 views

Where does one find pair-correlation functions for various materials?

What is the canonical source for finding pair-correlation functions for atoms in various materials? I am interested in both numeric computations and experimental measurements (like might be obtained ...
0
votes
0answers
64 views

Lambda transition data points of $\require{mhchem}\ce{^4He}$

I'm looking to get some data on the lambda transition of $\require{mhchem}\ce{^4He}$. I need the data points of the specific heat vs. temperature graph, if that makes sense.
3
votes
1answer
85 views

Where can I search for high quality telescope images of Earth's moon?

I am developing a sensor calibration capability that compares a telescope lunar observation to a physics-based radiometric model. I'd like to find some high quality lunar images to test our ...
1
vote
0answers
42 views

where to find sample fluid stirring data?

I want to find some force data for fluid stirring. Originally I intended to record the data using my force sensor, but it doesn't have the resolution to read stirring force for Newtonian fluid. ...
0
votes
0answers
77 views

Experimental data for gas flow through pipelines

Maybe some of you could point a good source of experimental data of gas flow through pipelines? What I need is a very simple flow of some gases through some diameter simple linear pipeline. A graph of ...
1
vote
0answers
72 views

What is your prefered toolkit / program for 3D visualisations of data? [closed]

If you recorded data which represents some physical value in space (e.g. electron density) and you need to explore this dynamically in 3d (say you have a isosurface and you change the value it ...
5
votes
2answers
540 views

Does sending data down a fiber optic cable take longer if the cable is bent?

Ok, so, my simplified understanding of fiber optics is that light is sent down the cable and it rebounds off the sides to end up at its destination. Which got me thinking, if it has to bounce more ...
1
vote
2answers
247 views

Where to find cross section data for e- + p -> p + e-?

Where to find cross section data for e- + p -> p + e-? PDG's cross section data listing does not include it.
0
votes
1answer
537 views

Where to find experimental/theoretical value of (charge) radius of particles?

Where to find experimental/theoretical value of (charge) radius of particles like proton, neutron, $pi^+$, etc. ?
2
votes
2answers
126 views

Question about interpreting PDG particle cross section data sets' metadata fields

I have some question about interpreting PDG particle cross section data sets' metadata fields. The data sets I'm having questions for are http://pdg.lbl.gov/2011/hadronic-xsections/hadron.html For ...
0
votes
1answer
101 views

OPERA. Dates of figure 10

What are the real dates that are represented in the figure 10, page 17, in the OpERA paper Imo the X axis labels are inconclusive, or absent. (in the investigation of a crime it is relevant ...
5
votes
6answers
372 views

Are there free data available online from cosmology (or astrophysics) experiments that anyone can analyse?

One can understand a subject better in physics by trying to solve as many problems as one can from a textbook say. When it comes to experimental physics and data analysis, no book on experimental ...
7
votes
2answers
788 views

What does the data in various stages of analysis from a particle collision look like?

I've been following the news around the work they are doing at the LHC particle accelerator in CERN. I am wondering what the raw data that is used to visualize the collisions looks like. Maybe someone ...
2
votes
1answer
763 views

Refractive index of organic solvents in near-infrared

I wonder if the refractive index of acetone, ethanol, methanol, heptane was measured in the range above 830 nm. The site refractiveindex.info provides it only for visible, and I couldn't find any ...
2
votes
1answer
187 views

Cassini 's and Pioneers RTG power output datafile

I'd like to have access to the datafile of the electrical output of the RTG (Radioisotope Thermoelectric Generator) of the Pioneer's and Cassini missions, as can be seen in the figures 1 of the ...