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Questions tagged [experimental-technique]

filling in the unspecified details of elegant-sounding descriptions of experimental methods.

431 questions
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How was the first atomic clock calibrated?

As we all know, atomic clocks are being used to measure time and the GPS system. But I was wondering based on what was the first atomic clock calibrated and how accurate this calibration was based on our standards nowadays?
MichaelScott
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43
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4 answers

Double Slit Experiment: How do scientists ensure that there's only one photon?

Many documentaries regarding the double slit experiment state that they only send a single photon through the slit. How is that achieved and can it really be ensured that it is a single photon?
Drachenkatze
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35
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2 answers

Are the fast axes on Thorlabs quarter-waveplates mislabeled?

Some members of my lab are performing a polarization-sensitive experiment where they need to use a quarter-waveplate (QWP) with the fast axis in a specific direction. In the process of carefully checking all the polarization optics, they discovered…
ARM
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8 answers

Given fluids expand non-linearly, how were physicists able to make a linear temperature scale?

Materials expand with increase in temperature. As far as I know this property for fluids was put in use to make initial thermometers. We know that expansion of fluid is given by the following formula (at a given pressure) (Wikipedia) $$\Delta V =…
user249968
25
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5 answers

How should I clean a part before installing it in a vacuum system?

What are proven procedures for preparing a part that comes fresh out of the workshop for ultra-high vacuum (UHV) and extremely-high vacuum (XUV)?
Martin J.H.
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3 answers

How to fix a bad KF flange?

Here is an interesting question for those who are familiar with vacuum science techniques. In the attached picture we have a damaged surface of a KF flange, which comes from the turbo pump outlet and connects to a roughing pump. We believe this is…
wcc
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25
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4 answers

How do astronomers measure the distance to a star or other celestial object?

How do scientists measure the distance between objects in space? For example, Alpha Centauri is 4.3 light years away.
user230
20
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4 answers

How to prolong life of liquid nitrogen in hosehold vacuum flask?

I need to do some work with liquid nitrogen at home. The main question is how to store it without buying huge vacuum flask specifically for liquid nitrogen. I've tried to use usual steel household vacuum bottles, added ~1 cm of extra insulation…
BarsMonster
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Are there any inventions/applications in our world based on QFT?

Are there nowadays any actual devices or experimental applications which are based on the quantum field theory and if so, how are they related to QFT? I could not find any similar question besides this one.
Statics
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Is there any advantage in stacking multiple images vs a single long exposure?

Suppose I have a source object that is not time varying, to be concrete let's say it's a galaxy. Is there anything additional that can be learned or done with multiple short exposure images of exactly the same field as compared to a single long…
Kyle Oman
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Which experiment gave scientists reason to believe nuclear fission/fusion produced energy?

Every piece of knowledge in science has a beginning lying in someone's experiment. I would like to know which experiment gave scientists the reason to believe nuclear fission/fusion existed and was instrumental in the development of the field of…
Klik
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Multiple measurements of the same quantity - combining uncertainties

I have a number of measurements of the same quantity (in this case, the speed of sound in a material). Each of these measurements has their own uncertainty. $$ v_{1} \pm \Delta v_{1} $$ $$ v_{2} \pm \Delta v_{2} $$ $$ v_{3} \pm \Delta v_{3} $$ $$…
Benjamin Hodgson
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How is time measured in particle experiments?

I was reading about the half life measurements and was curious to understand the experimental setups that allows so minute measurements to be captured. Specifically looking into half life of Higgs boson. I am looking to understand one example method…
Sohail Khan
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16
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3 answers

Measuring the effective mass

Intro: To avoid any terminology confusion, this is asked in the context of Solid State Physics and semiconductors. The canonical definition given for the effective mass is that it is related to the curvature of the conduction and valence bands in…
user929304
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15
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How can we 'see'/measure/detect particles during experiments?

I often read (high-level, conceptual) articles and news on the advances of particle physics. In these, statements are made along the lines of 'particle X splits into particles Y and Z which exist for about a billionth of a second and then decay,…
Asciiom
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