Questions tagged [experimental-technology]
Use this tag for questions pertaining to the limits, management, and operation of equipment necessary to experimental physics. This tag is not intended for "does this thing I heard about actually work" type questions.
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How accurate is coincidence counting, and how do we know?
Experiments that feature the creation of entangled photons through SPDC often make use of coincidence counters. How can one photon be accurately correlated with its entangled partner by a coincidence ...
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Can BBAR coatings be neglected in refraction problems?
I am a total novice to experimental optics problems, so I apologize if this is naive. I am wondering whether I can neglect a BBAR coating when calculating an angle of refraction at near-normal ...
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Why were multiple layers of absorbers and scintillators used in the CMS HCAL?
Why were multiple layers of absorbers and scintillators used in the CMS HCAL? Couldn't they have used just one absorber and one scintillator layer? Why was the choice made to have multiple layers?
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When X-ray produced why 99% of the energy is in the form of heat and 1% in the form of X-rays. Why it it not more then that?
When the electrons hit the anode in an X-ray tube, 99% of their energy is released in the form of heat and 1% of that energy is X-rays. Why it is only 1% and not 2% or 3%?
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Do we experimentally know how a magnet reacts in a curling / non-zero-curl magnetic field?
There are two possible formulas for the magnetic force on a magnetic dipole moment due to the inhomogeneity of the magnetic field:
$$ \vec{F}_{A} = \nabla (\vec{m}\cdot\vec{B}) \qquad\text{ and }\...
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How efficient are coincidence counting techniques?
Obviously there is a limitation as to how well experimental configurations that depend on coincidence counting can efficiently remove the noise present at any given experiment. This leads me to ...
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UHV chamber starts oscillating once the pressure gets down to $2.5 \times 10^{-5}$, Why?
Using a new Edwards nXDS15iC scroll pump as a roughing pump for a new Kurt Lesker EMT3304 turbo pump. Chamber is a cylinder about $100{\textrm{ ft}^3}$. We have identified leaks and corrected using a ...
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How hard is it to obtain perfect alignment of optical equipment?
While reading a published paper, I read that some photons were being detected at the arm of a Michelson interferometer which was intended and set to have approximately perfect deconstructive ...
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Are there any specifications required for the computer which would be connected to Computer Automated Measurement and Control (CAMAC)?
I wanna buy a computer to use with Computer Automated Measurement and Control (CAMAC).
Are there any specifications required for the computer which would be connected to CAMAC?
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Efficiency of Geiger-Muller tube
What are the factors that affect the efficiency of the Geiger-Muller tube?
*the efficiency of the tube is defined as # of pulses counted per second/total flux entering the detector.
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Properties of the gas in a Geiger-Muller tube
Why does the gas filling a Geiger-Muller tube have to be inert and at low-pressure?
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Measure small mass change on heavy item [closed]
I need to measure the change in mass on a large number of components we are developing with a size of a large orange and weighing between 0.3 and 1 kg to an accuracy of sub 10x10-6 kg. The mass will ...
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In double-slit experiment with single atoms/molecules, how does the "gun" actually work?
In double-slit experiment with single atoms/molecules, how does the "gun" actually work?
How are the atoms/molecules "launched" to the slits?
user342647
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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 ...
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Experiments check out theories but who or what checks out the experiments? [closed]
There is a classic saying which goes more or less like this:
If your theory is not verified by the experiment then it is wrong!
Specifically for the field of particle physics, lately experiments ...
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Physics of cathode ray electroscopes: How to take the nonuniformity of the electric field between the deflection plates into account?
If you do deflection experiments using a cathode ray tube from a high school or college physics lab (like this), one usually gets a notable discrepancy between theory and experiment, if one assumes in ...
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Adjusting the trip current on a Bertan Model 1755
The Bertan Model 1755 is a high-voltage power supply that was used in many experiments at SLAC. As far as I can tell, it was manufactured specifically and exclusively for experiments at SLAC. The ...
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Are heavy or light nuclei used in the direct detection of dark matter?
My understanding is that recoils of light nuclei are easier to detect as they recoil with greater energy, however is the interaction cross section not much smaller, meaning interactions are much less ...
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What are the sealing adhesives for high vacuum system?
Recently, I have a project that needs to use a high vacuum system. During the construction process, I encountered a problem: I need to stick mica or glass to the window of the copper wall (one side is ...
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Deriving Wavelength from Relative Intensity with Broad Spectrum Light Sensor [closed]
I have this broad spectrum light sensor and it gives me readings in relative intensity, but says that it's able to measure the wavelength. The documentation is rather unhelpful, so I was wondering how ...
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How to make perpendicular surfaces without a reference surface?
Usually in machine shops, you measure perpendicularity with a reference surface. I am interested in how the perpendicular reference itself is created. Literarily the first one ever.
Is there a similar ...
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How do you stabilize the temperatures in your sensitive laboratory experiments?
I work in an AMO Lab, and I have been tasked with creating an experiment enclosure that will keep the air (and instruments) stable within about 50 mili-Kelvin with a set point of about 20C-21C. Our ...
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What contaminant materials should be avoided for reaching ultra-high vacuum? [closed]
This question relates to ultra-high vacuum chambers (order of ~$10^{-10}$ mbar) in experimental setups.
For this particular vacuum chamber, we have a set of ion pumps and a turbomolecular pump (...
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Which one is more precise: Phase locked loop or log the waveform then do sliding FFT?
I have an experimental confusion. I am using an interferometer to monitor the movement of a translation stage by monitoring the intensity of the coaxis interference pattern of the He-Ne laser.
...
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Comparison of beam divergence between laser diode and DPSS lasers
I'm currently comparing a pulsed laser diode and a pulsed DPSS laser. For the DPSS laser, the beam divergence is listed as "beam divergence (80% of total energy): $<4 \text{mr}$". The ...
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Realization of uniform volume charge density
A sphere with uniform volume charge density is often considered as an example in E&M. Is this a useful fiction for testing students or are there any techniques to induce a uniform volume charge ...
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Creating a map of energy from gravitation measurements
There are some devices which used supercooled falling atoms to measure gravity in order to weakly find large regions of different density.
Would it be possible with current technology to measure ...
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Is it necessary to use a collimated light beam when using a polarizer?
I am using two polarizers (one for an halogen light source and one for a camera) to measure light reflected in parallel and perpendicular polarization setups. Should the light source used along with ...
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Practical to measure topography of a large area (mm-scale) with scanning probe microscopy (SPM)?
I'm currently very new to nanotechnology. I do understand that it is possible to achieve an excellent topography image of a sample by SPM. However, is it possible to do SPM over a large area (for ...
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Experiment to determine the center of mass
Consider an axially symmetric rigid body with asymmetric mass distribution. Generally, the center of mass (and therefore moments of inertia) can be determined by knowing the center of mass of the ...
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How does loggerpro generate its uncertainty in position and time when conducting motion analysis at a given FPS and scale (e.g. metre ruler)?
I am conducting a physics experiment where I am trying to find the terminal velocity of a falling coffee filter by recording the drop on my phone at 4K 60 FPS and using the video to create a position ...
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How do non-mechanical solid-state optical switches work?
I am currently looking for a fiber-optical switch (FOS) in order to be able to change the light source of a spectrometer. As this will be used in harsh conditions, I was hoping to find a FOS with no ...
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The critical point of gold -- how did they measure this?
I was looking up something far more mundane and noticed this:
https://en.wikipedia.org/wiki/Critical_point_(thermodynamics)
...
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Mass of the fundamental particles
I have always wondered that how do scientists measure the mass of a fundamental particle.
Obviously they can't weigh it in a conventional machine we use to weigh other things in our daily life.
And do ...
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Is Thibado’s Graphene Brownian Capacitor Charger Perpetual Motion of the Second Kind?
In Fluctuation-induced current from freestanding graphene (peer-reviewed version on Phys. Rev. E, note: behind a paywall) Thiabado, et al, report the extraction of work from brownian motion. The ...
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Would a hypothetic very fast camera allow to visualize the variations of the amplitude of visible light?
The fastest camera available so far is capturing 10 millions images per second.
https://www.shimadzu.fr/hyper-vision-hpv-x2
In the scenario of the currently known physics, but in the hypothesis where ...
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What is the smallest time that the current technology can measure?
Many physical phenomena are associated with unbelievably small time scales. Let me give a few examples.
The time scale associated with visible light is $\sim$ a femtosecond ($10^{-15}$ sec),
The ...
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What are the properties of the Rice University self-assembling wires?
I've recently watched a video from Rice university, (https://www.youtube.com/watch?v=w1d0Lg6wuvc&t=3s) where they used an electric field to remotely stimulate CNTs to form a wire. This wire was ...
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How to produce light of a certain wavelength?
Is there a device which takes as input the wavelength or frequency value and produces electromagnetic waves of the given wavelength or frequency using an emitter? It might be that the wavelength range ...
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What piece of technology is able to record the exact phase of microwaves?
I read that in VLBI, the signals of microwaves are recorded and then later combined. A famous example of this is the Event Horizon Telescope which imaged the black hole. Presumably, the telescopes ...
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How can I create gamma rays with energy >2MeV?
I have been exploring pair production (electron/positron) using gamma, and with a Cobalt-60 source this is easy enough. That's just the problem, though.
I'm looking for a challenge. I want a stream ...
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How the relativistic mass gain prob is overcome in synchrotron by adjusting the frequency of electric field to accelerate particles to high KE?
Cyclotron cannot accelerate particles beyond certain KE due to relativistic mass gain. I am from Chemistry background.
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For experiments, how to ensure two photons arrive at beam splitter at the same time?
I'm working on work related DLCZ protocol. In DLCZ protocol, a beam splitter will be settled in the central of two ensembles (you can think it as light source). Ensembles will emit photons ...
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How is a spectrometer is calibrated for intensity?
For the case of spectrophotometers, we can easily calibrate the device(intensity wise) taking the light source inside the device as the reference, without any need of precise knowledge about its ...
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Relation among the dead time, recovery time and resolving time of a GM counter
I have been researching a lot for my assignment about the relation among the dead time, recovery time and resolving time of a GM counter. Most of the articles I came across have varying definitions on ...
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Why photodiode measures random phase superpositions on continuous-wave (10kHz) white light?
I measured a 10 kHz modulated white light using a photodiode (Thorlabs PDA10A):
Unexpectedly, the photodiode output sensitively depends on the orientation and position of the photodiode. For two ...
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What are the ways we have control over single photon emitters? Are there single photon emitters "on demand?"
I am wondering what are some of the ways we have been able to get more control over single photon emitters. What advances in technology have we made over the past years?
Is there anything that ...
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Do we need to know Earth's magnetic field locally?
I'm a high school student and in our course we have elements of earth's magnetic field (dip and other stuff) that lets us know the value and direction of magnetic field at any point on the planet.
I ...
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What is the most efficient single-photon detector to date?
(This question depends on the current time period, so the reader should make note and be aware of the date of the posted answers.)
I am wondering what is the most efficient state-of-the-art single-...
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How Do Scientists Measure Subatomic Particles? [closed]
I'm asking for a list of experiments, machinery, technology and techniques. The only measuring device I really know of is the Stern-Gerlach contraption. Google hasn't been helpful (it only gives me ...
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