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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1answer
348 views

Is there a significant possibility of the LHC missing “exotic” particles or events?

In his popsci book, "Particle at the end of the universe", Sean Carroll says that the LHC, due to it's sheer information gathering capability, necessarily needs to completely discard most of the data ...
3
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0answers
35 views

Energy dependence of integrating dosimeters

The graph shows the relative response of a dosimeter at different energies, normalized to 1.25 MeV Co-60 gamma rays. Curve A is the graph of the equation $$ ...
3
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1answer
53 views

What are the purposes of slits inside a spectrometer (Czerny-Turner)?

I am building a Raman spectrometer with a Czerny Turner configuration (with RamanPi). Why does the light source (A) appear to be converging into the entrance slit (B)? When a sample is excited by ...
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0answers
53 views

Making a bright beam of artificial white light

For educational purposes, is there a way to make a narrow bright beam of white light without much equipment and without using the sun as the source? The collimated beam should be about 2 mm wide for ...
1
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2answers
54 views

What is the best thermal heatsink compound?

Re-worded This is about the Experimental Physics not PC building or how to grease a car's radiator. I have to insert a stainless steel enclosed PT100 into a block of metal to monitor its temperature ...
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0answers
14 views

Given temp and conductivity can I back-calculate to resistance, in order to plug in a new temp value and calculate a more accurate conductivity?

Background: I used a small CTD (conductivity, temperature, depth) recorder to log a series of dive profiles in a mixed coastal estuary. The recorder logged observed temperature and conductivity every ...
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1answer
88 views

Measuring depth or height from sea level

How is the depth or height relative to sea level measured? Well, if it's near the ocean, it can be easily measured manually, but what if it is 100 km away from the sea? What method is used?
3
votes
1answer
116 views

Low-cost 532nm DPSS laser modulation

Could anyone suggest modern means of modulating 100mW CW 532nm DPSS laser? This should be low-cost(<50$) in high volume. Frequency bandwidth is 10Mhz, so modulation of pumping diode would ...
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0answers
24 views

How big can be gradient of magnetic induction (in lab)

I'm thinking about magnetic levitation and how big force can push a diamagnetic when we put it in inhomogenious magnetic field. As far as I know, force exerted on a diamagnetic is proportionald to ...
3
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0answers
48 views

Entanglement g-2-experiment - Which components do I need?

I would like to measure whether my source emits entangled photon pairs. To that order I want to build a g-2-experiment, which measures photon coincidence counts as a function of time delay between ...
1
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1answer
37 views

What is the easiest way to demonstrate low magnetic flux NMR on the bench?

I'm trying to build my own low fux density bench NMR set-up, and am well-versed in electronics. Continuous Wave is supposed to be the easiest. I see commercial instruments that stimulate elements in ...
6
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1answer
162 views

How can I make a dry dilution refrigerator quiet?

The pulse tubes are really loud. We've wrapped the helium lines in sound absorbing foam, and we have a cage around the top of the cryostat also lined with foam, but it's still pretty loud. To make ...
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0answers
29 views

Quantum Efficiency Estimation

Might there be a way to do a rough estimate of the quantum efficiency of a photo-detector like a CCD or CMOS sensor based only on a picture taken with it? I've read papers and guides (like this one: ...
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0answers
41 views

Any photon colliders in the past?

People have been thinking about a photon-photon collider (see this and this) as an add-on or to supplement the ILC, the next generation linear collider. My question is, have there been any ...
0
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1answer
217 views

Scanning Electron Microscopy: Explanation of Numerical aperture and Extraction Field

I am trying to understand what numerical aperture and extraction field means in a scanning electron microscope. From what I understand numerical aperture is used to set the Depth of Focus which is ...
1
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1answer
1k views

holographic projection in thin air? [duplicate]

from where I come from ,they taught us in high school that it is possible to project holograms in thin air simply by illuminating the hologram with the "correct light" , and having a semi transparent ...
4
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2answers
200 views

Catching/harvesting neutrons

This question has several parts. How does modern science catch free neutrons that are just floating around? Is there anyway to "pull" a neutron off any atom that does not involve our current ...
1
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1answer
94 views

Conductive glue

I would like to use some conductive glue to contact a silicon chip's back gate. Any suggestions on what to use? Can I use thermal silver paste? I would be operating at cryogenic temperatures below 4K. ...
0
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1answer
221 views

How long does it take to scan a typical scanning electron microscope image?

I suppose the answer depends on resolution and imaging area, but can you provide some ball park measures of imaging times with an SEM?
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3answers
113 views

Do nanoscopes exist?

We are mostly all familiar with a microscope, and know that it helps to see MICRO components, like stuff that is photolithographically etched on silicon semiconductor die. (The latter can also be ...
1
vote
1answer
46 views

How sodium atoms in lamp are energized to produce light?

In a recent spectroscopy lab I performed for one of my classes we used a Lambda Scientific LLE-1/2 mercury/sodium lamp (to look at the sodium doublet) and a Lambda Scientific LLE-8 hydrogen/deuterium ...
5
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1answer
550 views

Are CCDs approaching the sensitivity of photomultiplier tubes?

I still see photomultiplier tubes (PMT) used for even benchtop spectroscopy experiments. How much more sensitive are they to CCDs? I found a post which claims about 1.5 x more sensitivity for ...
10
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2answers
1k views

Methods to stabilize and maintain extremely low humidity in a lab environment

My atomic physics lab is in a building that experiences huge swings in humidity levels during the year due to the monsoon season Our building provides temperature, but not humidity control. Using ...
4
votes
1answer
230 views

How can some optical microscopes measure height differences of different sample planes with nanometer accuracy?

I could use last week an optical microscope, didn't seem special in any way, 50x magnification, image viewable per a CCD camera on a computer screen besides through the ocular. But the software of ...
3
votes
2answers
304 views

Layman's method to sharpen a wire (STM-tip)

We use a platinum-irididum wire to fabricate our STM tips. And by "fabricate" I mean to cut it with really sharp pliers or scissors. Sometimes we get good tips but most of the time they are not usable ...
6
votes
1answer
74 views

How strong must a signal be at the edge of the Solar System to penetrate into the Sytem?

A sort-of follow-up to Are the Voyager probes still sending us a signal ? Still following on the news report referenced in the above question, this report indicates further magnetic surprises at, or ...
5
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0answers
270 views

Mirrors and light beam divergence technology limits

There are many applications for orbital space mirrors in astronomy (better telescopes) and space propulsion (solar power for deep space probes), but this is limited by the minimum beam divergence ...
2
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0answers
57 views

Improvements on a makeshift dessicator

I am a first year undergrad working in a lab, and I have these Plexiglass containers that I tried to convert to dessicators, since the commercial bell jars are really expensive. I used these weather ...
4
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2answers
2k views

Could we use particle colliders as fusion generators?

So I know the basic gist is that fusion power's main issue is sustaining the fusion. I also know that there are two methods. The Torus method and the laser method. The torus magnetically contains ...
14
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3answers
206 views

Why and how will we be able to image extraterrestrial planets in the next two decades?

According to a recently published article, a well-established Cambridge astrophysicist stated that: the ÔÇťorigin of life, where it exists, and whether aliens exist, is going to be crucial over ...
0
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1answer
94 views

Future of colliders and technical limitations

Are there any technical limitations (theoretical or technological) that prevent quark based colliders? ie. Colliding two quarks together.
4
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1answer
144 views

Are old fashion photomultipliers used in LHC experiments?

Are any photomultipliers used in any of LHC detectors? Or are only semiconductor devices used? If yes, then where?
5
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1answer
357 views

How does the Double Slit Experiment work in detail?

What is the best detailed description/visualisation of the experiment available? Describing what is actually measured, how the data is analysed, correlated and interpreted when for example large ...
2
votes
1answer
1k views

Inductor with controlled temperature coefficient

Let's assume we have an air-spaced inductor made of copper wire. As temperature changes, due to thermal expansion of physical dimensions of the coil, its inductance changes too. 1) Is there a way to ...
5
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2answers
324 views

Accuracy of various optical instruments

I understand that this may not be the type of question allowed here, but I'm not sure. Feel free to close this if you feel that it shouldn't be here I'm planning on carrying out a certain set of ...
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1answer
184 views

Light filter for an experiment

I'm looking for a filter that lets through as many wavelengths as possible (from 200 to 5000 nm). Is that even possible?
14
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1answer
419 views

Are the Voyager probes still sending us a signal ?

This article reported today, a finding from one of the voyager probes. It talks about magnetic structures at the (far) outer edge of our solar system. Does that mean we're still able to pick up a ...