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Questions tagged [free-electron-lasers]

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When a laser pulse rate is stated, does that include the time that it is off? If pulse rate is 1,000 per second, is it on for half a millisecond?

Sorry if this seems a stupid question to some, but I am having trouble finding a consistent answer.... The European XFEL hard X-ray headline proudly states that it is currently the fastest of its kind ...
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What is meant by "low-lying" electronic states?

In the context of electronic structure and spectroscopy, the term "low-lying electronic states" is quite common but it really isn't defined anywhere. All google search results lead to ...
PestoPotato's user avatar
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Does a low-gain free electron laser (FEL) emit coherent radiation?

For the low-gain free electron laser (FEL), an external field is injected into an undulator alongside an electron bunch. Due to phase slippage (because the light is faster than the electrons) the ...
Liberty's user avatar
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Rhodium based gamma-laser

Has anyone considered using the excited meta-state of Rh 102 to create a gamma-ray laser?. I see an advantage in favor of using Rh 102m extracted from nuclear waste over Hf 178m2. While Rh 102m has a ...
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What is the difference between an undulator and a free-electron laser (FEL)?

I am very confused by the graphic below: In particular, why are undulators and FEL separated? Furthermore, I do not quite understand how the intensity values come to be: Wiggler: Every electron ...
Fabian Schn.'s user avatar
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Why is the opening angle of synchrotron radiation less than $1/\gamma$?

I am currently studying free-electron laser which accelerate electrons and use undulators to create synchrotron radiation. In a variety of graphics and diagrams I see an opening angle of $\pm 1/\gamma$...
Fabian Schn.'s user avatar
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Laser book for physics GRE

The recent physics GRE exams have some questions on lasers. Does anyone know of a good book which goes briefly through different types of lasers?
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The physics behind European XFEL

I tried to find detailed data at the official site and learned that the linear accelerator is 1.7 Km long, the energy of the electrons is 17.5 GeV (35000$\times$ the electron rest energy), and the ...
user157860's user avatar
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What makes the European XFEL the "fastest laser in the world"?

I'm working in Hamburg so listening this morning to the local radio channels, all had been reporting about the "greeting call" to DESY by different organizations pointing with their lasers to the ...
Zaibis's user avatar
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How does self-amplified spontaneous emission (SASE) work?

Due to the new laser in Hamburg, the XFEL, the following question arised: How does self-amplified spontaneous emission (SASE) work? There is an official article here http://www.xfel.eu/overview/...
Ben's user avatar
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A question regarding pump-probe processes

As the following figure illustrated,the pump-probe processes contain mainly two steps: Pump pulse drives the sample out of equilibrium (red line); Time evolution measured by subsequent probe pulses; ...
Jack's user avatar
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free electron laser. Reference?

Where can I find a comparison graph of the peak power of free electron lasers and synchrotrons ?
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Do free-electron lasers actually lase?

Free-electron lasers are devices which use the motion of highly energetic electron beams to produce bright, coherent radiation in the x-ray regime. More specifically, they start with a high-energy ...
Emilio Pisanty's user avatar