Photon induced magnetic effects

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hagopbul
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About HB-11 tests
Hello all:

Reading about HB-11 start up and they mentioned laser induced magnetic field :

How is that created and the size of the magnetic field is in kilo Tesla range anyone heard of that

Best
Hagop
 
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Can't be sure of the specifics, but I suspect it may be referring to the transverse magnetic field that makes up the electromagnetic wave that is the laser. A beam of light consists of a tranverse electric (E) and magnetic (B) field, and although the magnitude is typically described in terms of the E field, the magnitude of the B field (in a vacuumlike medium) is just E/c where c is light speed.

The intensity (power per unit area) of an electromagnetic wave is cB^2/( 2 mu), where mu is the magnetic constant and B refers to the peak amplitude of the magnetic field (not its RMS value or whatever). A 10 milliwatt laser pointer focused to a square centimeter has a peak field of like a microtesla, whereas with optical tweezers 1-watt laser can be focused to a square micron, which corresponds to about 0.1 tesla, comparable to a strong permanent magnet.

The most powerful laser in the world at the National Ignition Facility deposits something 500 terawatts onto a square millimeter target, which is like 2000 Tesla. Sounds in range of what this HB-11 is doing.
 
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klotza said:
A 10 milliwatt laser pointer focused to a square centimeter has a peak field of like a microtesla, whereas with optical tweezers 1-watt laser can be focused to a square micron, which corresponds to about 0.1 tesla, comparable to a strong permanent magnet.

Then it is referring to the light magnetic fields not something related to material - laser interaction?
 
hagopbul said:
Reading about HB-11 start up and they mentioned laser induced magnetic field :

How is that created and the size of the magnetic field is in kilo Tesla range anyone heard of that

Maybe, your question might be related to Fig. 3 in the paper "Laser boron fusion reactor with picosecond petawatt block ignition": https://arxiv.org/abs/1708.09722
 
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It is sad when people who are responding to this thread are the ones doing and searching for the background sources for the OP. You guys are simply guessing what the OP meant, when the burden of showing the sources should have been on the OP.

Do not encourage laziness!

Zz.
 
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In principle, you are completely right. However, there was no guessing involved as I know that HB11 stands for fusion of hydrogen with the boron Isotope 11 - a candidate for aneutronic fusion.
 
ZapperZ said:
You guys are simply guessing what the OP meant, when the burden of showing the sources should have been on the OP.

Part of the issue is that he started two threads on this, and some of the information is in the other thread.

That's not the entire issue, of course, but it's part of it for sure.
 
Guys I couldn't find any thing on the internet regarding what methods they are using to create such a magnetic field , that why I asked about it here it was unclear for me , the amount of the magnetic field generated is really large

I always come to here when it is difficult to find it in the internet
 
Even with paper that thankfully provided by LJ there is no indication of how the laser is converted to magnetic field.
 
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