I Pressures required for nuclear fusion

[g_mogni]

I know that to achieve fusion one has to satisfy the Lawson criterion. My question is: can fusion be achieved only by generating very high pressures but keeping the system at room temperature, or does it necessarily require a combination of both high pressures and high temperatures? If by some miraculous design one could apply a pressure of 1 Million Megabars to a tiny volume of D-T gas, would that be enough or are temperatures of millions of degrees also required? I can't find anywhere the data for the D-T reaction cross-section as a function of pressure but at room temperature...

Thanks,

Gabriele

 

[mfb]

I know that to achieve fusion one has to satisfy the Lawson criterion.

Only for self-sufficient fusion without continuous heating. But you have to get at least close to it to get relevant fusion.

There is no realistic way to get a high pressure without a high temperature on any reasonable timescale, but eventually you'll get fusion even in that case.

 

[mathman]

Laser fusion uses extremely high pressure, without any particular heating.

 

[mfb]

The compression still heats up the fuel.

 

[mathman]

The compression still heats up the fuel.

You are right. The point I was trying to make is that the fuel is not heated for the fusion to take place. The compression is the main mechanism.

 

[g_mogni]

Thank you for you replies. I therefore understand that high-temperatures are not a pre-requisite for fusion to take place, high-pressures alone can be enough, but often high temperatures are a by-product of the high-pressure compression due to the way the fuel capsule behaves and its equation of state...

G

 

[snorkack]

When ideal gas is adiabatically compressed, the ratio of final and initial temperature is determined by the compression ratio, and independent of the initial temperature.

What happens when a solid is adiabatically compressed?