Comments on: Reprieve for Fermilab; Whither ITER?

By: gopher65

gopher65 — Sat, 15 Nov 2008 22:23:38 +0000

abelian: I know someone who did that. Bought a van.

By: abelian

abelian — Fri, 04 Jul 2008 16:45:24 +0000

“With the money spend on Iraq one could build an ITER every 6 weeks or so”

That is equivalent to saying, ” I will stop smoking, save all that money and buy a car.” Theoretically possible, but in real life it never happens

By: Elliot

Elliot — Thu, 03 Jul 2008 16:23:52 +0000

So here is a (semi)-moral question to consider. You are a member of congress, maybe even representing IL or the district that encompasses Fermilab. You oppose the war but want the money back for the lab. How do you vote?

This is an example to me of a dysfunctional government when items are tied together in a package rather than considered individually.

I don’t know the right answer but would have a difficult time with this if I were in that situation.

By: Fermi-Walker Public Transport

Fermi-Walker Public Transport — Thu, 03 Jul 2008 15:08:36 +0000

With regards to the concerns about other countries seeing the U.S. as a reliable partner in projects, that horse has long left the barn. Think of the unilateral decision made about closing down the space station without informing its partners. I am not saying whether the decision was good or bad, just that it was unilateral.

By: Paul Schofield

Paul Schofield — Thu, 03 Jul 2008 12:14:33 +0000

To an extent, those neutrons are used to produce new fuel.

Tritium is produced through the forced fission of lithium when bombarded by neutrons. By surrounding the reactor with a layer of lithium, you can produce new tritium using the apparent waste products of the reaction.

Similarly, that energy that is removed from the reactor makes the plasma far easier to handle. If all the energy from the reaction had to be removed by conduction/transport alone then there would be no material I know of to stand up to the requirements.

The current pressing problems are materials development (which is a second, equally massive project going alongside ITER) and plasma stability. There are a number of issues that need to be resolved before fusion could possibly be sustained beyond a few seconds, but these things are being worked on and studied in current reactors.

So long as we can be sure that ITER won’t tear itself apart things should be good to go once it is built.

By: Tom

Tom — Thu, 03 Jul 2008 05:14:30 +0000

In reply to Lawrence,

Most of the energy goes into a neutral particle which would end up heating water to produce steam to run a turbine, which is the overall idea of a fusion reactor. Still, a significant amount of the energy produced in the fusion reaction results in a 3.5MeV alpha particle which deposits it’s energy back into the plasma, resulting in a self-sustaining burning plasma. Ideally, a plasma which exists for month-long shots, all the time producing 14 MeV neutrons (whose energy is used to power turbines) while only using D-T fuel pellets is certainly a reasonable energy source.

By: Ellipsis

Ellipsis — Thu, 03 Jul 2008 04:09:53 +0000

Flip — after your 5 billion dollar gift to FNAL, I’m confident things will work out just fine.

By: Flip

Flip — Thu, 03 Jul 2008 03:56:52 +0000

Hello — is there a danger that that America’s failure to live up to its ITER funding obligations will end up hurting Fermilab’s chances of landing the ILC?

By: Lawrence B. Crowell

Lawrence B. Crowell — Thu, 03 Jul 2008 02:20:25 +0000

I meant to say “off” the critical condition list.

By: Lawrence B. Crowell

Lawrence B. Crowell — Thu, 03 Jul 2008 02:18:50 +0000

Fusion research, including the ITER, I find problematic. The traditional D-T fusion results in about 80% of its energy in a neutron. This energy is effectively lost, for the neutral particle is hard to “catch.” This has always struck me as a huge fly in the ointment with the whole program. It strikes me as more energetically favorable to do

p + Li_7 — *Be_8 — 2He_4, * = unstable,

which involves a beam of protons on lithium in some state, such as a solid foil that the beam scans. I am aware of some problems with this, but at least all the energy is in charged alpha particles.

At any rate it looks as if HEP is critical condition list.

Lawrence B. Crowell