Why Deuterium/Anti-deuterium?

[Christopher]

The distance pions, muons, etc can travel before decaying depends on their speed too. If you don't accelerate them quickly, they don't travel far. If you accelerate them to relativistic speeds, they can travel very far. Your numbers (at least for pions) are for relativistic speeds.

Yup, not only because faster particles can cover more distance in the same amount of time, but because particles at relativistic speeds are time-dilated and decay more slowly as measured by an observer at relative rest.

 

[feld]

Your numbers (at least for pions) are for relativistic speeds.

Yes. Why is that relevant?

I believe that the pions are expected to achieve those velocities if they are created as the products of an annihiliation reaction. The tough part would be slowing the little buggers *down*. They're born relativistic from the annihiliation.

If I'm wrong on this and you can prove it I'd really like to know because it means I've missed something really big.

My distances are from pg 4 of a 2003 paper by Dr. Robert Frisbee entitled "Robert H. Frisbee, “How to Build an Antimatter Rocket for Interstellar Missions”, AIAA-2003-4676" which assumed that the particles were formed as reaction products from the annihilitation of protons and anti-protons. Though he actually appears to have pulled the figures from an older paper by Dr. Robert Forward to which I have no access at present. This one:


Forward, R.L., “Antiproton Annihilation Propulsion,” AIAA Paper AIAA-84-1482, Presented at the AIAA/SAE/ASME 20th Joint Propulsion Conference, Cincinnati OH, June 11-13, 1984

I admit that I've not checked their math myself...but I'm too far out of my college quantum courses to do it. I've been taking the Docs' word for it.
v/r
feld

 

[LazyReader]

It's 90% of available standard mass of the universe....

• widely abundant
• inexpensive
• good feedstock
• make water
• used in fusion first so industrial infrastructure already exists

 

[CorporalCaptain]

It's 90% of available standard mass of the universe....

Nope.

 

[publiusr]

I might want plutonium and anti-plutonium...denser that way.

 

[StarCruiser]

Wow... 9 1/2 year old dead thread...really?

 

[Unicron]

As a general rule, I'm cautious about threads this old being resurrected. But since it's almost always done by newer members who don't want to cause a problem, I'll allow it if leads to renewed discussion. If not, the thread will usually go back to sleep so it's not a huge problem.