funsec mailing list archives
Re: Fun with (In)Security
From: Drsolly <drsollyp () drsolly com>
Date: Mon, 30 Jan 2006 15:36:18 +0000 (GMT)
On Mon, 30 Jan 2006 Valdis.Kletnieks () vt edu wrote:
On Mon, 30 Jan 2006 11:19:28 GMT, Drsolly said:You get a gun (that's a real gun, not the popguns that it's legal to buy, something in 88mm or so) and fire one piece at the other; that's how Little Boy worked. I don't think it's rocket science.Actually, it's trickier than it looks - the "obvious" solution of simply slamming two sub-critical hemispheres together will almost certainly fizzle. The problem is that as it gets close, the surfaces start to melt down and vaporize, and the resulting high-pressure vapor tends to push the pieces apart before you get a really good chain reaction going. And if you want to get good efficiency, the projectile part is riding the pressure wave of some really high energy explosives to compress the fissionable material. Yes, it's metal, but a really good shaped charge can compress metal by a factor of 3 to 5 or more, which makes the reaction go *lots* faster by reducing the average neutron travel distance (and hey, that explosive only has to keep it compressed for a few ten-thousandths of a second). Oh, and you want to try really hard to make the compression symmetric, as otherwise the more dense side will start to fission first, and blow itself apart before the other side gets going, resulting in a fizzle or a low yield.... Of course, there's not much real difference between a dirty bomb and a fizzle, so if you're a terrorist you can just bang two hemispheres together... :)
It's like programming. Version 1 tells you what you need to do to make a good version 2. _______________________________________________ Fun and Misc security discussion for OT posts. https://linuxbox.org/cgi-bin/mailman/listinfo/funsec Note: funsec is a public and open mailing list.
Current thread:
- Re: Fun with (In)Security, (continued)
- Re: Fun with (In)Security Drsolly (Jan 28)
- Re: Fun with (In)Security David Lodge (Jan 29)
- Re: Fun with (In)Security TheGesus (Jan 28)
- RE: Fun with (In)Security William Lefkovics (Jan 29)
- Re: Fun with (In)Security Fergie (Jan 28)
- Re: Fun with (In)Security Paul Schmehl (Jan 28)
- Re: Fun with (In)Security Technocrat (Jan 29)
- Re: Fun with (In)Security Valdis . Kletnieks (Jan 29)
- Re: Fun with (In)Security Drsolly (Jan 30)
- Re: Fun with (In)Security Valdis . Kletnieks (Jan 30)
- Re: Fun with (In)Security Drsolly (Jan 30)
- Re: Fun with (In)Security Rob, grandpa of Ryan, Trevor, Devon & Hannah (Jan 30)
- Re: Fun with (In)Security Paul Schmehl (Jan 28)