Message: Re: BERT vs. BIC physics lists Not Logged In (login)
 Next-in-Thread Next-in-Thread
 Next-in-Forum Next-in-Forum

None Re: BERT vs. BIC physics lists 

Forum: Physics List
Re: Question BERT vs. BIC physics lists (Dipak Rimal)
Date: 19 Nov, 2014
From: Tom Roberts <Tom Roberts>

On Wed, 19 Nov 2014 07:00:05 GMT, Dipak Rimal wrote:
> I also have a question about pi^-/mu^- capture at rest process. In our
> simulation, almost all of the produced pi^-/mu^- are being captured,
> none of them decay (at rest), less than 0.5 % decay in flight. This
> sounds a bit odd to me. Any comments?

If your target is large enough that most pi- and mu- stop, then this makes sense. Almost all negative particles that stop in a material get captured very quickly (few femtoseconds IIRC), especially for high-Z materials. Speaking loosely, that's because inside each atom the electrons do not fully screen the nuclear charge, so there is a strong E field that captures negative particles with low enough kinetic energy. While stopping, every particle will have low enough KE to be captured, so inside a material the only decays in flight of negative particles are those that decay before they stop.

Note also that once captured, the negative muon has effectively a shorter decay lifetime than a free muon. This is a function of the Z of the nucleus, and can be a large factor for high-Z nuclei like Hg.

Inline Depth:
 1 1
 All All
Outline Depth:
 1 1
 2 2
 All All
Add message: (add)

1 None: Re: BERT vs. BIC physics lists   (Dipak Rimal - 24 Nov, 2014)
 Add Message Add Message
to: "Re: BERT vs. BIC physics lists"

 Subscribe Subscribe

This site runs SLAC HyperNews version 1.11-slac-98, derived from the original HyperNews


[ Geant 4 Home | Geant 4 HyperNews | Search | Request New Forum | Feedback ]