Narrow-width approximation

by Safinaz
Tags: approximation, narrowwidth
Safinaz is offline
Nov22-13, 03:11 AM
P: 36
Hi all,

I try to understand the difference which can made by using or not using NWA ..
I have a process have cross section (p p > x x) ~ 10^-5 pb , where x is a paricle have mass mx = 2 TeV
and dominant decay channel (x > b b~) with Gamma (x > b b~) ~ 6 * 10^2 GeV ,
while sigma ( p p > x x , x > b b~) ~ 10^-6 pb (I calculate this with a program not using the NWA)..

It's clear that if NWA is used sigma ( p p > x x , x > b b~) will just ~ 10^-5 pb since BR (x > b b~) =1,
so what does mean 10^-5 (NWA) and 10^-6 (non- NWA)

Is that what meant by that NWA has ## \Gamma/m ## approximation ?

Phys.Org News Partner Physics news on
Physicists design quantum switches which can be activated by single photons
'Dressed' laser aimed at clouds may be key to inducing rain, lightning
Higher-order nonlinear optical processes observed using the SACLA X-ray free-electron laser
RGevo is offline
Nov22-13, 12:04 PM
P: 81
Let me try to understand more.

Are you pair producing these two new particles? Then looking at the final state of 4 bs?

And your partial width of x>b bbar is 5% of the mass of x?
Safinaz is offline
Nov22-13, 02:09 PM
P: 36
I think I get it, thanks.

Register to reply

Related Discussions
Narrow Resonace of e+e- High Energy, Nuclear, Particle Physics 3
Narrow Width Approximation for a spin 1 resonance High Energy, Nuclear, Particle Physics 6
Approximation theory problem: show nonexistence of best approximation Calculus & Beyond Homework 0
born oppenheimer approximation vs adiabatic approximation Quantum Physics 4
How do I narrow my focus? Academic Guidance 3