Narrow-width approximation


by Safinaz
Tags: approximation, narrowwidth
Safinaz
Safinaz is offline
#1
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 ?

Regards,
Safinaz
Phys.Org News Partner Physics news on Phys.org
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
RGevo is offline
#2
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
Safinaz is offline
#3
Nov22-13, 02:09 PM
P: 36
Hi,
I think I get it, thanks.
S.


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