Zhi yong zhou southeast university
Download
1 / 27

Rescattering effect in understanding D decay processes - PowerPoint PPT Presentation


  • 89 Views
  • Uploaded on

周智勇 东南大学. Zhi -Yong Zhou Southeast university. Rescattering effect in understanding D decay processes. 2013.7.20 Zhangjiajie. How to precisely model the final state strong interaction is important to understand the weak interactions in shorter distance.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Rescattering effect in understanding D decay processes' - jaeger


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Zhi yong zhou southeast university

周智勇

东南大学

Zhi-Yong Zhou

Southeast university

Rescattering effect in understanding D decay processes

2013.7.20

Zhangjiajie


Motivation

Motivation


Rescattering
Rescattering important to understand the weak interactions in shorter distance.

In calculation of Dyson-Schwinger equation, the propagator of the ρ-meson expressed in terms of quark line graphs. At lowest order it is assumed to be a meson, which decays at higher order by coupling to pion pairs.


The analytic structure of the ρ-propagator in the complex s-plane. At lowest order, the propagator is real with a pole on the real axis corresponding to a bare meson. The corrections at higher orders, dominated by pion loops, give the full propagator with a pole on the nearby unphysical sheet.


A simple scheme

Start by considering a simple model at the s-plane. At lowest order, the propagator is real with a pole on the real axis corresponding to a bare meson. The corrections at higher orders, dominated by hadron level, in which the inverse meson propagator could be represented as

Πn(s) is the self-energy function for the n-th decay channel. Here, the sum is over all the opened channels or including nearby virtual channels. Πn(s) is an analytic function with only a right-hand cut starting from the n-th threshold, and so one can write its real part and imaginary part through a dispersion relation

A Simple Scheme


Based on s-plane. At lowest order, the propagator is real with a pole on the real axis corresponding to a bare meson. The corrections at higher orders, dominated by Cutkosky rule, the imaginary part of the self-energy function could be represented pictorially as


Progress in understanding light scalars

1, Most of states below 2.0 s-plane. At lowest order, the propagator is real with a pole on the real axis corresponding to a bare meson. The corrections at higher orders, dominated by GeV could be described in a consistent and unified picture.

Progress in understanding light scalars

Z.Zhou and Z.Xiao, Phys.Rev.D83,014010,2011


Progress in understanding mesons with charm quarks

  • The masses of charmed and charmed-strange mesons s-plane. At lowest order, the propagator is real with a pole on the real axis corresponding to a bare meson. The corrections at higher orders, dominated by and their decays could be described simultaneously.

  • The low mass puzzle of is solved naturally in this scheme.

  • In a prilliminary work, we obtained good results about charmonium spectra and their decays, which is consistent to the observed values in experiment.

Progress in understanding mesons with charm quarks

Z.Zhou and Z.Xiao, Phys.Rev.D84,034023,2011


Z.Zhou s-plane. At lowest order, the propagator is real with a pole on the real axis corresponding to a bare meson. The corrections at higher orders, dominated by and Z.Xiao, Phys.Rev.D84,034023,2011


Rescattering s-plane. At lowest order, the propagator is real with a pole on the real axis corresponding to a bare meson. The corrections at higher orders, dominated by effects in Decay process

isobar picture


Unitarity for P s-plane. At lowest order, the propagator is real with a pole on the real axis corresponding to a bare meson. The corrections at higher orders, dominated by  (c)

Or see Aitchson 1977, Caprini 2006, Pennington 2006


K s-plane. At lowest order, the propagator is real with a pole on the real axis corresponding to a bare meson. The corrections at higher orders, dominated by

1 - iK

T =

P

1 - iK

= T

F =

coupling function

UNITARITY : decays in spectator picture

If c is not a spectator?


Brian Meadows s-plane. At lowest order, the propagator is real with a pole on the real axis corresponding to a bare meson. The corrections at higher orders, dominated by


1200 s-plane. At lowest order, the propagator is real with a pole on the real axis corresponding to a bare meson. The corrections at higher orders, dominated by

1000

800

Events/0.04(GeV/c2)2

600

400

200

0

0

0.5

1

1.5

2

2.5

3

m2(K-+low) (GeV/c2)2

600

500

400

Events/0.04(GeV/c2)2

300

200

100

non-resonant dominates

0

0

0.5

1

1.5

2

2.5

3

m2(K-+high) (GeV/c2)2

Brian Meadows


1200 s-plane. At lowest order, the propagator is real with a pole on the real axis corresponding to a bare meson. The corrections at higher orders, dominated by

1000

800

Events/0.04(GeV/c2)2

600

400

200

0

0

0.5

1

1.5

2

2.5

3

m2(K-+low) (GeV/c2)2

600

500

400

Events/0.04(GeV/c2)2

300

200

100

0

0

0.5

1

1.5

2

2.5

3

m2(K-+high) (GeV/c2)2

Brian Meadows


Brian Meadows s-plane. At lowest order, the propagator is real with a pole on the real axis corresponding to a bare meson. The corrections at higher orders, dominated by


E791 s-plane. At lowest order, the propagator is real with a pole on the real axis corresponding to a bare meson. The corrections at higher orders, dominated by vselastic scattering (LASS)

LASS

phases (degrees)

E791

M (K) GeV


Rescattering s-plane. At lowest order, the propagator is real with a pole on the real axis corresponding to a bare meson. The corrections at higher orders, dominated by


Rescattering : Unitarity s-plane. At lowest order, the propagator is real with a pole on the real axis corresponding to a bare meson. The corrections at higher orders, dominated by

Watson’s theorem

elastic

phases simply related

if no rescattering


Rescattering : Unitarity s-plane. At lowest order, the propagator is real with a pole on the real axis corresponding to a bare meson. The corrections at higher orders, dominated by

Including rescattering effect


Discontinuity relation of decay amplitude: s-plane. At lowest order, the propagator is real with a pole on the real axis corresponding to a bare meson. The corrections at higher orders, dominated by

After making a partial wave projection,

Write it in short,


Pictorially represented as s-plane. At lowest order, the propagator is real with a pole on the real axis corresponding to a bare meson. The corrections at higher orders, dominated by

Elastic region

Inelastic region

Unitarity requires four points on Argond diagram, t*, a + h, (0, 1) and (0, Im[a]), stay on a circle.


Reproduced K\pi scattering phase by E791 result s-plane. At lowest order, the propagator is real with a pole on the real axis corresponding to a bare meson. The corrections at higher orders, dominated by


Q:Whether there is the phase ambiguity of ? s-plane. At lowest order, the propagator is real with a pole on the real axis corresponding to a bare meson. The corrections at higher orders, dominated by

A: Perhaps yes.


How to obtain a better s-plane. At lowest order, the propagator is real with a pole on the real axis corresponding to a bare meson. The corrections at higher orders, dominated by Dalitzanalysis for the processes with strong final state interaction?

Building the following relations into analyses may help.


Thanks for your patience
Thanks for your patience! s-plane. At lowest order, the propagator is real with a pole on the real axis corresponding to a bare meson. The corrections at higher orders, dominated by


ad