Experimental results in charmonium
Download
1 / 24

Experimental results in charmonium decays from BES - PowerPoint PPT Presentation


  • 102 Views
  • Uploaded on
  • Presentation posted in: General

Experimental results in charmonium decays from BES. Rong-Gang Ping (presented by F. Harris) for BES collaboration Charm 2007 Aug. 6, 2007. (2s) data samples. outline. ’ decays Leptonic decays Radiative decays Hadronic decays  cJ decays VV PPP. 26M. 14M. 4M. 3M.

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

Download Presentation

Experimental results in charmonium decays from BES

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


Experimental results in charmonium

decays from BES

Rong-Gang Ping

(presented by F. Harris)

for BES collaboration

Charm 2007

Aug. 6, 2007


(2s) data samples

outline

  • ’ decays

    • Leptonic decays

    • Radiative decays

    • Hadronic decays

  • cJ decays

    • VV

    • PPP

26M

14M

4M

3M

Also 6.42 pb-1 of data at Ecm=3.65 GeV

for background study.


Expected? Sequential lepton hypothesis:


  • BESII: remeasure with larger sample

  • Measured in     ee

  • Characterized by

    • 2 charged tracks; 1  and 1 e

    • missing energy and momentum

    • no extra hits in BSC

 = 17.8%


BESII   

Result:

B(  ) =

(3.100.210.38) x 10-3

Lepton universality is tested in charmonium decays.

PRD 74: 112003 (2006)


’ radiative decays PRL 99, 011802 (2007)


Observation of ’ radiative decays

  • Expect ~1% BR, but only 0.05% previously observed.

  • Potential channels for hadron spectroscopy study, including search for non-qqbar states, if enough statistics.

  • ~ 0.1% more observed in this analysis.

PRL99, 011802 (2007)


PRD74, 072001 (2006).


PRD74, 072001 (2006).


MARK-II

K*K

ρπ


x 10-4

x 10-4

Angular distribution:

2


Baryonic decays

Rich structure (N*s), statistics (~850 evts in each mode). Still low for a partial wave analysis.

PRD74, 012004 (2006)


Test I-spin symmetry

(prediction: 1:2:2)


PRL 99,011802 (2007)


Pair production of vectors

PLB642, 197 (2006)

c0

c1

c2

Improved precision over PDG (BESI) results on cJKKKK and .

First measurement of cJKK.

cJ→2(K+K)


c1

c2

cJ decays into PPP

PRD74, 072001 (2006)

cJ→KK and 

c1→KSK+-+c.c.

K*

PRD 74, 072001 (2006)

c0→PPP is suppressed

by spin-parity selection;


Nsig=418± 60

h

c1→ +-

Nsig=222±28 (8.8s)

Nsig=58± 14 (4.5s)

h sideband

a0 sideband


BES: cJ→KK and  PRD 74, 072001 (2006)

CLEO-c, PRD75, 032002


arXiv: 0707.1127 [hep-ex]

Submitted to PRD

’(J/) +0/

  • Is it really B(0)>B()?

background from

J/  ΣΛπ

signal

First measurement!


Summary

  • ’ leptonic decays, hadronic decays, radiative decays are studied to search for new phenomena and to test QCD predictions.

  • c decays are studied using ’ data sample.

  • CLEOc will take the leading role in ’ and c decays; we are now preparing for the BESIII data taking and the physics analysis.

Thanks a lot !


ad
  • Login