High-statistics study of neutral-pion pair production in two-photon collisions

S. Uehara et al. (Belle Collaboration)
Phys. Rev. D 79, 052009 – Published 25 March 2009

Abstract

The differential cross sections for the process γγπ0π0 have been measured in the kinematic range 0.6GeV<W<4.1GeV, |cosθ*|<0.8 in energy and pion scattering angle, respectively, in the γγ center-of-mass system. The results are based on a 223fb1 data sample collected with the Belle detector at the KEKB e+e collider. The differential cross sections are fitted in the energy region 1.7GeV<W<2.5GeV to confirm the two-photon production of two pions in the G wave. In the higher-energy region, we observe production of the χc0 charmonium state and obtain the product of its two-photon decay width and branching fraction to π0π0. We also compare the observed angular dependence and ratios of cross sections for neutral-pion and charged-pion pair production to QCD models. The energy and angular dependence above 3.1 GeV are compatible with those measured in the π+π channel, and in addition we find that the cross section ratio, σ(π0π0)/σ(π+π), is 0.32±0.03±0.05 on average in the 3.1–4.1 GeV region.

  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
3 More
  • Received 22 January 2009

DOI:https://doi.org/10.1103/PhysRevD.79.052009

©2009 American Physical Society

Authors & Affiliations

Click to Expand

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 79, Iss. 5 — 1 March 2009

Reuse & Permissions
Access Options
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review D

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×