Akatsu,%20M.
Max results
Sort by Reverse order

Showing 3 of 3 results

rivet Analysis
Measurement of the gamma gamma --> pi+ pi- and gamma gamma --> K+ K- processes at energies of 2.4-GeV - 4.1-GeV.

The Belle collaboration Nakazawa, H. ; Uehara, S. ; Abe, K. ; et al.
Phys.Lett.B 615 (2005) 39-49, 2005.
Inspire Record 667712 DOI 10.17182/hepdata.68395

We have measured pi+pi- and K+K- production in two-photon collisions using 87.7 /fb of data collected with the Belle detector at the asymmetric energy e+e- collider KEKB. The cross sections are measured to high precision in the two-photon center-of-mass energy (W) range between 2.4 GeV < W < 4.1 GeV and angular region |cos theta^{*}| < 0.6. The cross section ratio sigma(gammagamma->K+K-)/sigma(gammagamma->pi+pi-) is measured to be 0.89 +- 0.04(stat) +- 0.15(syst) in the range of 3.0 GeV < W < 4.1 GeV, where the ratio is energy independent. We observe a sin^{-4} theta^{*} behavior of the cross section in the same W range. Production of chi_{c0} and chi_{c2} mesons is observed in both gammagamma -> pi+pi- and gammagamma -> K+K- modes.

6 data tables
Table 1

Cross sections for PI+ PI- and K+ K- production.

Table 2

Ratio of K+ K- to PI+ PI- production in the region of W from 3.0 to 4.1 GeV, where the ratio is energy independent.

Table 3

Angular dependence of the normalized differential cross section, $\sigma_0^{-1}{\rm d}\sigma/{\rm d}|\cos\theta^*|$, for the $\pi^+\pi^-$ process. The errors are statistical only.

More…

rivet Analysis
Measurement of K^+K^- production in two-photon collisions in the resonant-mass region

The Belle collaboration Abe, Kazuo ; Abe, Koya ; Abe, T. ; et al.
Eur.Phys.J.C 32 (2003) 323-336, 2003.
Inspire Record 629334 DOI 10.17182/hepdata.50324

K^+K^- production in two-photon collisions has been studied using a large data sample of 67 fb^{-1} accumulated with the Belle detector at the KEKB asymmetric e^+e^- collider. We have measured the cross section for the process gamma gamma -> K^+ K^- for center-of-mass energies between 1.4 and 2.4 GeV, and found three new resonant structures in the energy region between 1.6 and 2.4 GeV. The angular differential cross sections have also been measured.

8 data tables
Table 1

Cross section for two photon production of K+ K- in the polar angular region ABS(COS(THETA*)) < 0.6.

Table 2

Differential cross sections DSIG/DCOS(THETA) for the W range 1.40 to 1.56 GeV.. Statistical errors only.

Table 3

Differential cross sections DSIG/DCOS(THETA) for the W range 1.56 to 1.72 GeV.. Statistical errors only.

More…

rivet Analysis
Measurement of inclusive production of neutral pions from Upsilon(4S) decays.

The Belle collaboration Abe, Kazuo ; Abe, K. ; Adachi, I. ; et al.
Phys.Rev.D 64 (2001) 072001, 2001.
Inspire Record 554520 DOI 10.17182/hepdata.31475

Using the Belle detector operating at the KEKB e+e- storage ring, we have measured the mean multiplicity and the momentum spectrum of neutral pions from the decays of the Upsilon(4S) resonance. We measure a mean of 4.70 +/- 0.04 +/- 0.22 neutral pions per Upsilon(4S) decay.

2 data tables
Table 1

No description provided.

Table 2

No description provided.