Measurement of the near-threshold $e^+e^- \to D^{(*)\pm}{D}{}^{*\mp}$ cross section using initial-state radiation

The Belle collaboration Abe, Kazuo ; Adachi, I. ; Aihara, H. ; et al.
Phys.Rev.Lett. 98 (2007) 092001, 2007.
Inspire Record 723333 DOI 10.17182/hepdata.19336

We report a measurement of the exclusive $e^+e^- \to D^{(*)\pm}{D}{}^{*\mp}$ cross section as a function of center-of-mass energy near the $D^{(*)^{\pm}}{D}{}^{*\mp}$ threshold with initial state radiation. A partial reconstruction technique is used to increase the efficiency and to suppress background. The analysis is based on a data sample collected with the Belle detector at the $\Upsilon(4S)$ resonance and nearby continuum with an integrated luminosity of 547.8 $\mathrm{fb}^{-1}$ at the KEKB asymmetric-energy $e^+ e^-$ collider.

2 data tables

Cross section for E+ E- --> D*+ D*-.

Cross section for E+ E- --> D+ D*- (plus charged conjugate).


Measurement of gamma gamma --> p anti-p production at Belle.

The Belle collaboration Kuo, C.C. ; Abe, K. ; Adachi, I. ; et al.
Phys.Lett.B 621 (2005) 41-55, 2005.
Inspire Record 677625 DOI 10.17182/hepdata.50303

A high precision study of the process gamma gamma -> p p-bar has been performed using a data sample of 89/fb collected with the Belle detector at the KEKB e+e- collider. The cross section of p p-bar production has been measured at two-photon center-of-mass (c.m.) energies between 2.025 and 4.0 GeV and in the c.m. angular range of |cos(theta^*)|<0.6. Production of gamma gamma -> eta_c -> p p-bar is observed and the product of the two-photon width of the eta_c and its branching ratio to p p-bar is determined.

6 data tables

Measured cross section for GAMMA GAMMA --> PBAR P in the angular region ABS(COS(THETA)) < 0.6.

Measured differential cross sections versus COS(THETA) for the W ranges 2.075 to 2.5, 2.5 to 3.0 and 3.0 to 4.0 GeV.

Measured differential cross sections versus COS(THETA) for the W ranges 2.075 to 2.1, 2.1 to 2.2 and 2.2 to 2.3 GeV.

More…

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

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

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.

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…

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

No description provided.

No description provided.