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rivet Analysis
Collins asymmetries in inclusive charged $KK$ and $K\pi$ pairs produced in $e^+e^-$ annihilation

The BaBar collaboration Lees, J.P. ; Poireau, V. ; Tisserand, V. ; et al.

Phys.Rev.D 92 (2015) 111101, 2015.

Inspire Record 1377201 DOI 10.17182/hepdata.73750

We present measurements of Collins asymmetries in the inclusive process $e^+e^- \rightarrow h_1 h_2 X$, $h_1h_2=KK,\, K\pi,\, \pi\pi$, at the center-of-mass energy of 10.6 GeV, using a data sample of 468 fb$^{-1}$ collected by the BaBar experiment at the PEP-II $B$ factory at SLAC National Accelerator Center. Considering hadrons in opposite thrust hemispheres of hadronic events, we observe clear azimuthal asymmetries in the ratio of unlike- to like-sign, and unlike- to all charged $h_1 h_2$ pairs, which increase with hadron energies. The $K\pi$ asymmetries are similar to those measured for the $\pi\pi$ pairs, whereas those measured for high-energy $KK$ pairs are, in general, larger.

6 data tables

Table 1

Light quark ($uds$) Collins asymmetries obtained by fitting the U/L and U/C double ratios as a function of ($z_1$,$z_2$) for kaon pairs. In the first column, the $z$ bins and their respective mean values for the kaon in one hemisphere are reported; in the following column, the same variables for the second kaon are shown; in the third column the mean value of $\sin^2\theta_{th}/(1+\cos^2\theta_{th})$ is summarized, calculated in the RF12 frame; in the last two columns the asymmetry results are summarized. The mean values of the quantities reported in the table are calculated by summing the corresponding values for each $KK$ pair and dividing by the number of $KK$ pairs that fall into each ($z_1$,$z_2$) interval. Note that the $A^{UL}$ and $A^{UC}$ results are strongly correlated since they are obtained by using the same data set.

Table 2

Light quark ($uds$) Collins asymmetries obtained by fitting the U/L and U/C double ratios as a function of ($z_1$,$z_2$) for kaon pairs. In the first column, the $z$ bins and their respective mean values for the kaon in one hemisphere are reported; in the following column, the same variables for the second kaon are shown; in the third column the mean value of $\sin^2\theta_{2}/(1+\cos^2\theta_{2})$ is summarized, calculated in the RF0 frame; in the last two columns the asymmetry results are summarized. The mean values of the quantities reported in the table are calculated by summing the corresponding values for each $KK$ pair and dividing by the number of $KK$ pairs that fall into each ($z_1$,$z_2$) interval. Note that the $A^{UL}$ and $A^{UC}$ results are strongly correlated since they are obtained by using the same data set.

Table 3

Light quark ($uds$) Collins asymmetries obtained by fitting the U/L and U/C double ratios as a function of ($z_1$,$z_2$) for $K\pi$ hadron pairs. In the first column, the $z$ bins and their respective mean values for the hadron ($K$ or $\pi$) in one hemisphere are reported; in the following column, the same variables for the second hadron ($K$ or $\pi$) are shown; in the third column the mean value of $\sin^2\theta_{th}/(1+\cos^2\theta_{th})$ is summarized, calculated in the RF12 frame; in the last two columns the asymmetry results are summarized. The mean values of the quantities reported in the table are calculated by summing the corresponding values for each $K\pi$ pair and dividing by the number of $K\pi$ pairs that fall into each ($z_1$,$z_2$) interval. Note that the $A^{UL}$ and $A^{UC}$ results are strongly correlated since they are obtained by using the same data set.

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rivet Analysis
Observation of an isoscalar vector meson at approximately = 1650-MeV/c**2 in the e+ e- ---> K anti-K pi reaction

Bisello, D. ; Busetto, G. ; Castro, A. ; et al.

Z.Phys.C 52 (1991) 227-230, 1991.

Inspire Record 318558 DOI 10.17182/hepdata.14928

The$e^ +e^ -\to K_s^0 K^ \pm\pi ^ \mp$ andK+K−π0 cross sections have been measured in the energy interval$1350 \leqq \sqrt s\leqq 2400$ with the DM2 detector at DCI. The$K_s^0 K^ \pm\pi ^ \mp$ cross section shows the contribution of an isoscalar vector meson at ≈1650 MeV/c2 in agreement with a previous experiment. The low statisticsK+K−π0 measurement is consistent with the above result.

2 data tables

Table 1

The K0S K+- PI-+ cross section.

Table 2

The K+ K- PI0 cross section.

rivet Analysis
Baryon pair production in e+ e- annihilation at S**(1/2) = 2.4-GeV

The DM2 collaboration Bisello, D. ; Busetto, G. ; Castro, A. ; et al.

Z.Phys.C 48 (1990) 23-28, 1990.

Inspire Record 297706 DOI 10.17182/hepdata.15128

Search for baryon pairs production ine+e− annihilation at$\sqrt s= 2386 MeV$ is reported. The data relate to a luminosity of 161 nb−1 collected by the DM2 experiment at DCI, the Orsay colliding ring. First measurements of directe+e− annihilation into$\Lambda \bar \Lambda $ and ofe+e−→$p\bar p$ at this energy are presented. First observation of a goode+e−→$n\bar n$ candidate is reported and upper limits are given fore+e−→$n\bar n, \Lambda \bar \sum ^0+ c.c.$ and$\Sigma ^0 \bar \Sigma ^0 $.

5 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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rivet Analysis
Study of the Reaction $e^+ e^- \to K^+ K^-$ in the Energy Range 1350 $\le \sqrt{s} \le$ 2400-{MeV}

The DM2 collaboration Bisello, D. ; Busetto, G. ; Castro, A. ; et al.

Z.Phys.C 39 (1988) 13, 1988.

Inspire Record 262690 DOI 10.17182/hepdata.15622

Thee+e−→K+K− cross section has been measured from about 750 events in the energy interval$1350 \leqq \sqrt s\leqq 2400 MeV$ with the DM2 detector at DCI. TheK± form factor |FF±| cannot be explained by the ρ, ω, ϕ and ρ′(1600). An additional resonant amplitude at 1650 MeV has to be added as suggested by a previous experiment.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

ANGULAR AND ENERGY DEPENDENCE OF THE CROSS-SECTION AND ANALYZING POWER OF THE REACTION P P ----> D PI+ BETWEEN 725-MEV AND 1000-MEV

Mayer, B. ; Bertini, R. ; Cameron, J.M. ; et al.

Nucl.Phys.A 437 (1985) 630-642, 1985.

Inspire Record 217258 DOI 10.17182/hepdata.37040

The differential cross section and analyzing power of the reaction pp → d π + were measured for nine incident proton energies between 725 and 1000 MeV. A magnetic spectrometer was used to detect either deuterons or pions. Cross-section and analyzing-power angular distributions were respectively fitted with Legendre polynomial and associated Legendre function expansions, the coefficients of which were found to vary smoothly with energy in the vicinity of the alleged 3 F 3 dibaryon resonance.

12 data tables

Table 1

Data present here in form of Legendre polynomial fit.

Table 2

Legendre Polynomial fit to cross section.

Table 3

Legendre polynomial fit to analysing power.