HEPData Search

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Angular analysis of $B^0 \to K^\ast(892)^0 \ell^+ \ell^-$

The Belle collaboration Abdesselam, A. ; Adachi, I. ; Adamczyk, K. ; et al.

BELLE-CONF-1603, 2016.

Inspire Record 1446979 DOI 10.17182/hepdata.72558

We present a measurement of angular observables, $P_4'$, $P_5'$, $P_6'$, $P_8'$, in the decay $B^0 \to K^\ast(892)^0 \ell^+ \ell^-$, where $\ell^+\ell^-$ is either $e^+e^-$ or $\mu^+\mu^-$. The analysis is performed on a data sample corresponding to an integrated luminosity of $711~\mathrm{fb}^{-1}$ containing $772\times 10^{6}$ $B\bar B$ pairs, collected at the $\Upsilon(4S)$ resonance with the Belle detector at the asymmetric-energy $e^+e^-$ collider KEKB. Four angular observables, $P_{4,5,6,8}'$ are extracted in five bins of the invariant mass squared of the lepton system, $q^2$. We compare our results for $P_{4,5,6,8}'$ with Standard Model predictions including the $q^2$ region in which the LHCb collaboration reported the so-called $P_5'$ anomaly.

1 data table

Table 1

Results of the angular analysis of $B^0 \to K^\ast(892)^0 \ell^+ \ell^-$ (where $\ell = e,\mu$) in five bins of $q^2$, the di-lepton invariant mass squared.

EXPERIMENTAL STUDY OF THE pi+ p ---> K+ SIGMA+ REACTION AT 12-GeV/c

The Dubna-Serpukhov-Baku-Bratislava-Gomel-Yerevan-Kiev-Kosice- Minsk-Samarkand-Tbilisi collaboration Bitsadze, G.S. ; Budagov, Yu.A. ; Vinogradov, V.B. ; et al.

Nucl.Phys.B 260 (1985) 497-509, 1985.

Inspire Record 207765 DOI 10.17182/hepdata.33721

The results of the study of the π + p→K + ∑ + (1) and π + p→K + ∑ + (1385) (2) reactions at 12 GeV/ c are presented. The differential cross sections d σ /d t in| t min |<| t |<0.8 (GeV/ c ) 2 momentum transfer range are measured. The ∑ + polarisation for | t |<0.5 (GeV/ c ) 2 for reaction (1) is defined. Binary reactions (1) and (2) were selected by analyzing the missing mass spectra for the forward emitted fast K + meson. The total cross sections in the studied momentum transfer range are 20.2±2.4 μ b and 7.3±1.1 μ b for the reactions (1) and (2) respectively. The experimental results are compared with the predictions of the Regge models which take into account rescattering and secondary singularities.

4 data tables

Table 1

SYSTEMATIC ERRORS INCLUDED.

Table 2

No description provided.

Table 3

No description provided.

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Polarization of Sigma+ and anti-Sigma- hyperons produced by 800-GeV/c protons

The E761 collaboration Morelos Pineda, Antonio ; Albuquerque, I.F. ; Bondar, N.F. ; et al.

Phys.Rev.Lett. 71 (1993) 2172-2175, 1993.

Inspire Record 356301 DOI 10.17182/hepdata.19722

We have mesured the polarization of 375-GeV/c Σ+ and Σ¯ − hyperons produced by 800-GeV/c protons incident on a Cu target. We find that the Σ+ polarization rises with increasing pt to a maximum of 16% at pt=1.0 GeV/c and then decreases to 10% at pt=1.8 GeV/c. We compare this Σ+ polarization with data at lower energies. The Σ¯ − polarization has been measured for the first time. It has the same sign as the Σ+ but smaller magnitude in a similar kinematical region.

4 data tables

Table 1

Data from Horizontal targeting.

Table 2

Data from Vertical targeting.

Table 3

Data from Horizontal targeting.

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P(t) and X(F) dependence of the polarization of Sigma+ hyperons produced by 800-GeV/c protons

The E761 collaboration Morelos Pineda, Antonio ; Albuquerque, I.F. ; Bondar, N.F. ; et al.

Phys.Rev.D 52 (1995) 3777-3780, 1995.

Inspire Record 360549 DOI 10.17182/hepdata.42500

We utilize the angle and momentum resolution of our apparatus to study the polarization of 375 GeV/c Σ+ hyperons produced by 800 GeV/c protons incident on a Cu target. By examining in detail two of our high statistics data samples, we find evidence for structure in the pt dependence of Σ+ polarization and are able to extract the xF dependence of the Σ+ polarization and compare it with xF behavior in the Λ0 and Ξ− systems.

9 data tables

Table 1

0.9 mrad horizontal sample.

Table 2

2.9 mrad horizontal sample.

Table 3

3.3 mrad horizontal sample.

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Measurement of the spin rotation parameter A+ in the elastic scattering of positive pions on a longitudinally polarized proton target in the second resonance region

The ITEP-PNPI collaboration Alekseev, I.G. ; Bobchenko, B.M. ; Budkovsky, P.E. ; et al.

Phys.Lett.B 351 (1995) 585-590, 1995.

Inspire Record 403317 DOI 10.17182/hepdata.28540

The ITEP-PNPI collaboration presents the first results of the spin rotation parameter A + measurements in the second resonance region. The experiment was performed at the ITEP accelerator at a positive pion beam momentum 1.43 GeV/c for scattering angles θ cm = 127° and 133°. The setup was based on a polarized proton target and a carbon-plate polarimeter. The obtained data is compared with the predictions of the existing partial-wave analyses.

1 data table

Table 1

No description provided.

Measurements of spin rotation parameter A in pion proton elastic scattering at 1.62-GeV/c.

The ITEP-PNPI collaboration Alekseev, I.G. ; Budkovsky, P.E. ; Kanavets, V.P. ; et al.

Phys.Lett.B 485 (2000) 32-36, 2000.

Inspire Record 526552 DOI 10.17182/hepdata.41744

The ITEP-PNPI collaboration presents the results of the measurements of the spin rotation parameter A in the elastic scattering of positive and negative pions on protons at P_beam = 1.62 GeV/c. The setup included a longitudinally-polarized proton target with superconductive magnet, multiwire spark chambers and a carbon polarimeter with thick filter. Results are compared to the predictions of partial wave analyses. The experiment was performed at the ITEP proton synchrotron, Moscow.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Inclusive $\bar{\Lambda}$ Polarization in $K^+ p$ Interactions at 32-{GeV}/$c$ and 70-{GeV}/$c$

The Soviet-CERN collaboration Azhinenko, I.V. ; Amaglobeli, N.S. ; Baland, J.F. ; et al.

Phys.Lett.B 121 (1983) 183, 1983.

Inspire Record 179546 DOI 10.17182/hepdata.41221

We present results on the inclusive polarization of Λ hyperons produced in K + p interactions at 32 and 70 GeV/ c . A large positive Λ polarization is observed in the kaon fragmentation region. The polarization is energy independent, increases strongly with increasing x , but shows essentially no p T -dependence.

8 data tables

Table 1

Table 2

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