Angular Distribution of Charge Exchange and Inelastic Neutrons in $\pi^- - p$ Interactions at 313 and 371 MeV

Lind, Don L. ; Barish, Barry C. ; Ku, Richard J. ; et al.
Phys.Rev. 138 (1965) B1509-B1517, 1965.
Inspire Record 1186787 DOI 10.17182/hepdata.467

Neutron angular distributions from the charge-exchange (π0n) and inelastic modes (π0π0n,π+π−n) of the π−−p interaction have been investigated at 313 and 371 MeV incident-pion kinetic energy. The data were obtained with an electronic counter system. Elastic and inelastic neutrons were separated in the all-neutral final states by time of flight. At both energies the charge-exchange differential cross section at the forward neutron angles differs from that determined by Caris et al. from measurements of the π0-decay gamma distributions, but generally agrees with the phase-shift-analysis calculations of Roper. The distribution of inelastic neutrons from both modes shows a strong preference for low center-of-mass neutron energies. The distribution of these neutrons does not correspond to that expected from the I=0, π−π interaction (ABC effect) suggested to account for the anomaly in p−d collisions observed by Abashian et al. Finally, all available charge-exchange differential-cross-section data from this and other experiments were combined by at least-squares fit to a Legendre expansion of the form dσdΩ*(cosθπ0*)=Σl=0NalPl(cosθπ0*) with the following results (in mb/sr):

1 data table match query

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Production of $\pi^0 \pi^0$ and $\pi^0 \eta$ in Photon - Photon Collisions

Edwards, C. ; Partridge, Richard ; Peck, C. ; et al.
Phys.Lett.B 110 (1982) 82-86, 1982.
Inspire Record 168793 DOI 10.17182/hepdata.30959

We investigate the four-photon final state produced in γγ colissions. In the π 0 π 0 channel we observe f(1270) production with predominantly helicity 2 and measure a partial width Γ γγ 2.9 +0.6 −0.4 ± keV (independent of assumptions on the helicity). We observe A 2 (1310) production in the π 0 η channel and find a partial width Γ γγ = 0.77 ± 0.18 ± 0.27 KeV (assuming helicity 2). We give an upper limit for f ≈ ηη .

1 data table match query

Data read from graph.


Limit on the B ---> u Coupling from Semileptonic B Decay

The CLEO collaboration Chen, A. ; Goldberg, M. ; Horwitz, N. ; et al.
Phys.Rev.Lett. 52 (1984) 1084, 1984.
Inspire Record 199380 DOI 10.17182/hepdata.20474

We have used the momentum spectrum of leptons produced in semileptonic B-meson decays to set a 90%-confidence-level upper limit on Γ(b→ulν)Γ(b→clν) of 4%. We also measure the semileptonic branching fractions of the B meson to be (12.0±0.7±0.5)% for electrons and (10.8±0.6±1.0)% for muons.

2 data tables match query

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Cross sections for the reactions $e^+ e^-\to K_S^0 K_L^0$, $K_S^0 K_L^0 \pi^+\pi^-$, $K_S^0 K_S^0 \pi^+\pi^-$, and $K_S^0 K_S^0 K^+K^-$ from events with initial-state radiation

The BaBar collaboration Lees, J.P. ; Poireau, V. ; Tisserand, V. ; et al.
Phys.Rev.D 89 (2014) 092002, 2014.
Inspire Record 1287920 DOI 10.17182/hepdata.64506

We study the processes $e^+ e^-\to K_S^0 K_L^0 \gamma$, $K_S^0 K_L^0 \pi^+\pi^-\gamma$, $K_S^0 K_S^0 \pi^+\pi^-\gamma$, and $K_S^0 K_S^0 K^+K^-\gamma$, where the photon is radiated from the initial state, providing cross section measurements for the hadronic states over a continuum of center-of-mass energies. The results are based on 469 fb$^{-1}$ of data collected with the BaBar detector at SLAC. We observe the $\phi(1020)$ resonance in the $K_S^0 K_L^0$ final state and measure the product of its electronic width and branching fraction with about 3% uncertainty. We present a measurement of the $e^+ e^-\to K_S^0 K_L^0 $ cross section in the energy range from 1.06 to 2.2 GeV and observe the production of a resonance at 1.67 GeV. We present the first measurements of the $e^+ e^-\to K_S^0 K_L^0 \pi^+\pi^-$, $K_S^0 K_S^0 \pi^+\pi^-$, and $K_S^0 K_S^0 K^+K^-$ cross sections, and study the intermediate resonance structures. We obtain the first observations of \jpsi decay to the $K_S^0 K_L^0 \pi^+\pi^-$, $K_S^0 K_S^0 \pi^+\pi^-$, and $K_S^0 K_S^0 K^+K^-$ final states.

8 data tables match query

Cross section measurement for PHI(1020).

Mass measurement for PHI(1020).

Measurement of the PHI(1020) width.

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Analysis of the pi+ pi- pi+ pi- and pi+ pi0 pi- pi0 final states in quasi-real two-photon collisions at LEP

The L3 collaboration Achard, P. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
Phys.Lett.B 638 (2006) 128-139, 2006.
Inspire Record 705125 DOI 10.17182/hepdata.48674

The reactions gamma gamma -> pi^+pi^-pi^+pi^- and gamma gamma -> pi^+pi^0pi^-pi^0 are studied with the L3 detector at LEP in a data sample collected at centre-of-mass energies from 161GeV to 209GeV with a total integrated luminosity of 698/pb. A spin-parity-helicity analysis of the rho^0 rho^0 and rho^+ rho^- systems for two-photon centre-of-mass energies between 1GeV and 3GeV shows the dominance of the spin-parity state 2+ with helicity 2. The contribution of 0+ and 0- spin-parity states is also observed, whereas contributions of 2- states and of a state with spin-parity 2+ and zero helicity are found to be negligible.

4 data tables match query

Cross section for 4PI and (RHO0 RHO0) production.

Cross section for 4PI and (RHO+ RHO-) production.

Spin parity analysis fits for RHO0 RHO0.

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Coincidence electroproduction of single neutral pions in the resonance region at q 2 = 0.5 (GeV/ c ) 2

Latham, A. ; Allison, J. ; Booth, I. ; et al.
Nucl.Phys.B 156 (1979) 58-92, 1979.
Inspire Record 1392686 DOI 10.17182/hepdata.836

Data are presented for the reaction ep → ep π 0 at a nominal four-momentum transfer squared of 0.5 (GeV/ c ) 2 . The data were obtained using an extracted electron beam from NINA and two magnetic spectrometers for coincidence detection of the electron and proton. Details are given of the experimental method and the results are given for isobar masses in the range 1.19 – 1.73 GeV/ c 2 .

4 data tables match query

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Backward cross sections.

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A Kinematically complete measurement of the proton structure function F(2) in the resonance region and evaluation of its moments

The CLAS collaboration Osipenko, M. ; Ricco, G. ; Taiuti, M. ; et al.
Phys.Rev.D 67 (2003) 092001, 2003.
Inspire Record 612145 DOI 10.17182/hepdata.12253

We measured the inclusive electron-proton cross section in the nucleon resonance region (W < 2.5 GeV) at momentum transfers Q**2 below 4.5 (GeV/c)**2 with the CLAS detector. The large acceptance of CLAS allowed for the first time the measurement of the cross section in a large, contiguous two-dimensional range of Q**2 and x, making it possible to perform an integration of the data at fixed Q**2 over the whole significant x-interval. From these data we extracted the structure function F2 and, by including other world data, we studied the Q**2 evolution of its moments, Mn(Q**2), in order to estimate higher twist contributions. The small statistical and systematic uncertainties of the CLAS data allow a precise extraction of the higher twists and demand significant improvements in theoretical predictions for a meaningful comparison with new experimental results.

46 data tables match query

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Measurement of exclusive rho+ rho- production in high-Q**2 two-photon collisions at LEP

The L3 collaboration Achard, P. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
Phys.Lett.B 597 (2004) 26-38, 2004.
Inspire Record 654177 DOI 10.17182/hepdata.48589

Exclusive rho^+ rho^- production in two-photon collisions involving a single highly-virtual photon is studied with data collected at LEP at centre-of-mass energies 89 GeV &lt; \sqrt{s} &lt; 209 GeV with a total integrated luminosity of 854.7 pb^-1. The cross section of the process gamma gamma^* -> rho^+ rho^- is determined as a function of the photon virtuality, Q^2, and the two-photon centre-of-mass energy, W_gg, in the kinematic region: 1.2 GeV^2 &lt; Q^2 &lt; 30 GeV^2 and 1.1 GeV &lt; W_gg &lt; 3 GeV. The \rho^+\rho^- production cross section is found to be of the same magnitude as the cross section of the process gamma gamma^* -> rho^0 rho^0, measured in the same kinematic region by L3, and to have similar W_gg and Q^2 dependences.

9 data tables match query

Cross sections for the reaction E+ E- --> E+ E- RHO+ RHO-. The differentialcross sections are corrected to the centre of each bin.

Cross sections for the two photon production of RHO+ RHO-.

Differential cross section for the process E+ E- --> E+ E- (RHO+ PI- PI0 + RHO+ RHO- PI0 PI0) corrected to bin centre.

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Differential Cross-Sections for the pi0 Photoproduction at Theta (CM) = 90-Degrees and K (Lab) = 380-MeV-820-MeV

Jung, M. ; Kattein, J. ; Leu, P. ; et al.
1976.
Inspire Record 111677 DOI 10.17182/hepdata.50235
1 data table match query

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Radiative pi0 photoproduction on protons in the Delta+(1232) region

Schumann, S. ; Boillat, B. ; Downie, E.J. ; et al.
Eur.Phys.J.A 43 (2010) 269-282, 2010.
Inspire Record 843314 DOI 10.17182/hepdata.54377

The reaction gamma p -> p pi0 gamma' has been measured with the Crystal Ball / TAPS detectors using the energy-tagged photon beam at the electron accelerator facility MAMI-B. Energy and angular differential cross sections for the emitted photon gamma' and angular differential cross sections for the pi0 have been determined with high statistics in the energy range of the Delta+(1232) resonance. Cross sections and the ratio of the cross section to the non-radiative process gamma p -> p pi0 are compared to theoretical reaction models, having the anomalous magnetic moment kappa_Delta+ as free parameter. As the shape of the experimental distributions is not reproduced in detail by the model calculations, currently no extraction of kappa_Delta+ is feasible.

2 data tables match query

Total cross section for the background reaction GAMMA P --> P PI0.

Total cross section for the background reaction GAMMA P --> P PI0 PI0.