Measurement of the Sigma- charge radius by Sigma- electron elastic scattering.

The SELEX collaboration Gough Eschrich, Ivo M. ; Kruger, H. ; Simon, J. ; et al.
Phys.Lett.B 522 (2001) 233-239, 2001.
Inspire Record 558329 DOI 10.17182/hepdata.42898

The Sigma^- mean squared charge radius has been measured in the space-like Q^2 range 0.035-0.105 GeV^2/c^2 by elastic scattering of a Sigma^- beam off atomic electrons. The measurement was performed with the SELEX (E781) spectrometer using the Fermilab hyperon beam at a mean energy of 610 GeV/c. We obtain <r^2> = (0.61 +/- 0.12 (stat.) +/- 0.09 (syst.)) fm^2. The proton and pi^- charge radii were measured as well and are consistent with results of other experiments. Our result agrees with the recently measured strong interaction radius of the Sigma^-.

1 data table match query

Total systematic errors are given.


High statistics measurement of the cross sections of gamma gamma --> pi+ pi- production.

The Belle collaboration Mori, T. ; Uehara, S. ; Watanabe, Y. ; et al.
J.Phys.Soc.Jap. 76 (2007) 074102, 2007.
Inspire Record 749358 DOI 10.17182/hepdata.51842

We report on a high statistics measurement of the total and differential cross sections of the process gamma gamma -> pi^+ pi^- in the pi^+ pi^- invariant mass range 0.8 GeV/c^2 < W < 1.5 GeV/c^2 with 85.9 fb^{-1} of data collected at sqrt{s}=10.58 GeV and 10.52 GeV with the Belle detector. A clear signal of the f_0(980) resonance is observed in addition to the f_2(1270) resonance. An improved 90% confidence level upper limit Br.(eta'(958) -> pi^+ pi^-) < 2.9 x 10^{-3} is obtained for P- and CP-violating decay of the eta'(958) meson using the most conservative assumption about the interference with the background.

1 data table match query

Total cross section.


Measurement of the Recoil Proton Polarization in Elastic $\pi^-p$ Scattering at $T_\pi=410$ and 492 MeV

Bareyre, P. ; Bricman, C. ; Longo, M.J. ; et al.
Phys.Rev.Lett. 14 (1965) 878-880, 1965.
Inspire Record 945162 DOI 10.17182/hepdata.21824

None

1 data table match query

No description provided.


Measurement of the Recoil Proton Polarization in Elastic pi+p Scattering at Tpi=410and492 MeV

Bareyre, P. ; Bricman, C. ; Longo, M.J. ; et al.
Phys.Rev.Lett. 14 (1965) 198-201, 1965.
Inspire Record 944925 DOI 10.17182/hepdata.21847

None

1 data table match query

No description provided.


Proton Compton scattering at 0.55-to-4.5-gev energy and 0.12-to-1.0-(gev/c)-squared momentum transfer

Deutsch, M. ; Cleetus, K.J. ; Golub, L. ; et al.
Phys.Rev.D 8 (1973) 3828-3847, 1973.
Inspire Record 93270 DOI 10.17182/hepdata.22057

Results are presented on the elastic scattering of photons by protons. The incident photon energy ranged from 0.55 GeV to 4.5 GeV, and the four-momentum transfer t ranged from 0.12 to 1.0 (GeV/c)2. The data at large angles, 60°<θ*<115°, are characterized by a pronounced excitation of the D13(1518) resonance, a shoulder in the 1688-MeV mass region, and a precipitous drop thereafter in the cross section as a function of incident energy. The low-t data are characterized by a diffraction slope of 5 (GeV/c)−2. The data are inconsistent with the predictions of the vector-dominance model if the latter is restricted to ρ0, ω, and φ vector mesons.

1 data table match query

No description provided.


The Pion Electromagnetic Form-factor in the Timelike Energy Range 1.35-{GeV} $\le \sqrt{s} \le$ 2.4-{GeV}

The DM2 collaboration Bisello, D. ; Busetto, G. ; Castro, A. ; et al.
Phys.Lett.B 220 (1989) 321-327, 1989.
Inspire Record 267118 DOI 10.17182/hepdata.29829

The e + e − → π + π − cross section has been measured from about 280 events (an order of magnitude more than the previous world statistics) in the energy interval 1.35 ⩽ s ⩽ 2.4 GeV with the DM2 detector at DCI. The pion squared form factor | F π | 2 shows a deep minimum around 1.6 GeV/ c 2 and is better fit under the hypothesis of two ϱ-like resonance ⋍0.25 GeV/ c 2 wide with 1.42 and 1.77 GeV/ c 2 masses.

1 data table match query

Statistical errors only.


Measurement of $\pi^- p \to \pi^- p \pi^0$ Reaction Near Threshold and Breaking of Chiral Symmetry

The OMICRON collaboration Kernel, G. ; Korbar, D. ; Krizan, P. ; et al.
Phys.Lett.B 225 (1989) 198-202, 1989.
Inspire Record 278272 DOI 10.17182/hepdata.29804

A full-kinematics measurement of the π − p→ π − p π 0 reaction in the incident π − momentum region from 295 to 450 MeV/ c is presented. The measurement was performed with the OMICRON spectrometer at the CERN synchrocyclotron.

1 data table match query

Integrated cross section.


Rho Production by Virtual Photons

Joos, P. ; Ladage, A. ; Meyer, H. ; et al.
Nucl.Phys.B 113 (1976) 53-92, 1976.
Inspire Record 108749 DOI 10.17182/hepdata.35708

The reaction γ V p → p π + π − was studied in the W , Q 2 region 1.3–2.8 GeV, 0.3–1.4 GeV 2 using the streamer chamber at DESY. A detailed analysis of rho production via γ V p→ ϱ 0 p is presented. Near threshold rho production has peripheral and non-peripheral contributions of comparable magnitude. At higher energies ( W > 2 GeV) the peripheral component is dominant. The Q 2 dependence of σ ( γ V p→ ϱ 0 p) follows that of the rho propagator as predicted by VDM. The slope of d σ /d t at 〈 Q 2 〉 = 0.4 and 0.8 GeV 2 is within errors equal to its value at Q 2 = 0. The overall shape of the ϱ 0 is t dependent as in photoproduction, but is independent of Q 2 . The decay angular distribution shows that longitudinal rhos dominate in the threshold region. At higher energies transverse rhos are dominant. Rho production by transverse photons proceeds almost exclusively by natural parity exchange, σ T N ⩾ (0.83 ± 0.06) σ T for 2.2 < W < 2.8 GeV. The s -channel helicity-flip amplitudes are small compared to non-flip amplitudes. The ratio R = σ L / σ T was determined assuming s -channel helicity conservation. We find R = ξ 2 Q 2 / M ϱ 2 with ξ 2 ≈ 0.4 for 〈 W 〉 = 2.45 GeV. Interference between rho production amplitudes from longitudinal and transverse photons is observed. With increasing energy the phase between the two amplitudes decreases. The observed features of rho electroproduction are consistent with a dominantly diffractive production mechanism for W > 2 GeV.

1 data table match query

DIPION CHANNEL CROSS SECTION.


Compton scattering by the proton through Theta(CMS) = 75-degrees and 90-degrees in the Delta resonance region

Hünger, A ; Peise, J ; Robbiano, A ; et al.
Nucl.Phys.A 620 (1997) 385-416, 1997.
Inspire Record 458618 DOI 10.17182/hepdata.36349

Differential cross sections for Compton scattering by the proton have been measured in the energy interval between 200 and 500 MeV at scattering angles of θ cms = 75° and θ cms = 90° using the CATS, the CATS/TRAJAN, and the COPP setups with the Glasgow Tagger at MAMI (Mainz). The data are compared with predictions from dispersion theory using photo-meson amplitudes from the recent VPI solution SM95. The experiment and the theoretical procedure are described in detail. It is found that the experiment and predictions are in agreement as far as the energy dependence of the differential cross sections in the Δ-range is concerned. However, there is evidence that a scaling down of the resonance part of the M 1+ 3 2 photo-meson amplitude by (2.8 ± 0.9)% is required in comparison with the VPI analysis. The deduced value of the M 1+ 3 2 - photoproduction amplitude at the resonance energy of 320 MeV is: |M 1+ 3 2 | = (39.6 ± 0.4) × 10 −3 m π + −1 .

1 data table match query

No description provided.


INELASTIC ELECTRON PHOTON SCATTERING AT MODERATE FOUR MOMENTUM TRANSFERS

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Phys.Lett.B 99 (1981) 287-291, 1981.
Inspire Record 155594 DOI 10.17182/hepdata.27125

We present new high statistics data on hadron production in photon-photon reactions. The data are analyzed in terms of an electron-photon scattering formalism. The dependence of the total cross section of Q 2 , the four-momentum transfer squared of the scattered electron, and on the mass W of the hadronic system is investigated. The data are compared to predictions from Vector-Meson Dominance and the quark model.

1 data table match query

DEPENDENCE ON VISIBLE HADRONIC INVARIANT MASS.


Forward Electroproduction of Single Charged Pions in the Resonance Region Using a Deuterium Target

Morris, J.V. ; Darvill, D.C. ; Davenport, M. ; et al.
Phys.Lett.B 73 (1978) 495-499, 1978.
Inspire Record 122614 DOI 10.17182/hepdata.27480

The rates for forward electroproduction of single charged pions from deutrium have been measured in the resonance region, at a virtual photon mass squared ≈−0.5( GeV/ c 2 ) 2 . Results are presented in the form of a π − to π + cross-section ratio.

1 data table match query

No description provided.


FORWARD ELECTROPRODUCTION OF CHARGED PIONS FROM DEUTERONS AT Q**2 = 1.0-GeV/c**2

Morris, J.V. ; Darvill, D.C. ; Davenport, M. ; et al.
Phys.Lett.B 86 (1979) 211-214, 1979.
Inspire Record 140702 DOI 10.17182/hepdata.27310

The ratio of π - to π + electroproduction cross sections from deuterium has been measured in the resonance region, at a four-momentum transfer squared close to −1.0 (GeV/ c ) 2 . Results in the forward direction are presented and a comparison is made with predictions based on SU(6) W and the Melosh transformation.

1 data table match query

No description provided.


Hadron Production From Photon - Photon Interactions in the Center-of-mass Energy Range From 1-{GeV} to 5-{GeV}

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Phys.Lett.B 89 (1979) 120-124, 1979.
Inspire Record 142875 DOI 10.17182/hepdata.27291

We present the first data on photon-photon annihilation into hadrons for CM energies > 1 GeV obtained with the detector PLUTO at the e + e − storage ring PETRA. Cross sections are extracted using an inelastic eγ scattering formalism. The results are compared to expectations from Regge-like models.

1 data table match query

DEPENDENCE OF CROSS SECTION FOR ELECTRON-PHOTON SCATTERING (ANALOGOUS TO HAND'S FORMULA) ON VISIBLE HADRONIC ENERGY, CALCULATED BY TAKING PION MASSES FOR ALL CHARGED PARTICLES.


Inclusive K0(s) Production in e+ e- Annihilation at Energies of 3.6-GeV to 5.0-GeV

The PLUTO collaboration Burmester, J. ; Criegee, L. ; Dehne, H.C. ; et al.
Phys.Lett.B 67 (1977) 367-370, 1977.
Inspire Record 118873 DOI 10.17182/hepdata.27568

We have measured the production cross section for K s 0 in e + e − annihilation from 3.6 to 5.0 GeV center of mass energy. A substantial increase of the K s 0 yield is observed around 4 GeV in qualitative agreement with the charm hypothesis.

1 data table match query

No description provided.


Inclusive hadron photoproduction from longitudinally polarized protons and deuterons.

The E155 collaboration Anthony, P.L. ; Arnold, R.G. ; Averett, T. ; et al.
Phys.Lett.B 458 (1999) 536-544, 1999.
Inspire Record 495554 DOI 10.17182/hepdata.28074

We report measurements of the asymmetry A_parallel for inclusive hadron production on longitudinally polarized proton and deuteron targets by circularly polarized photons. The photons were produced via internal and external bremsstrahlung from an electron beam of 48.35 GeV. Asymmetries for both positive and negative signed hadrons, and a subset of identified pions, were measured in the momentum range 10<P<30 GeV at 2.75 and 5.5 degrees. Small non-zero asymmetries are observed for the proton, while the deuteron results are consistent with zero. Recent calculations do not describe the data well.

2 data tables match query

The asymmetry for polarized photoproduction of inclusive hadrons from a polarized proton target. The errors are statistical only.

The asymmetry for polarized photoproduction of inclusive identified pions from a polarized proton target. The errors are statistical only.


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 .

6 data tables match query

No description provided.

No description provided.

No description provided.

More…

Tensor Meson Excitation in the Reaction $\gamma \gamma \to K^0_S K^0_S$

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Lackas, W. ; et al.
Z.Phys.C 37 (1988) 329, 1988.
Inspire Record 250982 DOI 10.17182/hepdata.15690

In the analysis of the reactione+e−→e+e−KS0Ks0 clear evidence for exclusive γγ→f2′ resonance production is observed. The productΓγγ ·B(f2′→K\(\bar K\)) is measured to be 0.10−0.03−0.02+0.04+0.03 keV independent of ana priori assumption on the helicity structure. Our data are consistent with a pure helicity 2 contribution and we derive an upper limit for the ratioΓγγ(0)/Γγγ. The absence of events in the mass region around 1.3 GeV clearly proves destructivef2−a2 interference and allows to measure the relative phases betweenf2,a2 andf2′. Upper limits on the production of the glueball candidate statesf2(1720) andX(2230) as well as theKS0KS0-continuum are given.

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

No description provided.

No description provided.


Axial and pseudoscalar nucleon form-factors from low-energy pion electroproduction

Choi, Seonho ; Estenne, V. ; Bardin, G. ; et al.
Phys.Rev.Lett. 71 (1993) 3927-3930, 1993.
Inspire Record 360772 DOI 10.17182/hepdata.19697

The cross section for exclusive π+ electroproduction on the proton has been measured near threshold for the first time at two different values of the virtual photon polarization (ɛ∼0.2 and ɛ∼0.7). Using the low energy theorem for this reaction we deduce the axial and pseudoscalar weak form factors GA and GP at ‖t‖=0.073, 0.139, and 0.179 (GeV/c)2. The slope of GA agrees with the value obtained in neutrino experiments. GP satisfies the pion pole dominance hypothesis, which is thus verified for the first time in this range of transfer.

3 data tables match query

No description provided.

No description provided.

No description provided.


In-medium modifications of the pi pi interaction in photon-induced reactions.

Messchendorp, J.G ; Janssen, S. ; Kotulla, M. ; et al.
Phys.Rev.Lett. 89 (2002) 222302, 2002.
Inspire Record 586889 DOI 10.17182/hepdata.19419

Differential cross sections of the reactions $(\gamma,\pi^\circ\pi^\circ)$ and $(\gamma,\pi^\circ\pi^++\pi^\circ\pi^-)$ have been measured for several nuclei ($^1$H,$^{12}$C, and $^{\rm nat}$Pb) at an incident-photon energy of $E_{\gamma}$=400-460 MeV at the tagged-photon facility at MAMI-B using the TAPS spectrometer. A significant nuclear-mass dependence of the $\pi\pi$ invariant-mass distribution is found in the $\pi^\circ\pi^\circ$ channel. This dependence is not observed in the $\pi^\circ\pi^{+/-}$ channel and is consistent with an in-medium modification of the $\pi\pi$ interaction in the $I$=$J$=0 channel. The data are compared to $\pi$-induced measurements and to calculations within a chiral-unitary approach.

2 data tables match query

Differential cross section for PI0PI0 production with a proton target. Errors are statistical only. Note that the data given in this table are sightly different (newer) than the data points presented in the paper.

Differential cross section for PI0PI+ production with a proton target. Errors are statistical only. Note that the data given in this table are sightly different (newer) than the data points presented in the paper.


Angular distributions for single neutral pion photoproduction from neutrons at 450-800 mev

Bacci, C. ; Baldini-Celio, R. ; Esposito, B. ; et al.
Phys.Lett.B 39 (1972) 559-562, 1972.
Inspire Record 75766 DOI 10.17182/hepdata.28319

Differential cross sections for single photoproduction of neutral pion on neutron have been measured at different c.m. angles for photon energies, between 450–800 MeV.

1 data table match query

No description provided.


Total cross-section measurement for the three double pion production channels on the proton

Braghieri, A ; Murphy, L.Y ; Ahrens, J ; et al.
Phys.Lett.B 363 (1995) 46-50, 1995.
Inspire Record 382744 DOI 10.17182/hepdata.28464

The total cross sections for the three γp → Nππ reactions have been measured for photon energies from 400 to 800 MeV. The γ p → p π 0 π 0 and γ p → n π + π 0 cross sections have never been measured before while the γ p → p π + π − results are much improved compared to earlier data. These measurements were performed with the large acceptance hadronic detector DAPHNE, at the tagged photon beam facility of the MAMI microtron in Mainz.

3 data tables match query

No description provided.

No description provided.

No description provided.


Electromagnetic form-factors of the proton at squared four momentum transfers between 10-fm**-2 and 50 fm**-2

Berger, C ; Burkert, V. ; Knop, G. ; et al.
Phys.Lett.B 35 (1971) 87-89, 1971.
Inspire Record 69362 DOI 10.17182/hepdata.28478

Electron-proton elastic scattering cross sections have been measured to determine the proton electromagnetic form factors at squared four-momentum transfers q 2 between 10 and 50 fm −2 . At these values of q 2 we measured angular distributions between 25° and 110° and in addition at 25° and 35° cross sections for q 2 from 2 to 20 fm −2 using the external electron beam of the Bonn 2.5 GeV electron synchrotron. Our results confirm deviations from the scaling law.

1 data table match query

Axis error includes +- 2/2 contribution (NORMALIZATION ERROR).


MEASUREMENT OF THE ASYMMETRY PARAMETER A IN PI- P ELASTIC AND CHARGE EXCHANGE SCATTERING AT PION ENERGIES T (PI) = 98-MEV, 238-MEV, 292-MEV, AND 310-MEV

Alder, J.c. ; Joseph, C. ; Perroud, J.p. ; et al.
Phys.Rev.D 27 (1983) 1040-1055, 1983.
Inspire Record 192365 DOI 10.17182/hepdata.23839

The asymmetry parameter A in π−p elastic scattering at incident pion laboratory kinetic energies Tπ of 98, 238, and 2922 MeV and in π−p charge-exchange scattering π−p→π0n at Tπ=238, 292, and 310 MeV have been measured over a wide range of scattering angles (typically from about 60° to 130° c.m.) with a polarized proton target. The data have been used in an energy-independent phase-shift analysis to improve the precision of the pion-nucleon phase shifts, to set new limits on violation of isospin conservation in the pion-nucleon S wave, and to confirm significant charge dependence in the P32 wave.

3 data tables match query

Axis error includes +- 0.0/0.0 contribution (?////BACKGROUND SUBTRACTION SMALL).

Axis error includes +- 5/5 contribution (BACKGROUND SUBTRACTION).

Axis error includes +- 5/5 contribution (BACKGROUND SUBTRACTION).


Measurement of the Parameters of the $\psi^{\prime\prime}$(3770) Resonance

Abrams, G.S. ; Alam, M.S. ; Blocker, C.A. ; et al.
Phys.Rev.D 21 (1980) 2716, 1980.
Inspire Record 142644 DOI 10.17182/hepdata.24185

We present a measurement of the cross section for hadron production by e+e− annihilation in the vicinity of the previously observed resonance near 3.77 GeV. The data are used to determine the parameters of the ψ(3770) resonance. The values found are: mass, 3764±5 MeV/c2, total width, 23.5±5 MeV, and partial width to electron pairs, 276±50 eV.

1 data table match query

PEAK CROSS SECTION FOR D MESON PAIR PRODUCTION AT PSI(3770) RESONANCE. J/PSI, PSI(3684) AND CONTINUUM BACKGROUND (R=2.5) SUBTRACTED.