Forward $\pi^-p$ charge exchange scattering between 0.8 and 1.9 GeV

Borgeaud, P. ; Bruneton, C. ; Ducros, Y. ; et al.
Phys.Lett. 10 (1964) 134-137, 1964.
Inspire Record 1400914 DOI 10.17182/hepdata.31224

None

15 data tables

No description provided.

No description provided.

No description provided.

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Impact parameter dependence of high-energy gamma-ray production in argon induced reaction at 85 MeV/nucleon

Njock, M. Kwato ; Maurel, M. ; Monnand, E. ; et al.
Nucl.Phys.A 489 (1988) 368-380, 1988.
Inspire Record 1389759 DOI 10.17182/hepdata.37000

The double-differential cross sections for high-energy γ-rays were measured for collisions of 36Ar on C, Al, Cu, Ag, Tb, and Au at 85 MeV/nucleon. The system 36Ar+ 27Al has been studied in more detail in an exclusive experiment where the charged-particle multiplicity was measured in coincidence with high-energy γ-rays. A clear correlation between the hardness of the γ-spectra and the overlap distance of the two ions is observed. This correlation is interpreted as due to the spatial dependence of the Fermi momentum of the nucleons.

2 data tables

No description provided.

No description provided.


Measurement of the g p -> K^0 Sigma^+ reaction with the Crystal Ball/TAPS detectors at the Mainz Microtron

The A2 collaboration Aguar-Bartolome, P. ; Annand, J.R.M. ; Arends, H.J. ; et al.
Phys.Rev.C 88 (2013) 044601, 2013.
Inspire Record 1237227 DOI 10.17182/hepdata.64391

The g p -> K^0 Sigma^+ reaction has been measured from threshold to Eg=1.45 GeV (W_cm=1.9 GeV) using the Crystal Ball and TAPS multiphoton spectrometers together with the photon tagging facility at the Mainz Microtron MAMI. In the present experiment, this reaction was searched for in the 3pi^0 p final state, by assuming K^0_S -> pi^0 pi^0 and Sigma^+ -> pi^0 p. The experimental results include total and differential cross sections as well as the polarization of the recoil hyperon. The new data significantly improve empirical knowledge about the g p -> K^0 Sigma^+ reaction in the measured energy range. The results are compared to previous measurements and model predictions. It is demonstrated that adding the present g p -> K^0 Sigma^+ results to existing data allowed a better description of this reaction with various models.

4 data tables

The differential cross section for photon energies 1125, 1175 and 1225 MeV.

The differential cross section for photon energies 1275, 1325, 1375 and 1425 MeV.

The recoil polarization of the SIGMA+ for photon energy 1125, 1175 and 1225 MeV.

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Study of the gp-->etap reaction with the Crystal Ball detector at the Mainz Microtron(MAMI-C)

The Crystal Ball at MAMI collaboration McNicoll, E.F. ; Prakhov, S. ; Strakovsky, I.I. ; et al.
Phys.Rev.C 82 (2010) 035208, 2010.
Inspire Record 860725 DOI 10.17182/hepdata.56733

The gp-->etap reaction has been measured with the Crystal Ball and TAPS multiphoton spectrometers in the energy range from the production threshold of 707 MeV to 1.4 GeV (1.49 =< W >= 1.87 GeV). Bremsstrahlung photons produced by the 1.5-GeV electron beam of the Mainz Microtron MAMI-C and momentum analyzed by the Glasgow Tagging Spectrometer were used for the eta-meson production. Our accumulation of 3.8 x 10^6 gp-->etap-->3pi0p-->6gp events allows a detailed study of the reaction dynamics. The gp-->etap differential cross sections were determined for 120 energy bins and the full range of the production angles. Our data show a dip near W = 1680 MeV in the total cross section caused by a substantial dip in eta production at forward angles. The data are compared to predictions of previous SAID and MAID partial-wave analyses and to thelatest SAID and MAID fits that have included our data.

121 data tables

Total cross section for the reaction GAMMA P --> ETA P.

Differential cross section for the reaction GAMMA P --> ETA P at a photon energy of 710.4 MeV. The errors in the table are statistical only and there is an overall systematic uncertainty of 4.3 PCT.

Differential cross section for the reaction GAMMA P --> ETA P at a photon energy of 714.5 MeV. The errors in the table are statistical only and there is an overall systematic uncertainty of 4.3 PCT.

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Cross sections and Rosenbluth separations in 1H(e, e'K+)Lambda up to Q2=2.35 GeV2

The Jefferson Lab Hall A collaboration Coman, M. ; Markowitz, P. ; Aniol, K.A. ; et al.
Phys.Rev.C 81 (2010) 052201, 2010.
Inspire Record 837422 DOI 10.17182/hepdata.54197

The kaon electroproduction reaction 1H(e,e'K+)Lambda was studied as a function of the virtual-photon four-momentum, Q2, total energy, W, and momentum transfer, t, for different values of the virtual- photon polarization parameter. Data were taken at electron beam energies ranging from 3.40 to 5.75 GeV. The center of mass cross section was determined for 21 kinematics corresponding to Q2 of 1.90 and 2.35 GeV2 and the longitudinal, sigmaL, and transverse, sigmaT, cross sections were separated using the Rosenbluth technique at fixed W and t. The separated cross sections reveal a flat energy dependence at forward kaon angles not satisfactorily described by existing electroproduction models. Influence of the kaon pole on the cross sections was investigated by adopting an off-shell form factor in the Regge model which better describes the observed energy dependence of sigmaT and sigmaL.

11 data tables

Measured values of the separated cross section at Q**2 = 2.35 GeV**2 and W = 1.85 GeV.. Errors contain both statistics and systematics.

Measured values of the separated cross section at Q**2 = 1.90 GeV**2.. Errors contain both statistics and systematics.

Measured values of the separated cross section at Q**2 = 2.35 GeV**2.. Errors contain both statistics and systematics.

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Differential cross sections for the reactions gamma p-> p eta and gamma p -> p eta-prime

The CLAS collaboration Williams, M. ; Krahn, Z. ; Applegate, D. ; et al.
Phys.Rev.C 80 (2009) 045213, 2009.
Inspire Record 830257 DOI 10.17182/hepdata.52983

High-statistics differential cross sections for the reactions gamma p -> p eta and gamma p -> p eta-prime have been measured using the CLAS at Jefferson Lab for center-of-mass energies from near threshold up to 2.84 GeV. The eta-prime results are the most precise to date and provide the largest energy and angular coverage. The eta measurements extend the energy range of the world's large-angle results by approximately 300 MeV. These new data, in particular the eta-prime measurements, are likely to help constrain the analyses being performed to search for new baryon resonance states.

104 data tables

Differential cross section for the W range 1.68 to 1.69 GeV.

Differential cross section for the W range 1.69 to 1.70 GeV.

Differential cross section for the W range 1.70 to 1.71 GeV.

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Neutral Pion Electroproduction in the Resonance Region at High $Q^2$

Villano, A.N. ; Stoler, P. ; Bosted, P.E. ; et al.
Phys.Rev.C 80 (2009) 035203, 2009.
Inspire Record 823260 DOI 10.17182/hepdata.54189

The process $ep \to e^{\prime}p^{\prime}\pi^0$ has been measured at $Q^2$ = 6.4 and 7.7 \ufourmomts in Jefferson Lab's Hall C. Unpolarized differential cross sections are reported in the virtual photon-proton center of mass frame considering the process $\gamma^{\ast}p \to p^{\prime}\pi^0$. Various details relating to the background subtractions, radiative corrections and systematic errors are discussed. The usefulness of the data with regard to the measurement of the electromagnetic properties of the well known $\Delta(1232)$ resonance is covered in detail. Specifically considered are the electromagnetic and scalar-magnetic ratios $R_{EM}$ and $R_{SM}$ along with the magnetic transition form factor $G_M^{\ast}$. It is found that the rapid fall off of the $\Delta(1232)$ contribution continues into this region of momentum transfer and that other resonances

125 data tables

Differential cross sections at Q**2=6.564 GeV**2, EPSILON=0.4523, W=1.112 GeV and COS(THETA(*))=-0.9 for the small SOS spectrometer.

Differential cross sections at Q**2=6.564 GeV**2, EPSILON=0.4523, W=1.112 GeV and COS(THETA(*))=-0.7 for the small SOS spectrometer.

Differential cross sections at Q**2=6.564 GeV**2, EPSILON=0.4523, W=1.112 GeV and COS(THETA(*))=-0.5 for the small SOS spectrometer.

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Exclusive measurement of two-pion production in the dd --> 4Hepipi reaction

Keleta, S. ; Bargholtz, Chr. ; Bashkanov, M. ; et al.
Nucl.Phys.A 825 (2009) 71-90, 2009.
Inspire Record 818215 DOI 10.17182/hepdata.52982

The results from the first kinematically complete measurement of the dd --> 4Hepipi reaction are reported. The aim was to investigate a long standing puzzle regarding the origin of the peculiar pipi-invariant mass distributions appearing in double pion production in light ion collisions, the so-called ABC effect. The measurements were performed at the incident deuteron energies of 712 MeV and 1029 MeV, with the WASA detector assembly at CELSIUS in Uppsala, Sweden. We report the observation of a characteristic enhancement at low pipi-invariant mass at 712 MeV, the lowest energy yet. At the higher energy, in addition to confirming previous experimental observations, our results reveal a strong angular dependence of the pions in the overall centre of mass system. The results are qualitatively reproduced by a theoretical model, according to which the ABC effect is described as resulting from a kinematical enhancement in the production of the pion pairs from two parallel and independent NN--> dpi sub-processes.

15 data tables

Total cross section for neutral and charged pion channels.

Invariant PI0 PI0 mass distribution at deuteron kinetic energy 1.029 GeV.

Invariant PI+ PI- mass distribution at deuteron kinetic energy 1.029 GeV.

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$\pi^+$ photoproduction on the proton for photon energies from 0.725 to 2.875 GeV

The CLAS collaboration Dugger, M. ; Ritchie, B.G. ; Ball, J.P. ; et al.
Phys.Rev.C 79 (2009) 065206, 2009.
Inspire Record 814847 DOI 10.17182/hepdata.51952

Differential cross sections for the reaction $\gamma p \to n \pi^+$ have been measured with the CEBAF Large Acceptance Spectrometer (CLAS) and a tagged photon beam with energies from 0.725 to 2.875 GeV. Where available, the results obtained here compare well with previously published results for the reaction. Agreement with the SAID and MAID analyses is found below 1 GeV. The present set of cross sections has been incorporated into the SAID database, and exploratory fits have been made up to 2.7 GeV. Resonance couplings have been extracted and compared to previous determinations. With the addition of these cross sections to the world data set, significant changes have occurred in the high-energy behavior of the SAID cross-section predictions and amplitudes.

11 data tables

Differential cross sections for incident photon energies 0.725, 0.775, 0.825and 0.875 GeV.

Differential cross sections for incident photon energies 0.925, 0.975, 1.025and 1.075 GeV.

Differential cross sections for incident photon energies 1.125, 1.175, 1.225and 1.275 GeV.

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Production of the omega meson in the pd --> 3He omega reaction at 1450 MeV and 1360 MeV

The CELSIUS/WASA collaboration Schonning, K. ; Bargholtz, Chr. ; Bashkanov, M. ; et al.
Phys.Rev.C 79 (2009) 044002, 2009.
Inspire Record 813975 DOI 10.17182/hepdata.52157

The production of $\omega$ mesons in the $pd \to{}^3$He$ \omega$ reaction has been studied at two energies near the kinematic threshold, $T_p=1450$ MeV and $T_p=1360$ MeV. The differential cross section was measured as a function of the $\omega$ cm angle at both energies over the whole angular range. Whereas the results at 1360 MeV are consistent with isotropy, strong rises are observed near both the forward and backward directions at 1450 MeV. Calculations made using a two-step model with an intermediate pion fail to reproduce the shapes of the measured angular distributions and also underestimate the total cross sections.

3 data tables

Total cross sections.

Differential cross section at 1450 MeV.

Differential cross section at 1360 MeV.