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Studies of $\bar{p} p \to \bar{n} n$ and $\bar{n} p$ Annihilation at Incident Momenta of 700-{MeV}/$c$ and 760-{MeV}/$c$

The Bombay-Chandigarh-Jammu-Tokyo collaboration Banerjee, S. ; Ganguli, S.N. ; Gurtu, A. ; et al.

Z.Phys.C 28 (1985) 163, 1985.

Inspire Record 217418 DOI 10.17182/hepdata.1974

Results are presented on the charge exchange reaction$\bar pp \to \bar nn$ and$\bar np$ annihilations from bubble chamber exposures to antiproton beam of momenta 700 and 760 MeV/c. The differential cross section of$\bar pp \to \bar nn$ shows a forward spike followed by a clear dip bump structure. Total annihilation cross section of$\bar np$ for average$\bar n$ momentum of 700 MeV/c has been evaluated to be 55.4±2.2 mb. The multiplicity, Feynmanx andpT2 distributions for inclusive charged pions in$\bar pp$ and$\bar np$ annihilations are found to be similar. The emission of charged pions from$\bar np$ annihilations are found to be consistent with thermodynamic models with temperature ∼110 MeV.

1 data table match query

Table 1

No description provided.

Single-Pion Production in pp Collisions at 0.95-GeV/c (I)

The COSY-TOF collaboration El-Samad, S.Abd ; Bilger, R. ; Brinkmann, K. -Th. ; et al.

Eur.Phys.J.A 30 (2006) 443-453, 2006.

Inspire Record 725793 DOI 10.17182/hepdata.43429

The single-pion production reactions $pp\to d\pi^+$, $pp\to np\pi^+$ and $pp\to pp\pi^0$ were measured at a beam momentum of 0.95 GeV/c ($T_p \approx$ 400 MeV) using the short version of the COSY-TOF spectrometer. The implementation of a central calorimeter provided particle identification, energy determination and neutron detection in addition to time-of-flight and angle measurements. Thus all pion production channels were recorded with 1-4 overconstraints. The total and differential cross sections obtained are compared to previous data and theoretical calculations. Main emphasis is put on the discussion of the $pp\pi^0$ channel, where we obtain angular distributions different from previous experimental results, however, partly in good agreement with recent phenomenological and theoretical predictions. In particular we observe very large anisotropies for the $\pi^0$ angular distributions in the kinematical region of small relative proton momenta revealing there a dominance of proton spinflip transitions associated with $\pi^0$ $s$- and $d$-partial waves and emphasizing the important role of $\pi^0$ d-waves.

1 data table match query

Table 2

Measured angular distribution for elastic P P scattering in the CM system normalised to the data in the SAID database (Arndt et al. PR C62,034005(2000). This measurement is made to determine the luminosity.

Measurements of electron proton elastic cross sections for 0.4-(GeV/c)2 < Q2 < 5.5-(GeV/c)**2.

The E94110 collaboration Christy, M.E. ; Ahmidouch, A. ; Armstrong, C.S. ; et al.

Phys.Rev.C 70 (2004) 015206, 2004.

Inspire Record 643262 DOI 10.17182/hepdata.31763

We report on precision measurements of the elastic cross section for electron-proton scattering performed in Hall C at Jefferson Lab. The measurements were made at 28 unique kinematic settings covering a range in momentum transfer of 0.4 $<$ $Q^2$ $<$ 5.5 $(\rm GeV/c)^2$. These measurements represent a significant contribution to the world's cross section data set in the $Q^2$ range where a large discrepancy currently exists between the ratio of electric to magnetic proton form factors extracted from previous cross section measurements and that recently measured via polarization transfer in Hall A at Jefferson Lab.

7 data tables match query

Table 1

Measured values of the electron-proton elastic cross section for beam energy 1.148 GeV.

Table 2

Measured values of the electron-proton elastic cross section for beam energy 1.882 GeV.

Table 3

Measured values of the electron-proton elastic cross section for beam energy 2.235 GeV.

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Compton scattering cross section on the proton at high momentum transfer.

The Hall A collaboration Danagoulian, A. ; Mamyan, V.H. ; Roedelbronn, M. ; et al.

Phys.Rev.Lett. 98 (2007) 152001, 2007.

Inspire Record 743383 DOI 10.17182/hepdata.31472

Cross-section values for Compton scattering on the proton were measured at 25 kinematic settings over the range s = 5-11 and -t = 2-7 GeV2 with statistical accuracy of a few percent. The scaling power for the s-dependence of the cross section at fixed center of mass angle was found to be 8.0 +/ 0.2, strongly inconsistent with the prediction of perturbative QCD. The observed cross-section values are in fair agreement with the calculations using the handbag mechanism, in which the external photons couple to a single quark.

4 data tables match query

Table 1

Cross section of proton Compton Scattering at centre of mass energy squared of 4.82 GeV.

Table 2

Cross section of proton Compton Scattering at centre of mass energy squared of 6.79 GeV.

Table 3

Cross section of proton Compton Scattering at centre of mass energy squared of 8.90 GeV.

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Polarization transfer in proton Compton scattering at high momentum transfer.

The Jefferson Lab Hall A collaboration Hamilton, D.J. ; Mamyan, V.H. ; Aniol, K.A. ; et al.

Phys.Rev.Lett. 94 (2005) 242001, 2005.

Inspire Record 660894 DOI 10.17182/hepdata.19389

Compton scattering from the proton was investigated at s=6.9 (GeV/c)**2 and \t=-4.0 (GeV/c)**2 via polarization transfer from circularly polarized incident photons. The longitudinal and transverse components of the recoil proton polarization were measured. The results are in excellent agreement with a prediction based on a reaction mechanism in which the photon interacts with a single quark carrying the spin of the proton and in disagreement with a prediction of pQCD based on a two-gluon exchange mechanism.

1 data table match query

Table 1

Polarization transfer parameters.

A study of Sigma+ p elastic scattering in the region of 300-MeV/c <= p(Sigma) <= 600-MeV/c with a scintillating fiber target.

The KEK-PS E-251 collaboration Ahn, J.K. ; Bassalleck, B. ; Chung, M.S. ; et al.

Nucl.Phys.A 648 (1999) 263-279, 1999.

Inspire Record 453129 DOI 10.17182/hepdata.38435

Σ + p elastic scattering has been studied using a scintillating fiber block (SCIFI) which served as a target for the production of Σ + hyperons as well as for subsequent Σ + scattering on hydrogen. A new technique for the analysis of the hyperon-nucleon scattering in the SCIFI has been developed and established. In this paper, Σ + p elastic scattering events have been identified in the Σ + momentum range of 300–600 MeV/ c , and differential cross sections have been obtained at two angles. The results are compared with various theoretical baryon-baryon interaction models.

1 data table match query

Table 1

No description provided.

Differential Cross-sections of Proton Compton Scattering at Photon Laboratory Energies Between 1.2-{GeV} and 1.7-{GeV}

Duda, J. ; Hofner, F.W. ; Jung, M. ; et al.

Z.Phys.C 17 (1983) 319, 1983.

Inspire Record 182590 DOI 10.17182/hepdata.50210

Differential cross sections of proton Compton scattering have been measured at the Bonn 2.5 GeV synchrotron. The experiment covers photon laboratory energies between 1.2 GeV and 1.7 GeV and the square of the four-momentum transfer ranges fromt=−0.17 GeV2 to −0.98GeV2 corresponding to c.m. scattering angles between 35° and 80°. The cross sections exhibit a forward peak followed by a monotone fall-off up to the largest measured |t|-values. Fits of the formdσ/dt=A·exp(Bt) to the data points with |t|≦0.5 GeV2 yield forward cross sectionsA, which are consistent with the 0° cross sections calculated from the measured total photon-proton cross section. The average slope isB=5.6±0.14 GeV2.

13 data tables match query

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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DCS for π − p elastic scattering from 1.2 to 3.0 GeV/ c and phase shift analysis

Aplin, P.S. ; Cowan, I.M. ; Gibson, W.M. ; et al.

Nucl.Phys.B 32 (1971) 253-284, 1971.

Inspire Record 1104030 DOI 10.17182/hepdata.69638

Differential cross sections have been measured for π − p elastic scattering at laboratory momenta in the range 1.2 to 3.0 GeV/ c for the c.m. range 0.97 > cos θ ∗ > −0.98 . The corresponding mass range is 1.78 to 2.56 GeV/ c 2 . The data was obtained from a counter experiment in which the scattered pions and protons were detected in coincidence by arrays of scintillation counters.

31 data tables match query

Table 1

No description provided.

Table 2

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Table 3

No description provided.