HEPData Search

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Antiproton-proton elastic scattering from 1.51–2.90 GeV/ c

Parker, D.L. ; Oh, B.Y. ; Smith, G.A. ; et al.

Nucl.Phys.B 32 (1971) 29-44, 1971.

Inspire Record 1392679 DOI 10.17182/hepdata.814

In a bubble chamber experiment, we have measured p p elastic scattering at nine momenta in the range 1.51–2.90 GeV/ c . The extrapolation of the small angle region to t = 0 is discussed and compared with results of other experiments. The differential cross sections are fitted to an adaptation of the Frahn-Venter optical model and also compared to Regge-pole model predictions.

19 data tables

Table 1

'1'. '2'. '3'.

Table 2

'1'. '3'.

Table 3

'2'.

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The Charge Form Factor of the Proton at a Momentum Transfer of 75 F$^-^2$

Bartel, W. ; Dudelzak, B. ; Krehbiel, H. ; et al.

Phys.Lett.B 25 (1967) 236-237, 1967.

Inspire Record 1333753 DOI 10.17182/hepdata.29448

The proton form factors GE(q2) and GM(q2) are determined at q2 = 75fm−2.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Electroproduction of $\phi(1020)$ mesons at $1.4\leq Q^2\leq$ 3.8 GeV$^2$ measured with the CLAS spectrometer

The CLAS collaboration Santoro, J.P. ; Smith, E.S. ; Garc con, M. ; et al.

Phys.Rev.C 78 (2008) 025210, 2008.

Inspire Record 781974 DOI 10.17182/hepdata.50913

Electroproduction of exclusive $\phi$ vector mesons has been studied with the CLAS detector in the kinematical range $1.6\leq Q^2\leq 3.8$ GeV$^{2}$, $0.0\leq t^{\prime}\leq 3.6$ GeV$^{2}$, and $2.0\leq W\leq 3.0$ GeV. The scaling exponent for the total cross section as $1/(Q^2+M_{\phi}^2)^n$ was determined to be $n=2.49\pm 0.33$. The slope of the four-momentum transfer $t'$ distribution is $b_{\phi}=0.98 \pm 0.17$ GeV$^{-2}$. The data are consistent with the assumption of s-channel helicity conservation (SCHC). Under this assumption, we determine the ratio of longitudinal to transverse cross sections to be $R=0.86 \pm 0.24$. A 2-gluon exchange model is able to reproduce the main features of the data.

5 data tables

Table 1

Axis error includes +- 18.6/18.6 contribution.

Table 2

Axis error includes +- 18.6/18.6 contribution.

Table 3

Axis error includes +- 18.6/18.6 contribution.

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Determination of the Charged Pion Form Factor at Q2=1.60 and 2.45 (GeV/c)2

The Jefferson Lab F(pi)-2 collaboration Horn, T. ; Aniol, K. ; Arrington, J. ; et al.

Phys.Rev.Lett. 97 (2006) 192001, 2006.

Inspire Record 721062 DOI 10.17182/hepdata.31560

The H(e,e'pi+)n cross section was measured at four-momentum transfers of Q2=1.60 and 2.45 GeV2 at an invariant mass of the photon nucleon system of W=2.22 GeV. The charged pion form factor (F_pi) was extracted from the data by comparing the separated longitudinal pion electroproduction cross section to a Regge model prediction in which F_pi is a free parameter. The results indicate that the pion form factor deviates from the charge-radius constrained monopole form at these values of Q2 by one sigma, but is still far from its perturbative Quantum Chromo-Dynamics prediction.

3 data tables

Table 1

Separated cross sections at mean Q**2 of 1.60 GeV**2.

Table 2

Separated cross sections at mean Q**2 of 2.45 GeV**2.

Table 3

Extracted values of the charged pion form-factor. Errors are the statistical and experimental systematics combined in quadrature.

Cross section measurements of charged pion photoproduction in hydrogen and deuterium from 1.1-GeV to 5.5-GeV.

The Jefferson Lab Hall A & Jefferson Lab E94-104 collaborations Zhu, L.Y. ; Arrington, J. ; Averett, T. ; et al.

Phys.Rev.C 71 (2005) 044603, 2005.

Inspire Record 659852 DOI 10.17182/hepdata.31680

The differential cross section for the gamma +n --> pi- + p and the gamma + p --> pi+ n processes were measured at Jefferson Lab. The photon energies ranged from 1.1 to 5.5 GeV, corresponding to center-of-mass energies from 1.7 to 3.4 GeV. The pion center-of-mass angles varied from 50 degree to 110 degree. The pi- and pi+ photoproduction data both exhibit a global scaling behavior at high energies and high transverse momenta, consistent with the constituent counting rule prediction and the existing pi+ data. The data suggest possible substructure of the scaling behavior, which might be oscillations around the scaling value. The data show an enhancement in the scaled cross section at center-of-mass energy near 2.2 GeV. The differential cross section ratios at high energies and high transverse momenta can be described by calculations based on one-hard-gluon-exchange diagrams.

14 data tables

Table 1

Differential cross section for the process GAMMA N --> PI- P for an incident electron energy of 5.614 GeV.

Table 2

Differential cross section for the process GAMMA N --> PI- P for an incident electron energy of 4.236 GeV.

Table 3

Differential cross section for the process GAMMA N --> PI- P for an incident electron energy of 3.400 GeV.

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Cross section measurement of charged pion photoproduction from hydrogen and deuterium.

The Jefferson Lab Hall A collaboration Zhu, L.Y. ; Arrington, J. ; Averett, T. ; et al.

Phys.Rev.Lett. 91 (2003) 022003, 2003.

Inspire Record 601768 DOI 10.17182/hepdata.31722

We have measured the differential cross section for the gamma n --> pi- p and gamma p --> pi+ n reactions at center of mass angle of 90 degree in the photon energy range from 1.1 to 5.5 GeV at Jefferson Lab (JLab). The data at photon energies greater than 3.3 GeV exhibit a global scaling behavior for both pi- and pi+ photoproduction, consistent with the constituent counting rule and the existing pi+ photoproduction data. Possible oscillations around the scaling value are suggested by these new data The data show enhancement in the scaled cross section at a center-of-mass energy near 2.2 GeV. The cross section ratio of exclusive pi- to pi+ photoproduction at high energy is consistent with the prediction based on one-hard-gluon-exchange diagrams.

1 data table

Table 1

Differential cross section at THETA(CM) = 90 degrees.

A Search for weakly interacting neutral particles in missing energy events in 450-GeV/c p N collisions

The HELIOS collaboration Åkesson, T. ; Almehed, S. ; Angelis, A.L. S. ; et al.

Z.Phys.C 52 (1991) 219-226, 1991.

Inspire Record 302922 DOI 10.17182/hepdata.15014

We have measured the inclusive cross-section as a function of missing energy, due to the production of neutrinos or new weakly interacting neutral particles in 450 GeV/c proton-nucleus collisions, using calorimetric measurements of visible event energy. Upper limits are placed on the production of new particles as a function of their energy. These upper limits are typically an order

9 data tables

Table 1

Differential single diffraction cross section.

Table 2

Differential single diffraction cross section.

Table 3

Differential single diffraction cross section.

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A Measurement of the Energy Dependence of Elastic $\pi p$ and $p p$ Scattering at Large Angles

Jenkins, K.A. ; Price, L.E. ; Klem, R. ; et al.

Phys.Rev.Lett. 40 (1978) 425, 1978.

Inspire Record 6233 DOI 10.17182/hepdata.3359

We have measured π±p and pp elastic differential cross sections in the range |cosθc.m.|<0.35 for incident momenta from 2 to 9.7 GeV/c for π−p and pp and from 2 to 6.3 GeV/c for π+p. We find that the fixed-c.m.-angle πp differential cross sections cannot be described as simple functions of s. The data are compared to the energy and angular dependence predicted by the constituent model of Gunion, Brodsky, and Blankenbecler.

56 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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A Study of the Reactions pi+ p --> (rho0, omega) Delta++ at 13-GeV/c

Gaidos, J.A. ; Hirata, A.A. ; DeBonte, R.J. ; et al.

Nucl.Phys.B 72 (1974) 253-282, 1974.

Inspire Record 763 DOI 10.17182/hepdata.32316

Cross sections, differential cross sections, density matrix elements and statistical tensors are given for the reactions π + p → ( ϱ 0 , ω ) Δ ++ at 13.2 GeV/ c . A discussion of the results in terms of particle exchanges, quark model or dipole coupling constraints, and the equal phase hypothesis is presented in some detail for the high statistics ϱ 0 Δ ++ channel.

10 data tables

Table 1

BREIT-WIGNER FITS WHICH CORRECT FOR RESONANCE TAILS AND BACKGROUNDS.

Table 2

No description provided.

Table 3

JACKSON FRAME DENSITY MATRIX ELEMENTS.