Date

Subject_areas

Photoproduction of $\Lambda$ and $\Sigma^{0}$ hyperons off protons with linearly polarized photons at $E_{\gamma} = 1.5-3.0$ GeV

The LEPS collaboration Shiu, S.H. ; Kohri, H. ; Chang, W.C. ; et al.
Phys.Rev. C97 (2018) 015208, 2018.
Inspire Record 1636280 DOI 10.17182/hepdata.81998

We report the measurement of the γp→K+Λ and γp→K+Σ0 reactions at SPring-8. The differential cross sections and photon-beam asymmetries are measured at forward K+ production angles using linearly polarized tagged-photon beams in the range of Eγ=1.5–3.0 GeV. With increasing photon energy, the cross sections for both γp→K+Λ and γp→K+Σ0 reactions decrease slowly. Distinct narrow structures in the production cross section have not been found at Eγ=1.5–3.0 GeV. The forward peaking in the angular distributions of cross sections, a characteristic feature of t-channel exchange, is observed for the production of Λ in the whole observed energy range. A lack of similar feature for Σ0 production reflects a less dominant role of t-channel contribution in this channel. The photon-beam asymmetries remain positive for both reactions, suggesting the dominance of K* exchange in the t channel. These asymmetries increase gradually with the photon energy, and have a maximum value of +0.6 for both reactions. Comparison with theoretical predictions based on the Regge trajectory in the t channel and the contributions of nucleon resonances indicates the major role of t-channel contributions as well as non-negligible effects of nucleon resonances in accounting for the reaction mechanism of hyperon photoproduction in this photon energy regime.

46 data tables

Differential cross sections for the GAMMA P --> K+ LAMBDA reaction as a function of photon energy Egamma for the kaon c.m. production polar angle 0.6 < cos(theta) < 0.7.

Differential cross sections for the GAMMA P --> K+ LAMBDA reaction as a function of photon energy Egamma for the kaon c.m. production polar angle 0.7 < cos(theta) < 0.8.

Differential cross sections for the GAMMA P --> K+ LAMBDA reaction as a function of photon energy Egamma for the kaon c.m. production polar angle 0.8 < cos(theta) < 0.9.

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PHOTOPRODUCTION OF K+ HYPERON FROM HYDROGEN AND DEUTERIUM AT 11-GeV

Boyarski, A. ; Diebold, Robert E. ; Ecklund, Stanley D. ; et al.
Phys.Lett. B34 (1971) 547-550, 1971.
Inspire Record 60853 DOI 10.17182/hepdata.5801
4 data tables

No description provided.

No description provided.

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Measurements of Exclusive Photoproduction Processes at Large Values of t and u from 4-GeV to 7.5-GeV

Anderson, Robert L. ; Gustavson, D. ; Ritson, D. ; et al.
Phys.Rev. D14 (1976) 679, 1976.
Inspire Record 108061 DOI 10.17182/hepdata.4592
18 data tables

No description provided.

No description provided.

No description provided.

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ASYMMETRY IN pi+ PHOTOPRODUCTION FROM A POLARIZED TARGET AT 5-GeV AND 16-GeV

Morehouse, Charles C. ; Borghini, M. ; Chamberlain, Owen ; et al.
Phys.Rev.Lett. 25 (1970) 835, 1970.
Inspire Record 60947 DOI 10.17182/hepdata.3373
5 data tables

No description provided.

No description provided.

No description provided.

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STUDY OF THE BACKWARD PHOTOPRODUCTION REACTION gamma p ---> K+ lambda BETWEEN 1-GeV AND 2-GeV

Decamp, D. ;
PhD Thesis, 1971.
Inspire Record 1086457 DOI 10.17182/hepdata.70365
38 data tables

No description provided.

No description provided.

No description provided.

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Differential cross section and recoil polarization measurements for the gamma p to K+ Lambda reaction using CLAS at Jefferson Lab

The CLAS collaboration McCracken, M.E. ; Bellis, M. ; Meyer, C.A. ; et al.
Phys.Rev. C81 (2010) 025201, 2010.
Inspire Record 840934 DOI 10.17182/hepdata.54967

We present measurements of the differential cross section and Lambda recoil polarization for the gamma p to K+ Lambda reaction made using the CLAS detector at Jefferson Lab. These measurements cover the center-of-mass energy range from 1.62 to 2.84 GeV and a wide range of center-of-mass K+ production angles. Independent analyses were performed using the K+ p pi- and K+ p (missing pi -) final-state topologies/ results from these analyses were found to exhibit good agreement. These differential cross section measurements show excellent agreement with previous CLAS and LEPS results and offer increased precision and a 300 MeV increase in energy coverage. The recoil polarization data agree well with previous results and offer a large increase in precision and a 500 MeV extension in energy range. The increased center-of-mass energy range that these data represent will allow for independent study of non-resonant K+ Lambda photoproduction mechanisms at all production angles.

241 data tables

Differential cross section as a function of COS(THETA(K)) for the centre-of-mass range 1.62-1.63 GeV.

Differential cross section as a function of COS(THETA(K)) for the centre-of-mass range 1.63-1.64 GeV.

Differential cross section as a function of COS(THETA(K)) for the centre-of-mass range 1.64-1.65 GeV.

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Measurement of the polarized gamma p ---> K+ Lambda reaction at backward angles

The LEPS collaboration Hicks, K. ; Mibe, T. ; Sumihama, M. ; et al.
Phys.Rev. C76 (2007) 042201, 2007.
Inspire Record 766880 DOI 10.17182/hepdata.25090
5 data tables

Differential cross sections as a function of the Mandelstam variable U for photon beam energy 1.5 to 1.8 GeV.

Differential cross sections as a function of the Mandelstam variable U for photon beam energy 1.8 to 2.1 GeV.

Differential cross sections as a function of the Mandelstam variable U for photon beam energy 2.1 to 2.4 GeV.

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First measurement of beam-recoil observables C(x) and C(z) in hyperon photoproduction

The CLAS collaboration Bradford, R.K. ; Schumacher, R.A. ; Adams, G. ; et al.
Phys.Rev. C75 (2007) 035205, 2007.
Inspire Record 732402 DOI 10.17182/hepdata.31496

Spin transfer from circularly polarized real photons to recoiling hyperons has been measured for the reactions $\vec\gamma + p \to K^+ + \vec\Lambda$ and $\vec\gamma + p \to K^+ + \vec\Sigma^0$. The data were obtained using the CLAS detector at Jefferson Lab for center-of-mass energies $W$ between 1.6 and 2.53 GeV, and for $-0.85<\cos\theta_{K^+}^{c.m.}< +0.95$. For the $\Lambda$, the polarization transfer coefficient along the photon momentum axis, $C_z$, was found to be near unity for a wide range of energy and kaon production angles. The associated transverse polarization coefficient, $C_x$, is smaller than $C_z$ by a roughly constant difference of unity. Most significantly, the {\it total} $\Lambda$ polarization vector, including the induced polarization $P$, has magnitude consistent with unity at all measured energies and production angles when the beam is fully polarized. For the $\Sigma^0$ this simple phenomenology does not hold. All existing hadrodynamic models are in poor agreement with these results.

34 data tables

Coefficients Cx and Cz for the reaction GAMMA P --> K+ LAMBDA for incident energy = 1.032 GeV and W = 1.679 GeV.

Coefficients Cx and Cz for the reaction GAMMA P --> K+ LAMBDA for incident energy = 1.132 GeV and W = 1.734 GeV.

Coefficients Cx and Cz for the reaction GAMMA P --> K+ LAMBDA for incident energy = 1.232 GeV and W = 1.787 GeV.

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The Polarized-gamma p ---> K+ Lambda and polarized-gamma p ---> K+ Sigma0 reactions at forward angles with photon energies from 1.5-GeV to 2.4-GeV

The LEPS collaboration Sumihama, M. ; Ahn, J.K. ; Akimune, H. ; et al.
Phys.Rev. C73 (2006) 035214, 2006.
Inspire Record 701097 DOI 10.17182/hepdata.41824

Differential cross sections and photon beam asymmetries for the gamma p rightarrow K+ Lambda and gamma p rightarrow K+ Sigma0 reactions have been measured in the photon energy range from 1.5 GeV to 2.4 GeV and in the angular range from Theta_{cm} = 0 to 60 of the K+ scattering angle in the center of mass system at the SPring-8/LEPS facility. The photon beam asymmetries for both the reactions have been found to be positive and to increase with the photon energy. The measured differential cross sections agree with the data measured by the CLAS collaboration at cosTheta_{cm}<0.9 within the experimental uncertainties, but the discrepancy with the SAPHIR data for the K+Lambda reaction is large at cosTheta_{cm}>0.9. In the K+Lambda reaction, the resonance-like structure found in the CLAS and SAPHIR data at W=1.96 GeV is confirmed. The differential cross sections at forward angles suggest a strong K-exchange contribution in the t-channel for the K+Lambda reaction, but not for the K+Sigma0 reaction.

14 data tables

Photon beam asymmetries for the two reactions as a function of CM angle for photon beam energy 1.55 GeV (W=1.947 GeV).

Photon beam asymmetries for the two reactions as a function of CM angle for photon beam energy 1.65 GeV (W=1.994 GeV).

Photon beam asymmetries for the two reactions as a function of CM angle for photon beam energy 1.75 GeV (W=2.041 GeV).

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Measurement of gamma p ---> K+ Lambda and gamma p ---> K+ Sigma0 at photon energies up to 2.6-GeV

Glander, K.H. ; Barth, J. ; Braun, W. ; et al.
Eur.Phys.J. A19 (2004) 251-273, 2004.
Inspire Record 626695 DOI 10.17182/hepdata.51677

The reactions gamma p --> K+ Lambda and gamma p --> K+ Sigma0 were measured in the energy range from threshold up to a photon energy of 2.6 GeV. The data were taken with the SAPHIR detector at the electron stretcher facility, ELSA. Results on cross sections and hyperon polarizations are presented as a function of kaon production angle and photon energy. The total cross section for Lambda production rises steeply with energy close to threshold, whereas the Sigma0 cross section rises slowly to a maximum at about E_gamma = 1.45 GeV. Cross sections together with their angular decompositions into Legendre polynomials suggest contributions from resonance production for both reactions. In general, the induced polarization of Lambda has negative values in the kaon forward direction and positive values in the backward direction. The magnitude varies with energy. The polarization of Sigma0 follows a similar angular and energy dependence as that of Lambda, but with opposite sign.

24 data tables

Differential cross sections for the reaction GAMMA P --> K+ LAMBDA in the energy region 0.9 to 1.0 GeV.

Differential cross sections for the reaction GAMMA P --> K+ LAMBDA in the energy region 1.0 to 1.2 GeV.

Differential cross sections for the reaction GAMMA P --> K+ LAMBDA in the energy region 1.2 to 1.4 GeV.

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Measurement of gamma p --> K+ Lambda and gamma p --> K+ Sigma0 at photon energies up to 2-GeV

The SAPHIR collaboration Tran, M.Q. ; Barth, J. ; Bennhold, C. ; et al.
Phys.Lett. B445 (1998) 20-26, 1998.
Inspire Record 483236 DOI 10.17182/hepdata.27074
10 data tables

Total cross section for the reaction GAMMA P --> K+ LAMBDA.

Total cross section for the reaction GAMMA P --> K+ SIGMA0.

Differential cross section for the reaction GAMMA P --> K+ LAMBDA in the GAMMA energy range 0.90 to 1.10 GeV in three energy bins.

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Beam polarization asymmetries for the p(gamma, K+) Lambda and p(gamma, K+) Sigma0 reactions at E(gamma) = 1.5 Gev - 2.4 GeV

The LEPS collaboration Zegers, R.G.T. ; Sumihama, M. ; Ahn, D.S. ; et al.
Phys.Rev.Lett. 91 (2003) 092001, 2003.
Inspire Record 613016 DOI 10.17182/hepdata.31708

Beam polarization asymmetries for the p(gamma,K+)Lambda and p(gamma,K+)sigma0 reactions are measured for the first time for Egamma=1.5-2.4 GeV and 0.6<cos(theta_cm(K+))<1.0 by using linearly polarized photons at the Laser-Electron-Photon facility at SPring-8 (LEPS). The observed asymmetries are positive and gradually increase with rising photon energy. The data are not consistent with theoretical predictions based on tree-level effective Lagrangian approaches. Including the new results in the development of the models is, therefore, crucial for understanding the reaction mechanism and to test the presence of baryon resonances which are predicted in quark models but are sofar undiscovered.

18 data tables

Measured beam asymmetries for the reaction GAMMA P --> K+ LAMBDA for beam energy 1.5 to 1.6.

Measured beam asymmetries for the reaction GAMMA P --> K+ LAMBDA for beam energy 1.6 to 1.7.

Measured beam asymmetries for the reaction GAMMA P --> K+ LAMBDA for beam energy 1.7 to 1.8.

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Measurement of gamma p ---> K+ Lambda and gamma p ---> K+ Sigma0 at photon energies up to 1.47-GeV

Bockhorst, M. ; Burbach, G. ; Burgwinkel, R. ; et al.
Z.Phys. C63 (1994) 37-47, 1994.
Inspire Record 380478 DOI 10.17182/hepdata.14114
8 data tables

Differential cross sections.

Total cross sections.

Differential cross sections.

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Photoproduction of k+ mesons and polarization of lambda0 hyperons in the 1-gev range

Fujii, T. ; Imanishi, A. ; Iwata, S. ; et al.
Phys.Rev. D2 (1970) 439-448, 1970.
Inspire Record 61523 DOI 10.17182/hepdata.24271
3 data tables

No description provided.

No description provided.

No description provided.


Photoproduction of k+ lambda and k+ sigma0 from hydrogen between 1.3 and 1.45 gev

Bleckmann, A. ; Herda, S. ; Opara, U. ; et al.
Z.Phys. 239 (1970) 1-15, 1970.
Inspire Record 63868 DOI 10.17182/hepdata.16698
4 data tables

No description provided.

No description provided.

No description provided.

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Recoil polarization in K$^+ \Lambda$ photoproduction at 5 gev

Vogel, G. ; Burfeindt, H. ; Buschhorn, G. ; et al.
Phys.Lett. B40 (1972) 513-516, 1972.
Inspire Record 75679 DOI 10.17182/hepdata.28291
1 data table

No description provided.


Photoproduction of k+ lambda and k+ sigma0 in hydrogen between 1.19 and 1.68 gev

Goeing, H. ; Schorsch, W. ; Tietge, J. ; et al.
Nucl.Phys. B26 (1971) 121-133, 1971.
Inspire Record 68818 DOI 10.17182/hepdata.33752
2 data tables

No description provided.

No description provided.


A Study of Charged Pseudoscalar Meson Photoproduction From Hydrogen and Deuterium With 16-{GeV} Linearly Polarized Photons

Quinn, D.J. ; Rutherfoord, J.P. ; Shupe, M.A. ; et al.
Phys.Rev. D20 (1979) 1553, 1979.
Inspire Record 140543 DOI 10.17182/hepdata.24208
7 data tables

ASYMMETRIES AND DIFFERENTIAL CROSS SECTIONS FOR PION-NUCLEON PHOTOPRODUCTION WERE FIRST PUBLISHED IN D. J. SHERDEN ET AL., PRL 30, 1230 (1973) AND PRL 31, 667 (1973) (ERRATUM). THESE SLIGHTLY REVISED NUMBERS ARE INCLUDED IN THE RECORD OF THE 1973 PAPER.

No description provided.

No description provided.

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Photoproduction of k+ lambda0 and k+ sigma0 from hydrogen at constant momentum transfer t between 1.05 and 2.2 gev

Feller, P. ; Menze, D. ; Opara, U. ; et al.
Nucl.Phys. B39 (1972) 413-420, 1972.
Inspire Record 75243 DOI 10.17182/hepdata.32925
2 data tables

AT CONSTANT MOMENTUM TRANSFER OF -T = 0.147 GEV**2.

AT APPROXIMATELY CONSTANT MOMENTUM TRANSFER OF -T = 0.17 GEV**2.


Photoproduction of K+ Lambda0 on Polarized Protons

Althoff, K.H. ; Gies, M. ; Herr, H. ; et al.
Nucl.Phys. B137 (1978) 269-275, 1978.
Inspire Record 135345 DOI 10.17182/hepdata.35095
1 data table

5 PCT TARGET POLARIZATION UNCERTAINTY INCLUDED IN QUOTED ERRORS.


Measurement of the Polarization of the Lambda0 in the Reaction gamma p --> K+ Lambda0 in the Resonance Region

Haas, R. ; Miczaika, T. ; Opara, U. ; et al.
Nucl.Phys. B137 (1978) 261-268, 1978.
Inspire Record 135344 DOI 10.17182/hepdata.35123
1 data table

No description provided.


Polarized Photon Asymmetries in K+ Photoproduction at 16-GeV

Quinn, D.J. ; Rutherfoord, J.P. ; Shupe, M.A. ; et al.
Phys.Rev.Lett. 34 (1975) 543, 1975.
Inspire Record 100595 DOI 10.17182/hepdata.21241
1 data table

No description provided.


PHOTOPRODUCTION OF K+ LAMBDA AND K+ SIGMA0 FROM HYDROGEN FROM 5-GeV to 16-Gev

Boyarski, A. ; Bulos, F. ; Busza, W. ; et al.
Phys.Rev.Lett. 22 (1969) 1131-1133, 1969.
Inspire Record 54849 DOI 10.17182/hepdata.3394
9 data tables
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Photoproduction cross sections for pi+ and K+ mesons at 3.4 to 4.0 GeV and their comparison with SU(3)

Elings, V.B. ; Cohen, K.J. ; Garelick, D.A. ; et al.
Phys.Rev. 156 (1967) 1433-1443, 1967.
Inspire Record 51624 DOI 10.17182/hepdata.406
6 data tables

No description provided.

No description provided.

No description provided.

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Lambda Polarization at 90-degrees in K+Lambda Photoproduction

Groom, D.E. ; Marshall, J.H. ;
Phys.Rev. 159 (1967) 1213-1219, 1967.
Inspire Record 52237 DOI 10.17182/hepdata.26579
2 data tables

No description provided.

No description provided.