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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First Measurement of the Muon Neutrino Charged Current Single Pion Production Cross Section on Water with the T2K Near Detector

Abe, K. ; Andreopoulos, C. ; Antonova, M. ; et al.
No Journal Information, 2016.
Inspire Record 1465650 DOI 10.17182/hepdata.73182

The T2K off-axis near detector, ND280, is used to make the first differential cross section measurements of muon neutrino charged current single positive pion production on a water target at energies ${\sim}0.8$~GeV. The differential measurements are presented as a function of muon and pion kinematics, in the restricted phase-space defined by $p_{\pi^+}>200$MeV/c, $p_{\mu^-}>200$MeV/c, $\cos \theta_{\pi^+}>0.3$ and $\cos \theta_{\mu^-}>0.3$. The total flux integrated $\nu_\mu$ charged current single positive pion production cross section on water in the restricted phase-space is measured to be $\langle\sigma\rangle_\phi=4.25\pm0.48~(\mathrm{stat})\pm1.56~(\mathrm{syst})\times10^{-40}~\mathrm{cm}^{2}/\mathrm{nucleon}$. The total cross section is consistent with the NEUT prediction ($5.03\times10^{-40}~\mathrm{cm}^{2}/\mathrm{nucleon}$) and 2$\sigma$ lower than the GENIE prediction ($7.68\times10^{-40}~\mathrm{cm}^{2}/\mathrm{nucleon}$). The differential cross sections are in good agreement with the NEUT generator. The GENIE simulation reproduces well the shapes of the distributions, but over-estimates the overall cross section normalization.

8 data tables

Total $\nu_\mu$ CC1$\pi^+$ cross section on water in the reduced phase-space of $p_{\pi^+} > 200$ MeV/$c$, $p_\mu > 200$ MeV/c, $\cos(\theta_{\pi^+}) > 0.3$ and $\cos(\theta_\mu) > 0.3$. The T2K data point is placed at the $\nu_\mu$ flux mean energy.

Unfolded $\nu_\mu$ CC1$\pi^+$ differential cross section as a function of $p_\pi$ in the reduced phase-space of $p_{\pi^+} > 200$ MeV/$c$, $p_\mu > 200$ MeV/c, $\cos(\theta_{\pi^+}) > 0.3$ and $\cos(\theta_\mu) > 0.3$.

Unfolded $\nu_\mu$ CC1$\pi^+$ differential cross section as a function of $\cos\theta_\pi$ in the reduced phase-space of $p_{\pi^+} > 200$ MeV/$c$, $p_\mu > 200$ MeV/c, $\cos(\theta_{\pi^+}) > 0.3$ and $\cos(\theta_\mu) > 0.3$.

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Photoproduction of the $f_1(1285)$ Meson

The CLAS collaboration Dickson, R. ; Schumacher, R.A. ; Adhikari, K.P. ; et al.
Phys.Rev. C93 (2016) 065202, 2016.
Inspire Record 1452551 DOI 10.17182/hepdata.72793
1 data table

Differential cross section for $\gamma p \to f_1(1285) p \to \eta \pi^+ \pi^- p$ in nanobarns/steradian. The point-to-point uncertainties are given in separate statistical and systematic contributions.


Study of $\pi^0$ pair production in single-tag two-photon collisions

The Belle collaboration Masuda, M. ; Uehara, S. ; Watanabe, Y. ; et al.
Phys.Rev. D93 (2016) 032003, 2016.
Inspire Record 1390112 DOI 10.17182/hepdata.71443

We report a measurement of the differential cross section of π0 pair production in single-tag two-photon collisions, γ*γ→π0π0, in e+e- scattering. The cross section is measured for Q2 up to 30  GeV2, where Q2 is the negative of the invariant mass squared of the tagged photon, in the kinematic range 0.5  GeV<W<2.1  GeV and |cosθ*|<1.0 for the total energy and pion scattering angle, respectively, in the γ*γ center-of-mass system. The results are based on a data sample of 759  fb-1 collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. The transition form factor of the f0(980) and that of the f2(1270) with the helicity-0, -1, and -2 components separately are measured for the first time and are compared with theoretical calculations.

10 data tables

$W$ dependence of the differential cross section ${\rm d}\sigma/{\rm d}|\cos\theta^*|$ in five $|\cos\theta^*|$ bins for $Q^2$=3.45 GeV$^2$.

$W$ dependence of the differential cross section ${\rm d}\sigma/{\rm d}|\cos\theta^*|$ in five $|\cos\theta^*|$ bins for $Q^2$=4.46 GeV$^2$.

$W$ dependence of the differential cross section ${\rm d}\sigma/{\rm d}|\cos\theta^*|$ in five $|\cos\theta^*|$ bins for $Q^2$=5.47 GeV$^2$.

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Measurement of top quark polarisation in t-channel single top quark production

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
JHEP 1604 (2016) 073, 2016.
Inspire Record 1403169 DOI 10.17182/hepdata.38092
4 data tables

The normalized differential cross section as a function of unfolded $\cos\theta_{\mu}^{*}$ for top quark.

The normalized differential cross section as a function of unfolded $\cos\theta_{\mu}^{*}$ for top antiquark.

The normalized differential cross section as a function of unfolded $\cos\theta_{\mu}^{*}$ for top quark and antiquark.

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MEASUREMENT OF THE SPECTATOR PROTON YIELD AT 0 ANGLE IN THE DEUTERON STRIPPING REACTION ON CARBON AT 8.9-GeV/c. (IN RUSSIAN)

Ableev, V.g. ; Vorobev, G.g. ; Zaporozhets, S.a. ; et al.
Yad.Fiz. 37 (1983) 132-136, 1983.
Inspire Record 192436 DOI 10.17182/hepdata.38079

The invariant cross section of the reaction of deuteron stripping on carbon target has been measured at a deuteron momentum of 8.9 GeV/c. The cross section is obtained at a zero detection angle of the stripping proton: E/p2xd2σ/dpdΩ=(281+-9)xbxGeV/srx(GeV/c)3. This value is consistent with the one calculated in the framework of the Bertocci-Treleani model of deuteron fragmentation. When the method of Nissen-Meyer is used for orthogonalization of the wave functions of primary deuteron and the (np) system, resulting from its disintegration, a similar calculation gives the result, which is 1.4 times larger than the measured value. Distribution in the cosine of angle of proton yield at the fixed proton momentum p turned out to be near to isotropy one and distribution in p at the fixed cos theta has the maximum at p=50 MeV/c

3 data tables

Photoproduction of $\omega$ mesons off protons and neutrons

The CBELSA/TAPS collaboration Dietz, F. ; Metag, V. ; Anisovich, A.V. ; et al.
Eur.Phys.J. A51 (2015) 6, 2015.
Inspire Record 1340913 DOI 10.17182/hepdata.69767

ω photoproduction off hydrogen and deuterium has been studied with the tagged photon beam of the ELSA accelerator in Bonn for photon energies up to 2.0 GeV. The ω meson has been identified via the ω → π$^{0}$ γ → γγγ decay mode, using the combined setup of the Crystal Barrel/TAPS detector systems. Both inclusive and exclusive analyses have been carried out. Differential and total cross-sections have been derived for ω mesons produced off free protons and off protons and neutrons bound in deuterium. The cross-section for the production off the bound neutron is found to be a factor of ≈ 1.3 larger than the one off the bound proton in the incident beam energy region 1.2 GeV < E$_{γ}$ < 1.6 GeV. For higher incident beam energies this factor goes down to ≈ 1.1 at 2.0 GeV. The cross-sections of this work have been used as normalization for transparency ratio measurements.

85 data tables

Differential cross-sections of $\omega$ mesons produced off the free proton versus $\cos(\theta^\omega_{\mathrm{c.m.}})$ and versus the momentum transfer to the nucleon, $t$, for incident photon energy $E_\gamma$ = 1.125-1.150 GeV.

Differential cross-sections of $\omega$ mesons produced off the free proton versus $\cos(\theta^\omega_{\mathrm{c.m.}})$ and versus the momentum transfer to the nucleon, $t$, for incident photon energy $E_\gamma$ = 1.150-1.175 GeV.

Differential cross-sections of $\omega$ mesons produced off the free proton versus $\cos(\theta^\omega_{\mathrm{c.m.}})$ and versus the momentum transfer to the nucleon, $t$, for incident photon energy $E_\gamma$ = 1.175-1.200 GeV.

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Cross sections for interaction of $K^{\pm}$ mesons with nuclei of C, Al, Ti, and Cd in the region of 1.5 GeV/c

Afonasiev, V.N. ; Borisov, V.S. ; Borodina, I.N. ; et al.
Sov.J.Nucl.Phys. 47 (1988) 1049-1053, 1988.
Inspire Record 1392556 DOI 10.17182/hepdata.9
6 data tables

No description provided.

No description provided.

THESE ARE CORRECTED DATA FROM YF 40, 34. PROPER TABLES IN YF 40, 34 MUST. BE REPLACED BY THE GOOD ONES.

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$\pi^{-}$C collisions with backward proton emission at 4 and 40 GeV/c

Angelov, N. ; Lutpullaev, S.L. ; Nikitina, V.F. ; et al.
Sov.J.Nucl.Phys. 33 (1981) 98-99, 1981.
Inspire Record 1392857 DOI 10.17182/hepdata.17814
13 data tables

PROTONS MOMENTA LIE IN LAB BACKWARD HEMISPHERE.

No description provided.

No description provided.

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MEASUREMENT OF THE REAL TO IMAGINARY RATIO OF THE ANTI-P P FORWARD SCATTERING AMPLITUDES

Ashford, V. ; Sainio, M.E. ; Sakitt, M. ; et al.
Phys.Rev.Lett. 54 (1985) 518-521, 1985.
Inspire Record 216074 DOI 10.17182/hepdata.20329
3 data tables

RESULTS OF FITS TO THE FORWARD-SCATTERING DIFFERENTIAL CROSS SECTIONS ASSUMING THE RATIO OF THE SPIN-FLIP TO NON-SPIN-FLIP PARTS OF THE FORWARD AMPLITUDE IS ZERO.

RESULTS OF FITS TO THE FORWARD-SCATTERING DIFFERENTIAL CROSS SECTIONS ASSUMING THE RATIO OF THE SPIN-FLIP TO NON-SPIN-FLIP PARTS OF THE FORWARD AMPLITUDE IS PARAMATERISED AS 0.3698-0.1384*PLAB(IN GEV).


Measurement of the gamma gamma ---> pi+ pi- and gamma gamma ---> K+ K- processes at energies of 2.4-Gev to 4.1-GeV

The Belle collaboration Nakazawa, H. ; Uehara, S. ; Abe, K. ; et al.
Phys.Lett. B615 (2005) 39-49, 2005.
Inspire Record 667712 DOI 10.17182/hepdata.68395

We have measured pi+pi- and K+K- production in two-photon collisions using 87.7 /fb of data collected with the Belle detector at the asymmetric energy e+e- collider KEKB. The cross sections are measured to high precision in the two-photon center-of-mass energy (W) range between 2.4 GeV < W < 4.1 GeV and angular region |cos theta^{*}| < 0.6. The cross section ratio sigma(gammagamma->K+K-)/sigma(gammagamma->pi+pi-) is measured to be 0.89 +- 0.04(stat) +- 0.15(syst) in the range of 3.0 GeV < W < 4.1 GeV, where the ratio is energy independent. We observe a sin^{-4} theta^{*} behavior of the cross section in the same W range. Production of chi_{c0} and chi_{c2} mesons is observed in both gammagamma -> pi+pi- and gammagamma -> K+K- modes.

6 data tables

Cross sections for PI+ PI- and K+ K- production.

Ratio of K+ K- to PI+ PI- production in the region of W from 3.0 to 4.1 GeV, where the ratio is energy independent.

Angular dependence of the normalized differential cross section, $\sigma_0^{-1}{\rm d}\sigma/{\rm d}|\cos\theta^*|$, for the $\pi^+\pi^-$ process. The errors are statistical only.

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Pion - proton elastic scattering at large angles from 0.9-GeV/c to 2-GeV/c

Abramov, B.M. ; Bulychjov, Sergey A. ; Dukhovskoi, I.A. ; et al.
Sov.J.Nucl.Phys. 54 (1991) 332-337, 1991.
Inspire Record 318074 DOI 10.17182/hepdata.39980
11 data tables

THE MOMENTUM OF EACH INCIDENT PION WAS DETERMINED WITH AN ACCURACY 0.2 PCT.

THE MOMENTUM OF EACH INCIDENT PION WAS DETERMINED WITH AN ACCURACY 0.2 PCT.

THE MOMENTUM OF EACH INCIDENT PION WAS DETERMINED WITH AN ACCURACY 0.2 PCT.

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Exclusive Measurements of pp ---> dpi+ pi0: Double-Pionic Fusion without ABC Effect

The CELSIUS/WASA collaboration Kren, F. ; Bashkanov, M. ; Bogoslawsky, D. ; et al.
Phys.Lett. B684 (2010) 110-113, 2010.
Inspire Record 833116 DOI 10.17182/hepdata.54563

Exclusive measurements of the reaction pp -> dpi+pi0 have been carried out at T_p = 1.1 GeV at the CELSIUS storage ring using the WASA detector. The isovector pi+pi0 channel exhibits no enhancement at low invariant pipi masses, i. e. no ABC effect. The differential distributions are in agreement with the conventional t-channel Delta-Delta excitation process, which also accounts for the observed energy dependence of the total cross section. This is an update of a previously published version -- see important note at the end of the article.

3 data tables

Updated total cross section for the reaction P P --> DEUT PI+ PI0, from the erratum.

Angular distribution of the PI0 in the CM system for the process P P --> DEUT PI+ PI0. As described in the erratum, these values should be multiplied by a factor of 2.3.

Angular distribution of the deuterium in the CM system for the process P P --> DEUT PI+ PI0. As described in the erratum, these values should be multiplied by a factor of 2.3.


Differential cross section of gamma n to K+ Sigma- on bound neutrons with incident photons from 1.1 to 3.6 GeV

The CLAS collaboration Pereira, S.Anefalos ; Mirazita, M. ; Rossi, P. ; et al.
Phys.Lett. B688 (2010) 289-293, 2010.
Inspire Record 841145 DOI 10.17182/hepdata.38239

Differential cross sections of the reaction gamma d to K+ Sigma- (p) have been measured with the CLAS detector at Jefferson Lab using incident photons with energies between 1.1 and 3.6 GeV. This is the first complete set of strangeness photoproduction data on the neutron covering a broad angular range. At energies close to threshold and up to E_gamma ~ 1.8 GeV, the shape of the angular distribution is suggestive of the presence of s-channel production mechanisms. For E_gamma > 1.8 GeV, a clear forward peak appears and becomes more prominent as the photon energy increases, suggesting contributions from t-channel production mechanisms. These data can be used to constrain future analysis of this reaction.

25 data tables

Differential cross section for the reaction GAMMA DEUT --> K+ SIGMA-(P) at incident photon energy 1.15 GeV.. Errors contain both statistics and systematics.

Differential cross section for the reaction GAMMA DEUT --> K+ SIGMA-(P) at incident photon energy 1.25 GeV.. Errors contain both statistics and systematics.

Differential cross section for the reaction GAMMA DEUT --> K+ SIGMA-(P) at incident photon energy 1.35 GeV.. Errors contain both statistics and systematics.

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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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Photoproduction of eta-mesons off nuclei for E(gamma) < 2.2-GeV

The CBELSA TAPS collaborations Mertens, T. ; Jaegle, I. ; Muhlich, P. ; et al.
Eur.Phys.J. A38 (2008) 195-207, 2008.
Inspire Record 799499 DOI 10.17182/hepdata.50323

Photoproduction of $\eta$ mesons off $^{12}$C, $^{40}$Ca, $^{93}$Nb, and $^{nat}$Pb nuclei has been measured with a tagged photon beam with energies between 0.6 and 2.2 GeV. The experiment was performed at the Bonn ELSA accelerator with the combined setup of the Crystal Barrel and TAPS calorimeters. It aimed at the in-medium properties of the S$_{11}$(1535) nucleon resonance and the study of the absorption properties of nuclear matter for $\eta$ mesons. Careful consideration was given to contributions from $\eta\pi$ final states and secondary production mechanisms of $\eta$-mesons e.g. from inelastic $\pi N$ reactions of intermediate pions. The analysis of the mass number scaling shows that the nuclear absorption cross section $\sigma_{N\eta}$ for $\eta$ mesons is constant over a wide range of the $\eta$ momentum. The comparison of the excitation functions to data off the deuteron and to calculations in the framework of a BUU-model show no unexplained in-medium modifications of the S$_{11}$(1535).

10 data tables

Inclusive energy distribution for incident photon energy 0.650 to 0.835 GeV.

Inclusive energy distribution for incident photon energy 0.835 to 1.050 GeV.

Inclusive energy distribution for incident photon energy 1.050 to 1.550 GeV.

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High-statistics measurement of neutral pion-pair production in two-photon collisions

The Belle collaboration Uehara, S. ; Watanabe, Y. ; Adachi, I. ; et al.
Phys.Rev. D78 (2008) 052004, 2008.
Inspire Record 786406 DOI 10.17182/hepdata.50151

We report a high-statistics measurement of differential cross sections for the process gamma gamma -> pi^0 pi^0 in the kinematic range 0.6 GeV <= W <= 4.0 GeV and |cos theta*| <= 0.8, where W and theta* are the energy and pion scattering angle, respectively, in the gamma gamma center-of-mass system. Differential cross sections are fitted to obtain information on S, D_0, D_2, G_0 and G_2 waves. The G waves are important above W ~= 1.6 GeV. For W <= 1.6 GeV the D_2 wave is dominated by the f_2(1270) resonance while the S wave requires at least one additional resonance besides the f_0(980), which may be the f_0(1370) or f_0(1500). The differential cross sections are fitted with a simple parameterization to determine the parameters (the mass, total width and Gamma_{gamma gamma}B(f_0 -> pi^0 pi^0)) of this scalar meson as well as the f_0(980). The helicity 0 fraction of the f_2(1270) meson, taking into account interference for the first time, is also obtained.

29 data tables

Differential cross section for W = 0.61, 0.63 and 0.65 GeV.

Differential cross section for W = 0.67, 0.69 and 0.71 GeV.

Differential cross section for W = 0.73, 0.75 and 0.77 GeV.

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Photoproduction of Lambda(1405) and Sigma0(1385) on the proton at E(gamma) = 1.5-2.4-GeV

Niiyama, M. ; Fujimura, H. ; Ahn, D.S. ; et al.
Phys.Rev. C78 (2008) 035202, 2008.
Inspire Record 786670 DOI 10.17182/hepdata.50883

Differential cross sections for $\gamma p \to K^+\Lambda(1405)$ and $\gamma p \to K^+\Sigma^0(1385)$ reactions have been measured in the photon energy range from 1.5 to 2.4 GeV and the angular range of $0.8<\cos(\Theta)<1.0$ for the $K^+$ scattering angle in the center-of-mass system. This data is the first measurement of the $\Lambda(1405)$ photoproduction cross section. The lineshapes of \LamS measured in $\Sigma^+\pi^-$ and $\Sigma^-\pi^+$ decay modes were different with each other, indicating a strong interference of the isospin 0 and 1 terms of the $\Sigma\pi$ scattering amplitudes. The ratios of \LamS production to \SigS production were measured in two photon energy ranges: near the production threshold ($1.5<E_\gamma<2.0$ GeV) and far from it ($2.0 <E_\gamma<2.4$ GeV). The observed ratio decreased in the higher photon energy region, which may suggest different production mechanisms and internal structures for these hyperon resonances.

2 data tables

Cross section for LAMBDA(1405) production.

Cross section for SIGMA(1385)0 production.


Measurement of the e+ e- ---> W+ W- cross section and W decay branching fractions at LEP

The OPAL collaboration
Eur.Phys.J. C52 (2007) 767-785, 2007.
Inspire Record 757918 DOI 10.17182/hepdata.48533

From a total data sample of 701.1 pb^-1 recorded with e+e- centre-of-mass energies of sqrt = 161-209 GeV with the OPAL detector at LEP, 11693 W-pair candidate events are selected. These data are used to obtain measurements of the W-pair production cross sections at 10 different centre-of-mass energies. The ratio of the measured cross sections to the Standard Model expectation is found to be: data/SM = 1.002 +- 0.011(stat.) +- 0.007(syst.) +- 0.005(theory), where the uncertainties are statistical, experimental systematics and theory systematics respectively. The data are used to determine the W boson branching fractions, which are found to be consistent with lepton universality of the charged current interaction. Assuming lepton universality, the branching ratio to hadrons is determined to be 67.41 +- 0.37(stat.) +- 0.23(syst.)%, from which the CKM matrix element Vcs is determined to be 0.96+-0.017(stat.)+-0.012(syst.). The differential cross section as a function of the W^- production angle is measured for the qqev and qqmv final states. The results described in this paper are consistent with the expectations from the Standard Model.

5 data tables

Measured cross section for the (lepton nu lepton nu) decay mode.

Measured cross section for the (quark quark lepton nu) decay mode.

Measured cross section for the (quark quark quark quark) decay mode.

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K0 pi0 Sigma+ and K*0 Sigma+ photoproduction off the proton

The CBELSA/TAPS collaboration Nanova, M. ; Bacelar, J.C.S. ; Bantes, B. ; et al.
Eur.Phys.J. A35 (2008) 333-342, 2008.
Inspire Record 781382 DOI 10.17182/hepdata.51372

The exclusive reactions $\gamma p \to K^{*0} \Sigma^+(1189)$ and $\gamma p \to K^{0} \pi^{0}\Sigma^+(1189)$, leading to the p 4$\pi^{0}$ final state, have been measured with a tagged photon beam for incident energies from threshold up to 2.5 GeV. The experiment has been performed at the tagged photon facility of the ELSA accelerator (Bonn). The Crystal Barrel and TAPS detectors were combined to a photon detector system of almost 4$\pi$ geometrical acceptance. Differential and total cross sections are reported. At energies close to the threshold, a flat angular distribution has been observed for the reaction $\gamma p\to K^{0} \pi^{0}\Sigma^+$ suggesting dominant s-channel production. $\Sigma^*(1385)$ and higher lying hyperon states have been observed. An enhancement in the forward direction in the angular distributions of the reaction $\gamma p \to K^{*0}\Sigma^+$ indicates a $t$-channel exchange contribution to the reaction mechanism. The experimental data are in reasonable agreement with recent theoretical predictions.

13 data tables

Differential cross section D(SIG)/DCOS(THETA(SIG+)) for the GAMMA P --> K0 PI0 SIGMA+ reaction for beam energies 1500-1700 and 1700-1850 MeV.

Differential cross section D(SIG)/DCOS(THETA(SIG+)) for the GAMMA P --> K0 PI0 SIGMA+ reaction for beam energies 1850-2000 and 2000-2150 MeV.

Differential cross section D(SIG)/DCOS(THETA(SIG+)) for the GAMMA P --> K0 PI0 SIGMA+ reaction for beam energies 2150-2300 and 2300-2500 MeV.

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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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Multijets in photoproduction at HERA

The ZEUS collaboration Gwenlan, C. ;
Acta Phys.Polon. B33 (2002) 3123-3128, 2002.
Inspire Record 602140 DOI 10.17182/hepdata.51400
7 data tables

The measured normalised costheta3 distributions.

The measured normalised psi3 distributions.

The measured normalised X3 distributions.

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A Study of gamma gamma ---> K0(S) K0(S) production at energies of 2.4-GeV to 4.0-GeV at Belle

The Belle collaboration Chen, W.T. ; Abe, K. ; Adachi, I. ; et al.
Phys.Lett. B651 (2007) 15-21, 2007.
Inspire Record 726900 DOI 10.17182/hepdata.38419

$K^0_SK^0_S$ production in two-photon collisions has been studied using a 397.6 fb$^{-1}$ data sample collected with the Belle detector at the KEKB $e^+e^-$ collider. For the first time the cross sections are measured in the two-photon center-of-mass energy range between 2.4 GeV and 4.0 GeV and angular range $|\cos\theta^*|<0.6$. Combining the results with measurements of $\gamma\gamma\to K^+K^-$ from Belle, we observe that the cross section ratio $\sigma(K^0_SK^0_S)/\sigma(K^+K^-)$ decreases from ~0.13 to ~0.01 with increasing energy. Signals for the $\chi_{c0}$ and $\chi_{c2}$ charmonium states are also observed.

7 data tables

Total cross section for the process GAMMA GAMMA --> K0S K0S.

Angular distribution of the cross section in the W range 2.4 to 2.5 GeV.

Angular distribution of the cross section in the W range 2.5 to 2.6 GeV.

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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.

141 data tables

Total cross section.

No description provided.

No description provided.