Helicity-dependent cross sections and double-polarization observable E in eta photoproduction from quasi-free protons and neutrons

The A2 collaboration Witthauer, L. ; Dieterle, M. ; Abt, S. ; et al.
Phys.Rev.C 95 (2017) 055201, 2017.
Inspire Record 1589331 DOI 10.17182/hepdata.132013

Precise helicity-dependent cross sections and the double-polarization observable $E$ were measured for $\eta$ photoproduction from quasi-free protons and neutrons bound in the deuteron. The $\eta\rightarrow 2\gamma$ and $\eta\rightarrow 3\pi^0\rightarrow 6\gamma$ decay modes were used to optimize the statistical quality of the data and to estimate systematic uncertainties. The measurement used the A2 detector setup at the tagged photon beam of the electron accelerator MAMI in Mainz. A longitudinally polarized deuterated butanol target was used in combination with a circularly polarized photon beam from bremsstrahlung of a longitudinally polarized electron beam. The reaction products were detected with the electromagnetic calorimeters Crystal Ball and TAPS, which covered 98\% of the full solid angle. The results show that the narrow structure observed earlier in the unpolarized excitation function of $\eta$ photoproduction off the neutron appears only in reactions with antiparallel photon and nucleon spin ($\sigma_{1/2}$). It is absent for reactions with parallel spin orientation ($\sigma_{3/2}$) and thus very probably related to partial waves with total spin 1/2. The behavior of the angular distributions of the helicity-dependent cross sections was analyzed by fitting them with Legendre polynomials. The results are in good agreement with a model from the Bonn-Gatchina group, which uses an interference of $P_{11}$ and $S_{11}$ partial waves to explain the narrow structure.

81 data tables

Diff. cross section for helicity-1/2 at W= 1.505 GeV

Diff. cross section for helicity-1/2 at W= 1.515 GeV

Diff. cross section for helicity-1/2 at W= 1.525 GeV

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Search for heavy resonances decaying to Z($\nu\bar{\nu}$)V(q$\bar{q}$') in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Andrejkovic, Janik Walter ; et al.
Phys.Rev.D 106 (2022) 012004, 2022.
Inspire Record 1923626 DOI 10.17182/hepdata.103856

A search is presented for heavy bosons decaying to Z($\nu\bar{\nu}$)V(qq'), where V can be a W or a Z boson. A sample of proton-proton collision data at $\sqrt{s} =$ 13 TeV was collected by the CMS experiment during 2016-2018. The data correspond to an integrated luminosity of 137 fb$^{-1}$. The event categorization is based on the presence of high-momentum jets in the forward region to identify production through weak vector boson fusion. Additional categorization uses jet substructure techniques and the presence of large missing transverse momentum to identify W and Z bosons decaying to quarks and neutrinos, respectively. The dominant standard model backgrounds are estimated using data taken from control regions. The results are interpreted in terms of radion, W' boson, and graviton models, under the assumption that these bosons are produced via gluon-gluon fusion, Drell-Yan, or weak vector boson fusion processes. No evidence is found for physics beyond the standard model. Upper limits are set at 95% confidence level on various types of hypothetical new bosons. Observed (expected) exclusion limits on the masses of these bosons range from 1.2 to 4.0 (1.1 to 3.7) TeV.

21 data tables

Simulated distributions are shown for the cosine of the decay angle of SM vector bosons in the rest frame of a parent particle with a mass (mX) of 2\TeV. Solid lines represent VBF scenarios. Dashed lines represent ggF/DY scenarios.

Distributions of mT for ggF/DY-produced resonances X of mass 4.5 TeV.

Distributions of mT for VBF-produced resonances X of mass 4.5 TeV.

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Measurement of the Longitudinal Spin Transfer to Lambda and Anti-Lambda Hyperons in Polarised Muon DIS

The COMPASS collaboration Alekseev, M. ; Alexakhin, V.Yu. ; Alexandrov, Yu. ; et al.
Eur.Phys.J.C 64 (2009) 171-179, 2009.
Inspire Record 824774 DOI 10.17182/hepdata.52400

The longitudinal polarisation transfer from muons to lambda and anti-lambda hyperons, D_LL, has been studied in deep inelastic scattering off an unpolarised isoscalar target at the COMPASS experiment at CERN. The spin transfers to lambda and anti-lambda produced in the current fragmentation region exhibit different behaviours as a function of x and xF . The measured x and xF dependences of D^lambda_LL are compatible with zero, while D^anti-lambda_LL tends to increase with xF, reaching values of 0.4 - 0.5. The resulting average values are D^lambda_LL = -0.012 +- 0.047 +- 0.024 and D^anti-lambda_LL = 0.249 +- 0.056 +- 0.049. These results are discussed in the frame of recent model calculations.

5 data tables

The weighted average of the spin transfers for the 2003 and 2004 data.

The XL dependence of the spin transfer from muons to the LAMBDA hyperon.

The X dependence of the spin transfer from muons to the LAMBDA hyperon.

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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.C 75 (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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Angular dependence of the pp elastic scattering spin correlation parameter Ann-00 between 0.8 and 2.8 GeV. II. Results for higher energies

Allgower, C.E. ; Ball, J. ; Beddo, M.E. ; et al.
Phys.Rev.C 64 (2001) 034003, 2001.
Inspire Record 561777 DOI 10.17182/hepdata.25291

Measurements at 18 beam kinetic energies between 1975 and 2795 MeV and at 795 MeV are reported for the pp elastic scattering spin correlation parameter A00nn=(N,N;0,0)=CNN=ANN. The c.m. angular range is typically 60°-100°. These results are compared to previous data from Saturne II and other accelerators. A search for energy-dependent structure at fixed c.m. angles is performed. Comparisons are made to phase shift analysis and theoretical model predictions of this spin observable.

20 data tables

Measured values of CNN at EKIN 795 Mev.. Fractional systematic uncertainty in the absolute beam and target polarization is +-0.032.

Measured values of CNN at EKIN 1975 Mev.. Fractional systematic uncertainty in the absolute beam and target polarization is +-0.052.

Measured values of CNN at EKIN 2035 Mev (from run period III).. Fractional systematic uncertainty in the absolute beam and target polarization is +-0.051.

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Angular dependence of the p p elastic scattering spin correlation parameter A(00nn) between 0.8 and 2.8 GeV: Results for 1.80-GeV to 2.24-GeV

Allgower, C.E. ; Ball, J. ; Barabash, L.S. ; et al.
Phys.Rev.C 62 (2000) 064001, 2000.
Inspire Record 539075 DOI 10.17182/hepdata.25464

Measurements at 19 beam kinetic energies between 1795 and 2235 MeV are reported for the pp elastic scattering spin correlation parameter A00nn=ANN=CNN. The c.m. angular range is typically 60–100°. The measurements were performed at Saturne II with a vertically polarized beam and target (transverse to the beam direction and scattering plane), a magnetic spectrometer and a recoil detector, both instrumented with multiwire proportional chambers, and beam polarimeters. These results are compared to previous data from Saturne II and elsewhere.

21 data tables

Measured values of CNN at EKIN 1795 Mev.. Fractional systematic uncertainty in the absolute beam and target polarization is +-0.110.

Measured values of CNN at EKIN 1845 Mev.. Fractional systematic uncertainty in the absolute beam and target polarization is +-0.073.

Measured values of CNN at EKIN 1935 Mev.. Fractional systematic uncertainty in the absolute beam and target polarization is +-0.095.

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Quasi-elastic p n scattering in Li-6_D and Li-6_H targets from 1.1-GeV to 2.4-GeV.

de Lesquen, A. ; Allgower, C.E. ; Ball, J. ; et al.
Eur.Phys.J.C 11 (1999) 69-78, 1999.
Inspire Record 505046 DOI 10.17182/hepdata.43332

A polarized proton beam from SATURNE II, the Saclay polarized targets with$^6$Li compounds, and an unpol

17 data tables

The PN analysing power of polarized protons scattered on the polarized and/or unpolarized LiD and LiH targets.

The PN analysing power of polarized protons scattered on the polarized and/or unpolarized LiD and LiH targets.

The PN analysing power of polarized protons scattered on the polarized and/or unpolarized LiD and LiH targets.

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Elastic and quasi-elastic p p scattering in Li-6_H and Li-6_D targets between 1.1-GeV and 2.4-GeV.

Ball, J. ; Allgower, C.E. ; Beddo, M. ; et al.
Eur.Phys.J.C 11 (1999) 51-67, 1999.
Inspire Record 505045 DOI 10.17182/hepdata.43403

A polarized proton beam extracted from SATURNE II, the Saclay polarized target with$^6$Li compounds, and

25 data tables

Analysing power measurements in the scattering of polarized protons from either hydrogen in the LiH target or on bound protons in the LiD target. The three sets of results are independent.

Analysing power measurements in the scattering of polarized protons from either hydrogen in the LiH target or on bound protons in the LiD target. The three sets of results are independent.

Analysing power measurements in the scattering of polarized protons from either hydrogen in the LiH target or on bound protons in the LiD target. The three sets of results are independent.

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Zero-degree differential cross-sections and DNN values for the O-17, O-18 (,) F-17, F-18 reactions at E(p) = 118 MeV

van Heerden, I.J. ; Palarczyk, M. ; Wang, X. ; et al.
Phys.Rev.C 59 (1999) 1488-1496, 1999.
Inspire Record 516334 DOI 10.17182/hepdata.25605

We present zero-degree differential cross sections and transverse spin-transfer coefficients DNN(0°) for the 17,18O(p→,n→)17,18F reactions at Ep=118 MeV. For the transition to the 17F(g.s.) to which several multipoles contribute, the measured DNN(0°)=−0.13±0.05 is used to separate the Fermi and Gamow-Teller contributions at 0°. The empirical Gamow-Teller strengths and the Fermi strengths are employed to estimate the solar neutrino absorption cross section in 17O and 18O.

2 data tables

No description provided.

No description provided.


p p elastic scattering polarization transfer K(onno) and depolarization D(onon) between 1.94-GeV and 2.80-GeV.

Allgower, C.E. ; Ball, J. ; Barabash, L.S. ; et al.
Eur.Phys.J.C 5 (1998) 453-460, 1998.
Inspire Record 481194 DOI 10.17182/hepdata.43094

A polarized proton beam extracted from SATURNE II and the Saclay polarized proton target were used to measure the rescattering observables$K_{onno}$and

27 data tables

No description provided.

No description provided.

No description provided.

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