Read, A.L.
Polarization
Max results
Sort by Reverse order

Showing 10 of 60 results

Study on the cross section asymmetry of deuteron photodisintegration induced by low energy polarized γ quanta

Barannik, V.P. ; Gorbenko, V.G. ; Gushchin, V.A. ; et al.
Yad.Fiz. 38 (1983) 1108-1100, 1983.
Inspire Record 1408810 DOI 10.17182/hepdata.17732

Results are presented on measured asymmetry parameter in the cross sections of the deuteron photodesintegration by linearly polarized photon beam in the energy range 40-70 MeV for the proton emission angles of 75 and 90 deg in the c. m. s. The experimental data are compared with the theoretical calculations by Partovi, Arenhovel, as well as with calculations performed within an invariant approach with gauge-invariant amplitudes in the pole approximation. The results of the calculation by Arenhovel and the present calculations satisfactorily agree with the experimental data, while the Partovi theory does not describe the asymmetry parameter measurements for photon energies above 40 MeV

1 data table
Table 1

No description provided.


Angular dependence of the asymmetry of the cross section for the reaction $\gamma$p $\rightarrow$ $\Delta^{++}\pi^{-}$ at a photon energy 650 MeV

Ganenko, V.B. ; Gorbenko, V.B. ; Zhebrovskii, Yu.V. ; et al.
JETP Lett. 16 (1972) 310-312, 1972.
Inspire Record 1393130 DOI 10.17182/hepdata.39786

None

1 data table
Table 1

No description provided.


Angular dependence of the asymmetry of the cross sections for the reactions $^{4}$He($\gamma , p$)T and $^{4}$He($\gamma , n$)$^{3}$He induced by 40-, 60-, and 80-MeV linearly polarized photons

Lyakhno, Yu.P. ; Voloshuchuk, V.I. ; Ganenko, V.B. ; et al.
Phys.Atom.Nucl. 59 (1996) 14-18, 1996.
Inspire Record 1392928 DOI 10.17182/hepdata.17187

None

1 data table
Table 1

THE ASYMMETRY SIGMA HAS BEEN DETERMINED BY THE FORMULA: D(SIG)/D(OMEGA)=D(SIG0)/D(OMEGA)*(1+P*SIGMA*COS(PHI)), WHERE D(SIG0)/D(OMEGA) - CROSS SECTION ON U NPOLARIZED PHOTON BEAM, P - BEAM POLARIZATION, PHI - ASIMUTHAL ANGLE BETWEEN POLARIZATION VECTOR OF BEAM AND THE PLANE OF THE REACTION.


Cross-section asymmetry in two-particle photodisintegration of helium-3 by linearly polarized protons

Belyaev, A.A. ; Ganenko, V.B. ; Get'man, V.A. ; et al.
Sov.J.Nucl.Phys. 44 (1986) 181-183, 1986.
Inspire Record 1392511 DOI 10.17182/hepdata.17441

None

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Measurement of the transverse polarization of $\Lambda$ and $\bar{\Lambda}$ hyperons produced in proton-proton collisions at $\sqrt{s}=7$ TeV using the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev.D 91 (2015) 032004, 2015.
Inspire Record 1332748 DOI 10.17182/hepdata.66547

The transverse polarization of $\Lambda$ and $\bar\Lambda$ hyperons produced in proton-proton collisions at a center-of-mass energy of 7 TeV is measured. The analysis uses 760 $\mu$b$^{-1}$ of minimum bias data collected by the ATLAS detector at the LHC in the year 2010. The measured transverse polarization averaged over Feynman $x_{\rm F}$ from $5\times 10^{-5}$ to 0.01 and transverse momentum $p_{\rm T}$ from 0.8 to 15 GeV is $-0.010 \pm 0.005({\rm stat}) \pm 0.004({\rm syst})$ for $\Lambda$ and $0.002 \pm 0.006({\rm stat}) \pm 0.004({\rm syst})$ for $\bar\Lambda$. It is also measured as a function of $x_{\rm F}$ and $p_{\rm T}$, but no significant dependence on these variables is observed. Prior to this measurement, the polarization was measured at fixed-target experiments with center-of-mass energies up to about 40 GeV. The ATLAS results are compatible with the extrapolation of a fit from previous measurements to the $x_{\rm F}$ range covered by this mesurement.

5 data tables
Table 1

Transverse polarization POL of LAMBDA and LAMBDABAR hyperons averaged over PT and XF.

Table 2

Transverse polarization POL of LAMBDA and LAMBDABAR hyperons as a function of XF.

Table 3

Transverse polarization POL of LAMBDA and LAMBDABAR hyperons as a function of PT.

More…

Inclusive double-helicity asymmetries in neutral pion and eta meson production in $\vec{p}+\vec{p}$ collisions at $\sqrt{s}=200$ GeV

The PHENIX collaboration Adare, A. ; Aidala, C. ; Ajitanand, N.N. ; et al.
Phys.Rev.D 90 (2014) 012007, 2014.
Inspire Record 1282448 DOI 10.17182/hepdata.64716

Results are presented from data recorded in 2009 by the PHENIX experiment at the Relativistic Heavy Ion Collider for the double-longitudinal spin asymmetry, $A_{LL}$, for $\pi^0$ and $\eta$ production in $\sqrt{s} = 200$ GeV polarized $p$$+$$p$ collisions. Comparison of the $\pi^0$ results with different theory expectations based on fits of other published data showed a preference for small positive values of gluon polarization, $\Delta G$, in the proton in the probed Bjorken $x$ range. The effect of adding the new 2009 \pz data to a recent global analysis of polarized scattering data is also shown, resulting in a best fit value $\Delta G^{[0.05,0.2]}_{\mbox{DSSV}} = 0.06^{+0.11}_{-0.15}$ in the range $0.05<x<0.2$, with the uncertainty at $\Delta \chi^2 = 9$ when considering only statistical experimental uncertainties. Shifting the PHENIX data points by their systematic uncertainty leads to a variation of the best-fit value of $\Delta G^{[0.05,0.2]}_{\mbox{DSSV}}$ between $0.02$ and $0.12$, demonstrating the need for full treatment of the experimental systematic uncertainties in future global analyses.

9 data tables
Table 1

PI0 ASYM(LL) measurements from 2005.

Table 2

PI0 ASYM(LL) measurements from 2006.

Table 3

PI0 ASYM(LL) measurements from 2009.

More…

Polarization of J / psi and psi(2S) mesons produced in p anti-p collisions at s**(1/2) = 1.96-TeV

The CDF collaboration Abulencia, A. ; Adelman, Jahred A. ; Affolder, T. ; et al.
Phys.Rev.Lett. 99 (2007) 132001, 2007.
Inspire Record 747876 DOI 10.17182/hepdata.42742

We have measured the polarizations of J/ψ and ψ(2S) mesons as functions of their transverse momentum pT when they are produced promptly in the rapidity range |y|<0.6 with pT≥5  GeV/c. The analysis is performed using a data sample with an integrated luminosity of about 800  pb−1 collected by the CDF II detector. For both vector mesons, we find that the polarizations become increasingly longitudinal as pT increases from 5 to 30  GeV/c. These results are compared to the predictions of nonrelativistic quantum chromodynamics and other contemporary models. The effective polarizations of J/ψ and ψ(2S) mesons from B-hadron decays are also reported.

2 data tables
Table 1

Polarization parameter ALPHA for J/PSI production.

Table 2

Polarization parameter ALPHA for PSI(2S) production.


Measurement of the n p total cross section difference Delta(sigma(L))(np) at 1.39-GeV, 1.69-GeV, 1.89-GeV and 1.99-GeV

Sharov, V.I. ; Anischenko, N.G. ; Antonenko, V.G. ; et al.
Eur.Phys.J.C 37 (2004) 79-90, 2004.
Inspire Record 662636 DOI 10.17182/hepdata.43115

New accurate results of the neutron-proton spin-dependent total cross section difference $\Delta\sigma_{\mathrm L}(np)$

2 data tables
Table 1

Unpolarized total cross sections.

Table 2

Final results for SIG(NAME=CLL).


rivet Analysis
A precise measurement of the tau polarisation at LEP-1.

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.
Eur.Phys.J.C 14 (2000) 585-611, 2000.
Inspire Record 511443 DOI 10.17182/hepdata.49001

The$\tau$polarisation has been studied with the${\rm e^+e^-}\to \tau^+\tau^-$data collected by the DELPHI detector at LEP in

2 data tables
Table 1

The errors are statistical and systematic combined in quadrature.

Table 2

No description provided.


Measurements of the total cross section difference Delta(sigma(L)(n p)) at 1.59-GeV, 1.79-GeV and 2.20-GeV.

Sharov, V.I. ; Zaporozhets, S.A. ; Adiasevich, B.P. ; et al.
JINR Rapid Commun. 96 (1999) 5-23, 1999.
Inspire Record 513865 DOI 10.17182/hepdata.43287

New results of the neutron-proton spin-dependent total cross section difference$\Delta\sigma_L(np)$at the neutron beam kinetic energies 1.59, 1.79 and 2.20 GeV ar

2 data tables
Table 1

Final results from the np data.

Table 2

Values of the cross section difference at I=0 deduced by combining these npdata with pure pp (I=1) data from other experiments.