Search results for "scattering [electron hadron]"
showing 10 items of 654 documents
Electron resonance scattering from mercury
1977
The differential cross section and the spin polarisation of electrons scattered elastically from mercury have been measured as a function of collision energy in the range 4.0 to 6.0 eV for several selected scattering angles. The observed data can be understood if one assumes that resonances are formed at 4.55 eV in the 2S1/2, at 4.71 eV in the 2D3/2 and at 4.94 eV and 5.51 eV respectively in the 2D5/2 scattering state.
Differential cross section for the reaction 2H(γ, p)n from 133 to 158 MeV
1991
The cross section for the reaction 2H(γ, p)n has been measured at laboratory photon energies Eγ = 133−158 MeV and c.m. angles between 30° and 150°. The reaction was induced by a tagged bremsstrahlung photon beam incident on a liquid deuterium target. The uncertainty in the absolute cross sections is ⩽ 5%. There is now reasonable agreement between recent measurements in this energy region and the overall data set now defines the cross section sufficiently well to provide a test of current models of the reaction.
Deuteron form factor measurements at low momentum transfers
2016
A precise measurement of the elastic electron-deuteron scattering cross section at four-momentum transfers of 0.24 fm−1 ≤ Q ≤ 2.7 fm−1 has been performed at the Mainz Microtron. In this paper we describe the utilized experimental setup and the necessary analysis procedure to precisely determine the deuteron charge form factor from these data. Finally, the deuteron charge radius rd can be extracted from an extrapolation of that form factor to Q 2 = 0.
Panel Discussion Spin and Polarization Effects in Atomic Processes
1973
In view of all the present activity on spin and polarization effects in atomic processes, perhaps the best approach to my introduction is first to summarize some of the most important recent results and to restrict myself to some typical characteristics.
XENON100 dark matter results from a combination of 477 live days
2016
We report on WIMP search results of the XENON100 experiment, combining three runs summing up to 477 live days from January 2010 to January 2014. Data from the first two runs were already published. A blind analysis was applied to the last run recorded between April 2013 and January 2014 prior to combining the results. The ultra-low electromagnetic background of the experiment, ~$5 \times 10^{-3}$ events/(keV$_{\mathrm{ee}}\times$kg$\times$day) before electronic recoil rejection, together with the increased exposure of 48 kg $\times$ yr improves the sensitivity. A profile likelihood analysis using an energy range of (6.6 - 43.3) keV$_{\mathrm{nr}}$ sets a limit on the elastic, spin-independe…
A novel kind of neutrino oscillation experiment
1994
A novel method to look for neutrino oscillations is proposed based on the elastic scattering process $\bar{\nu}_{i} e^{-}\rightarrow \bar{\nu}_{i} e^{-}$, taking advantage of the dynamical zero present in the differential cross section for $\bar{\nu}_{e} e^{-}\rightarrow \bar{\nu}_{e} e^{-}$. An effective tunable experiment between the "appearance" and "disappearance" limits is made possible. Prospects to exclude the allowed region for atmospheric neutrino oscillations are given.
Polarization of τ in quasielastic (anti)neutrino scattering: The role of spectral functions
2019
We present a study of the $\tau$ polarization in charged-current quasielastic (anti)neutrino-nucleus scattering. The spectral function formalism is used to compute the differential cross section and the polarization components for several kinematical setups, relevant for neutrino-oscillation experiments. The effects of the nuclear corrections in these observables are investigated by comparing the results obtained using two different realistic spectral functions, with those deduced from the relativistic global Fermi gas model, where only statistical correlations are accounted for. We show that the spectral functions, although they play an important role when predicting the differential cross…
The role of vector-baryon channels and resonances in the γp→K0Σ+ and γn→K0Σ0 reactions near the K⁎Λ threshold
2013
Abstract We have studied the γ p → K 0 Σ + reaction in the energy region around the K ⁎ Λ and K ⁎ Σ thresholds, where the CBELSA/TAPS cross section shows a sudden drop and the differential cross section experiences a transition from a forward-peaked distribution to a flat one. Our coupled-channel model incorporates the dynamics of the vector meson–baryon interaction which is obtained from the hidden gauge formalism. We find that the cross section in this energy region results from a delicate interference between amplitudes having K ⁎ Λ and K ⁎ Σ intermediate states. The sharp downfall is dictated by the presence of a nearby N ⁎ resonance produced by our model, a feature that we have employe…
Meson exchange currents in pion double charge exchange at high energies
1995
In this letter we study the high energy behavior of the forward differential cross section for the $^{18}O(\pi^+,\pi^-)^{18}Ne$ double charge exchange reaction. We have evaluated the sequential and the meson exchange current mechanisms. The meson exchange current contribution shows a very weak energy dependence and becomes relevant at incident pion kinetic energies above 600 MeV.
Measurement ofΥ(1S+2S+3S)production inp+pand Au + Au collisions atsNN=200GeV
2015
Measurements of bottomonium production in heavy-ion and p + p collisions at the Relativistic Heavy Ion Collider (RHIC) are presented. The inclusive yield of the three states, (1S + 2S + 3S), was measured in the PHENIX experiment via electron-positron decay pairs at midrapidity for Au + Au and p + p collisions at root sNN = 200 GeV. The (1S + 2S + 3S) -> e(+)e(-) differential cross section at midrapidity was found to be B(ee)d sigma/dy = 108 +/- 38 (stat) +/- 15 (syst) +/- 11 (luminosity) pb in p + p collisions. The nuclear modification factor in the 30% most central Au + Au collisions indicates a suppression of the total. state yield relative to the extrapolation from p + p collision data. …