32 research outputs found
Feasibility studies of time-like proton electromagnetic form factors at PANDA at FAIR
Simulation results for future measurements of electromagnetic proton form factors at PÂŻANDA (FAIR) within the PandaRoot software framework are reported. The statistical precision with which the proton form factors can be determined is estimated. The signal channel pÂŻpâe+eâpÂŻpâe+eâ is studied on the basis of two different but consistent procedures. The suppression of the main background channel, i.e. pÂŻpâÏ+ÏâpÂŻpâÏ+Ïâ , is studied. Furthermore, the background versus signal efficiency, statistical and systematical uncertainties on the extracted proton form factors are evaluated using two different procedures. The results are consistent with those of a previous simulation study using an older, simplified framework. However, a slightly better precision is achieved in the PandaRoot study in a large range of momentum transfer, assuming the nominal beam conditions and detector performance
Feasibility studies of the time-like proton electromagnetic form factor measurements with PANDA at FAIR
The possibility of measuring the proton electromagnetic form factors in the
time-like region at FAIR with the \PANDA detector is discussed. Detailed
simulations on signal efficiency for the annihilation of into a
lepton pair as well as for the most important background channels have been
performed. It is shown that precision measurements of the differential cross
section of the reaction can be obtained in a wide
angular and kinematical range. The individual determination of the moduli of
the electric and magnetic proton form factors will be possible up to a value of
momentum transfer squared of (GeV/c). The total cross section will be measured up to (GeV/c).
The results obtained from simulated events are compared to the existing data.
Sensitivity to the two photons exchange mechanism is also investigated.Comment: 12 pages, 4 tables, 8 figures Revised, added details on simulations,
4 tables, 9 figure
Feasibility studies of time-like proton electromagnetic form factors at PANDA at FAIR
Simulation results for future measurements of electromagnetic proton form
factors at \PANDA (FAIR) within the PandaRoot software framework are reported.
The statistical precision with which the proton form factors can be determined
is estimated. The signal channel is studied on the basis
of two different but consistent procedures. The suppression of the main
background channel, , is studied.
Furthermore, the background versus signal efficiency, statistical and
systematical uncertainties on the extracted proton form factors are evaluated
using two different procedures. The results are consistent with those of a
previous simulation study using an older, simplified framework. However, a
slightly better precision is achieved in the PandaRoot study in a large range
of momentum transfer, assuming the nominal beam conditions and detector
performance
Demulsification mechanism of asphaltene-stabilized water-in-oil emulsions by a polymeric ethylene oxide-propylene oxide demulsifier
The demulsification mechanism of asphaltene-stabilized water-in-toluene emulsions by an ethylene-oxide-propylene oxide (EO-PO) based polymeric demulsifier was studied. Demulsification efficiency was determined by bottle tests and correlated to the physicochemical properties of asphaltene interfacial films after demulsifier addition. From bottle tests and droplet coalescence experiments, the demulsifier showed an optimal performance at 2.3 ppm (mass basis) in toluene. At high concentrations, the demulsification performance deteriorated due to the intrinsic stabilizing capacity of the demulsifier, which was attributed to steric repulsion between water droplets. Addition of demulsifier was shown to soften the asphaltene film (i.e., reduce the viscoelastic moduli of asphaltene films) under both shear and compressional interfacial deformations. Study of the macrostructures and the chemical composition of asphaltene film at the toluene-water interface after demulsifier addition demonstrated gradual penetration of the demulsifier into the asphaltene film. Demulsifier penetration in the asphaltene film changed the asphaltene interfacial mobility and morphology, as probed with Brewster angle and atomic force microscopy
Study of doubly strange systems using stored antiprotons
Bound nuclear systems with two units of strangeness are still poorly known despite their importance for many strong interaction phenomena. Stored antiprotons beams in the GeV range represent an unparalleled factory for various hyperon-antihyperon pairs. Their outstanding large production probability in antiproton collisions will open the floodgates for a series of new studies of systems which contain two or even more units of strangeness at the PâŸANDA experiment at FAIR. For the first time, high resolution Îł-spectroscopy of doubly strange ÎÎ-hypernuclei will be performed, thus complementing measurements of ground state decays of ÎÎ-hypernuclei at J-PARC or possible decays of particle unstable hypernuclei in heavy ion reactions. High resolution spectroscopy of multistrange Îâ-atoms will be feasible and even the production of Ωâ-atoms will be within reach. The latter might open the door to the |S|=3 world in strangeness nuclear physics, by the study of the hadronic Ωâ-nucleus interaction. For the first time it will be possible to study the behavior of ÎâŸ+ in nuclear systems under well controlled conditions
Feasibility study for the measurement of Ïn transition distribution amplitudes at P ANDA in p âj /ÏÏ0 FEASIBILITY STUDY for the MEASUREMENT of ⯠B. SINGH et al. SINGH
The exclusive charmonium production process in pp annihilation with an associated Ï0 meson ppâJ/ÏÏ0 is studied in the framework of QCD collinear factorization. The feasibility of measuring this reaction through the J/Ïâe+e- decay channel with the AntiProton ANnihilation at DArmstadt (PANDA) experiment is investigated. Simulations on signal reconstruction efficiency as well as the background rejection from various sources including the ppâÏ+Ï-Ï0 and ppâJ/ÏÏ0Ï0 reactions are performed with PandaRoot, the simulation and analysis software framework of the PANDA experiment. It is shown that the measurement can be done at PANDA with significant constraining power under the assumption of an integrated luminosity attainable in four to five months of data taking at the maximum design luminosity. © 2017 American Physical Society