J. Benesch
A5046462000- Particle Accelerators and Free-Electron Lasers
- Particle physics theoretical and experimental studies
- Particle accelerators and beam dynamics
- Quantum Chromodynamics and Particle Interactions
- Superconducting Materials and Applications
- Nuclear physics research studies
- Dark Matter and Cosmic Phenomena
- Photocathodes and Microchannel Plates
- Polymer Surface Interaction Studies
- Particle Detector Development and Performance
- Electron and X-Ray Spectroscopy Techniques
- High-Energy Particle Collisions Research
- Crystallography and Radiation Phenomena
- Muon and positron interactions and applications
- Blood properties and coagulation
- Magnetic confinement fusion research
- Radiation Therapy and Dosimetry
- Advanced NMR Techniques and Applications
- Gyrotron and Vacuum Electronics Research
- Radiation Detection and Scintillator Technologies
- Platelet Disorders and Treatments
- Proteins in Food Systems
- Nuclear Physics and Applications
- Spacecraft and Cryogenic Technologies
- Radioactive Decay and Measurement Techniques
Thomas Jefferson National Accelerator Facility
2015-2024
University of Minho
2007-2013
Directorate-General for Research and Innovation
2013
European Commission
2013
Institute for Biotechnology and Bioengineering
2007-2010
Linköping University
2000-2007
Newport (United States)
2006
We report the first measurement of parity-violating asymmetry APV in elastic scattering polarized electrons from Pb208. is sensitive to radius neutron distribution (Rn). The result APV=0.656±0.060(stat)±0.014(syst) ppm corresponds a difference between radii and proton distributions Rn−Rp=0.33−0.18+0.16 fm provides electroweak observation skin which expected heavy, neutron-rich nucleus.Received 12 January 2012DOI:https://doi.org/10.1103/PhysRevLett.108.112502© 2012 American Physical Society
We have measured parity-violating asymmetries in elastic electron-proton scattering over the range of momentum transfers 0.12 < or =Q2 =1.0 GeV2. These asymmetries, arising from interference electromagnetic and neutral weak interactions, are sensitive to strange-quark contributions currents proton. The measurements were made at Jefferson Laboratory using a toroidal spectrometer detect recoiling protons liquid hydrogen target. results indicate nonzero, Q2 dependent, provide new information...
We report new measurements of the parity-violating asymmetry ${A}_{\mathrm{PV}}$ in elastic scattering 3 GeV electrons off hydrogen and $^{4}\mathrm{He}$ targets with $⟨{\ensuremath{\theta}}_{\mathrm{lab}}⟩\ensuremath{\approx}6.0\ifmmode^\circ\else\textdegree\fi{}$. The result is ${A}_{\mathrm{PV}}=\mathbf{(}+6.40\ifmmode\pm\else\textpm\fi{}0.23(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.12(\mathrm{syst})\mathbf{)}\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$....
The Q(weak) experiment has measured the parity-violating asymmetry in ep elastic scattering at Q(2)=0.025(GeV/c)(2), employing 145 μA of 89% longitudinally polarized electrons on a 34.4 cm long liquid hydrogen target Jefferson Lab. results experiment's commissioning run, constituting approximately 4% data collected experiment, are reported here. From these initial results, is A(ep)=-279±35 (stat) ± 31 (syst) ppb, which smallest and most precise ever scattering. small Q(2) this made possible...
We have measured parity-violating asymmetries in elastic electron-proton and quasielastic electron-deuteron scattering at ${Q}^{2}=0.22$ $0.63\text{ }\text{ }{\mathrm{GeV}}^{2}$. They are sensitive to strange quark contributions currents the nucleon axial-vector current. The results indicate of $\ensuremath{\lesssim}10%$ charge magnetic form factors these four-momentum transfers. also present first measurement anapole moment effects current
The Polarized Electrons for Positrons experiment at the injector of Continuous Electron Beam Accelerator Facility has demonstrated first time efficient transfer polarization from electrons to positrons produced by polarized bremsstrahlung radiation induced a electron beam in high-Z target. Positron up 82% have been measured an initial momentum 8.19 MeV/c, limited only polarization. This technique extends positron capabilities GeV MeV beams, and opens access physics wide community.
Abstract The solenoidal large intensity device (SoLID) is a new experimental apparatus planned for Hall A at the Thomas Jefferson National Accelerator Facility (JLab). SoLID will combine angular and momentum acceptance with capability to handle very high data rates luminosity. With slate of approved high-impact physics experiments, push JLab limit QCD frontier that exploit full potential its 12 GeV electron beam. In this paper, we present an overview rich program can be realized SoLID, which...
Surface modification of biomaterials is a way to tailor cell responses whilst retaining the bulk properties. In this work, chitosan membranes were prepared by solvent casting and treated with nitrogen or argon plasma at 20 W for 10-40 min. AFM indicated an increase in surface roughness as result ongoing etching process. XPS contact angle measurements showed different elemental compositions higher free energy. The MTS test direct assays L929 fibroblast line that treatment improved adhesion...
The parity-violating cross-section asymmetry in the elastic scattering of polarized electrons from unpolarized protons has been measured at a four-momentum transfer squared Q2 = 0.624 GeV and beam energy E =3.48 to be A_PV -23.80 +/- 0.78 (stat) 0.36 (syst) parts per million. This result is consistent with zero contribution strange quarks combination electric magnetic form factors G_E^s + 0.517 G_M^s 0.003 0.010 0.004 0.009 (ff), where third error due limits precision on electromagnetic...
Low protein adsorption is believed advantageous for blood-contacting materials and ethylene glycols (EG)-based polymeric compounds are often attached to surfaces this purpose. In the present study, of fibrinogen, serum, plasma were studied by ellipsometry on a series well-defined oligo(EG) terminated alkane-thiols self-assembled gold. The layers prepared with general structure HS-(CH2)15-CONH-EGn, where n = 2, 4, 6. Methoxy-terminated tri(EG) undecanethiol hydroxyl-terminated hexadecanethiol...
We have measured the beam-normal single-spin asymmetry $A_n$ in elastic scattering of 1-3 GeV transversely polarized electrons from $^1$H and for first time $^4$He, $^{12}$C, $^{208}$Pb. For $^1$H, $^4$He measurements are agreement with calculations that relate to imaginary part two-photon exchange amplitude including inelastic intermediate states. Surprisingly, $^{208}$Pb result is significantly smaller than corresponding prediction using same formalism. These results suggest a systematic...
Abstract Novel highly branched biodegradable macromolecular systems have been developed by grafting carboxymethylchitosan (CMCht) onto low generation poly(amidoamine) (PAMAM) dendrimers. Such structures organize into sphere‐like nanoparticles that are proposed to be used as carriers deliver bioactive molecules aimed at controlling the behavior of stem cells, namely their proliferation and differentiation. The did not exhibit significant cytotoxicity in range concentrations below 1 mg mL −1 ,...
The physics case and an experimental overview of the MOLLER (Measurement Of a Lepton Electroweak Reaction) experiment at 12 GeV upgraded Jefferson Lab are presented. A highlight Fundamental Symmetries subfield 2007 NSAC Long Range Plan was SLAC E158 measurement parity-violating asymmetry $A_{PV}$ in polarized electron-electron (M{\o}ller) scattering. proposed will improve on this result by factor five, yielding most precise weak mixing angle low or high energy anticipated over next decade....
Tests of the standard model particle physics rely on measurements with highly polarized electron beams. A new instrument achieves highest known precision for determining beam polarization low-energy (~1 GeV)
The parity-violating asymmetries between a longitudinally polarized electron beam and an unpolarized deuterium target have been measured recently. measurement covered two kinematic points in the deep-inelastic scattering region five nucleon resonance region. We provide here details of experimental setup, data analysis, results on all asymmetry measurements including those inclusive pion production beam-normal asymmetries. were used to extract electron-quark weak effective couplings, provided...