W. Lorenzon
A5091349820- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- Atomic and Subatomic Physics Research
- High-Energy Particle Collisions Research
- Dark Matter and Cosmic Phenomena
- Nuclear Physics and Applications
- Advanced NMR Techniques and Applications
- Nuclear physics research studies
- Particle Accelerators and Free-Electron Lasers
- Quantum, superfluid, helium dynamics
- Particle Detector Development and Performance
- Superconducting Materials and Applications
- Particle accelerators and beam dynamics
- Neutrino Physics Research
- Radiation Detection and Scintillator Technologies
- Astronomy and Astrophysical Research
- CCD and CMOS Imaging Sensors
- Advanced Semiconductor Detectors and Materials
- Electron and X-Ray Spectroscopy Techniques
- Infrared Target Detection Methodologies
- Atomic and Molecular Physics
- Calibration and Measurement Techniques
- Stellar, planetary, and galactic studies
- Photocathodes and Microchannel Plates
- X-ray Spectroscopy and Fluorescence Analysis
Michigan United
2006-2024
Argonne National Laboratory
2013-2024
University of Michigan
2015-2024
University of Edinburgh
2024
University of Wisconsin–Madison
2021
University of Basel
1987-2020
University of Illinois Urbana-Champaign
2019
Ann Arbor Center for Independent Living
2002-2015
Shanghai Jiao Tong University
2015
Fermi National Accelerator Laboratory
2010-2012
We report the WIMP dark matter search results using first physics-run data of PandaX-II 500 kg liquid xenon dual-phase time-projection chamber, operating at China JinPing Underground Laboratory. No candidate is identified above background. In combination with set during commissioning run, a total exposure 3.3$\times10^4$ kg-day,the most stringent limit to spin-independent interaction between ordinary and for range mass 3.5 1000 GeV/c$^2$. The best upper on scattering cross section found...
Single-spin asymmetries for semi-inclusive electroproduction of charged pions in deep-inelastic scattering positrons are measured the first time with transverse target polarization. The asymmetry depends on azimuthal angles both pion ($\ensuremath{\phi}$) and spin axis (${\ensuremath{\phi}}_{S}$) about virtual-photon direction relative to lepton plane. extracted Fourier component $\mathbf{⟨}\mathrm{sin}(\ensuremath{\phi}+{\ensuremath{\phi}}_{S}){\mathbf{⟩}}_{UT}^{\ensuremath{\pi}}$ is a...
Precise measurements of the spin structure functions proton ${g}_{1}^{p}(x,{Q}^{2})$ and deuteron ${g}_{1}^{d}(x,{Q}^{2})$ are presented over kinematic range $0.0041\ensuremath{\le}x\ensuremath{\le}0.9$ $0.18\text{ }\text{ }{\mathrm{GeV}}^{2}\ensuremath{\le}{Q}^{2}\ensuremath{\le}20\text{ }{\mathrm{GeV}}^{2}$. The data were collected at HERMES experiment DESY, in deep-inelastic scattering 27.6 GeV longitudinally polarized positrons off hydrogen deuterium gas targets internal to HERA storage...
Azimuthal single-spin asymmetries of lepto-produced pions and charged kaons were measured on a transversely polarized hydrogen target. Evidence for naive-T-odd, transverse-momentum-dependent parton distribution function is deduced from non-vanishing Sivers effects pi+, pi0, K+, K-, as well in the difference pi+ pi- cross sections.
LUX-ZEPLIN (LZ) is a next-generation dark matter direct detection experiment that will operate 4850 feet underground at the Sanford Underground Research Facility (SURF) in Lead, South Dakota, USA. Using two-phase xenon detector with an active mass of 7 tonnes, LZ search primarily for low-energy interactions weakly interacting massive particles (WIMPs), which are hypothesized to make up our galactic halo. In this paper, projected WIMP sensitivity presented based on latest background estimates...
Polarized deep-inelastic scattering data on longitudinally polarized hydrogen and deuterium targets have been used to determine double-spin asymmetries of cross sections. Inclusive semi-inclusive for the production positive negative pions from were obtained in a reanalysis previously published data. kaons measured target. The separate helicity densities up down quarks anti-up, anti-down, strange sea computed these “leading order” QCD analysis. polarization up-quark is that down-quark...
We report on precision measurements of the elastic cross section for electron-proton scattering performed in Hall C at Jefferson Lab. The were made 28 distinct kinematic settings covering a range momentum transfer $0.4<{Q}^{2}<5.5\phantom{\rule{0.3em}{0ex}}{(\mathrm{GeV}∕c)}^{2}$. These represent significant contribution to world's data set ${Q}^{2}$ range, where large discrepancy currently exists between ratio electric magnetic proton form factors extracted from previous and that recently...
Single-spin asymmetries for pions and charged kaons are measured in semi-inclusive deep-inelastic scattering of positrons electrons off a transversely nuclear-polarized hydrogen target. The dependence the cross section on azimuthal angles target polarization (phi_S)and produced hadron (phi) is found to have substantial sin(phi+phi_S) modulation production pi+, pi- K+. This Fourier component can be interpreted terms non-zero transversity distribution functions favored disfavored Collins...
Multiplicities in semi-inclusive deep-inelastic scattering are presented for each charge state of ${\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}$ and ${\mathrm{K}}^{\ifmmode\pm\else\textpm\fi{}}$ mesons. The data were collected by the HERMES experiment at HERA storage ring using 27.6 GeV electron positron beams incident on a hydrogen or deuterium gas target. results as function kinematic quantities ${x}_{\mathrm{B}}$, ${Q}^{2}$, $z$, ${P}_{h\ensuremath{\perp}}$. They represent unique set...
The momentum and helicity density distributions of the strange quark sea in nucleon are obtained leading order from charged-kaon production deep-inelastic scattering on deuteron. extracted spin-averaged K+/- multiplicities, inclusive double-spin asymmetries for polarized positrons by a deuterium target. shape distribution is softer than that average ubar dbar quarks. In region measurement 0.02 < x 0.6 Q^2 > 1.0 GeV^2, zero within experimental uncertainties.
The cross section for quasielastic $^{12}\mathrm{C}$(e,e'p) scattering has been measured at momentum transfer ${\mathit{Q}}^{2}$=1, 3, 5, and 6.8 (GeV/c${)}^{2}$. results are consistent with from a single nucleon as the dominant process. nuclear transparency is obtained compared theoretical calculations that incorporate color effects. No significant rise of ${\mathit{Q}}^{2}$ observed.
The azimuthal cos{\phi} and cos2{\phi} modulations of the distribution hadrons produced in unpolarized semi-inclusive deep-inelastic scattering electrons positrons off hydrogen deuterium targets have been measured HERMES experiment. For first time these were determined a four-dimensional kinematic space for positively negatively charged pions kaons separately, as well unidentified hadrons. These dependences are sensitive to transverse motion polarization quarks within nucleon via, e.g.,...
Beam-helicity and beam-charge asymmetries in the hard exclusive leptoproduction of real photons from an unpolarised hydrogen target by a 27.6 GeV lepton beam are extracted HERMES data set 2006-2007 using missing-mass event selection technique. The asymmetry amplitudes this more precise than those earlier 1996-2005 previously analysed same manner HERMES. results two sets compatible with each other. Results these combined constitute most amplitude measurements made kinematic region
We present the results of a search for weakly interacting massive particles (WIMPs) from commissioning run PandaX-II experiment located at China Jinping Underground Laboratory. A WIMP data set with an exposure $306\ifmmode\times\else\texttimes\fi{}19.1\text{ }\text{ }\mathrm{kg}\text{\ensuremath{-}}\text{day}$ was taken, while its dominant $^{85}\mathrm{Kr}$ background used as electron recoil calibration. No candidates are identified, and 90% upper limit is on spin-independent elastic...
We present a measurement of the longitudinal spin asymmetry A(||) in photoproduction pairs hadrons with high transverse momentum p(T). Data were accumulated by HERMES experiment using 27.5 GeV polarized positron beam and hydrogen target internal to HERA storage ring. For h(+)h(-) p(h(1))(T)>1.5 GeV/c p(h(2))(T)>1.0 GeV/c, measured is = -0. 28+/-0.12(stat)+/-0.02(syst). This negative value contrast positive asymmetries typically deep inelastic scattering from protons, interpreted arise gluon...
We report a measurement of the asymmetry in spin-dependent quasielastic scattering longitudinally polarized electrons from He3 target. The neutron magnetic form factor GMn has been extracted measured based on recent PWIA calculations using spectral functions. Our determination at Q2=0.19 (GeV/c)2 agrees with dipole parametrization. This experiment represents first electron scattering.DOI:https://doi.org/10.1103/PhysRevC.50.R546©1994 American Physical Society
Double-spin asymmetries of semiinclusive cross sections for the production identified pions and kaons have been measured in deep inelastic scattering polarized positrons on a deuterium target. Five helicity distributions including those three sea quark flavors were extracted from these data together with reanalyzed previous hydrogen These are consistent zero all flavors. A recently predicted flavor asymmetry polarization light appears to be disfavored by data.