E. C. Aschenauer
A5013701003- High-Energy Particle Collisions Research
- Quantum Chromodynamics and Particle Interactions
- Particle physics theoretical and experimental studies
- Particle Accelerators and Free-Electron Lasers
- Nuclear physics research studies
- Particle Detector Development and Performance
- Atomic and Molecular Physics
- Nuclear reactor physics and engineering
- Superconducting Materials and Applications
- Stochastic processes and statistical mechanics
- Particle accelerators and beam dynamics
- Advanced Chemical Physics Studies
- Nuclear Physics and Applications
- Dark Matter and Cosmic Phenomena
- X-ray Spectroscopy and Fluorescence Analysis
- International Science and Diplomacy
- Advanced NMR Techniques and Applications
- Advancements in Photolithography Techniques
- Electron and X-Ray Spectroscopy Techniques
- Fusion materials and technologies
- Distributed and Parallel Computing Systems
- Muon and positron interactions and applications
- Magnetic confinement fusion research
- Silicon and Solar Cell Technologies
- Silicon Carbide Semiconductor Technologies
Brookhaven National Laboratory
2016-2025
University of Science and Technology of China
2024
South China Normal University
2024
Sejong University
2024
Brookhaven College
2023
Institute for Theoretical and Experimental Physics
2019
Trinity College Dublin
2019
Central China Normal University
2014-2018
Japan Atomic Energy Agency
2016
National Library of Luxembourg
2015
The summarizes much of particle physics and cosmology. Using data from previous editions, plus 2,717 new measurements 869 papers, we list, evaluate, average measured properties gauge bosons the recently discovered Higgs boson, leptons, quarks, mesons, baryons. We summarize searches for hypothetical particles such as supersymmetric particles, heavy bosons, axions, dark photons, etc. Particle search limits are listed in Summary Tables. give numerous tables, figures, formulae, reviews topics...
This report is based on a ten-week program Gluons and the quark sea at high-energies, which took place Institute for Nuclear Theory (INT) in Seattle Fall 2010. The principal aim of was to develop sharpen science case an Electron-Ion Collider (EIC), facility that will be able collide electrons positrons with polarized protons light heavy nuclei high energies, offering unprecedented possibilities in-depth studies quantum chromodynamics (QCD). organized around following four major themes: (i)...
Local parity-odd domains are theorized to form inside a quark-gluon plasma which has been produced in high-energy heavy-ion collisions. The local manifest themselves as charge separation along the magnetic field axis via chiral effect. experimental observation of previously reported for collisions at top RHIC energies. In this Letter, we present results beam-energy dependence correlations $\mathrm{Au}+\mathrm{Au}$ midrapidity center-of-mass energies 7.7, 11.5, 19.6, 27, 39, and 62.4 GeV from...
This White Paper presents an overview of the current status and future perspective QCD research, based on community inputs scientific conclusions from 2022 Hot Cold Town Meeting. We present progress made in last decade toward a deep understanding both fundamental structure sub-atomic matter nucleon nucleus cold QCD, hot heavy ion collisions. identify key questions research plausible paths to obtaining answers those near future, hence defining priorities our over coming decades.
In heavy-ion collision experiments, the global collectivity of final-state particles can be quantified by anisotropic flow coefficients (𝑣𝑛). The first-order coefficient, also referred to as directed (𝑣1), describes collective sideward motion produced and nuclear fragments in collisions. It carries information on very early stage collision, especially at large pseudorapidity (𝜂), where it is believed generated during passage time. Directed therefore probes onset bulk dynamics thermalization,...
The beam-spin asymmetry in hard electroproduction of photons has been measured. data have accumulated by the HERMES experiment at DESY using HERA 27.6 GeV longitudinally polarized positron beam and an unpolarized hydrogen-gas target. azimuthal distribution produced angle $\ensuremath{\varphi}$ relative to lepton scattering plane was determined with respect helicity state incoming beam. analyzing power $\mathrm{sin}\ensuremath{\varphi}$ moment measured be...
Results are reported from the HERMES experiment at HERA on a measurement of neutron spin structure function $g_1^n(x,Q^2)$ in deep inelastic scattering using 27.5 GeV longitudinally polarized positrons incident $^3$He internal gas target. The data cover kinematic range $0.023
This White Paper presents the science case of an Electron-Ion Collider (EIC), focused on structure and interactions gluon-dominated matter, with intent to articulate it broader nuclear community. It was commissioned by managements Brookhaven National Laboratory (BNL) Thomas Jefferson Accelerator Facility (JLab) objective presenting a summary scientific opportunities goals EIC as follow-up 2007 NSAC Long Range plan. document is culmination community-wide effort in following series workshops...
Single-spin asymmetries for pions and charged kaons are measured in semi-inclusive deep-inelastic scattering of positrons electrons off a transversely nuclear-polarized hydrogen target. The dependence the cross section on azimuthal angles target polarization (phi_S)and produced hadron (phi) is found to have substantial sin(phi+phi_S) modulation production pi+, pi- K+. This Fourier component can be interpreted terms non-zero transversity distribution functions favored disfavored Collins...
We present azimuthal angular correlations between charged hadrons and energy deposited in calorimeter towers central d+Au minimum bias p+p collisions at √sNN=200 GeV. The hadron is measured midrapidity |η|<0.35, the large rapidity (−3.7<η<−3.1, Au-going direction). An enhanced near-side correlation across |Δη|>2.75 observed collisions. Using event plane method applied to distribution, we extract anisotropy strength v2 for inclusive up pT=4.5 GeV/c. also measurement of identified π±...
A systematic study is presented for centrality, transverse momentum (${p}_{T}$), and pseudorapidity ($\ensuremath{\eta}$) dependence of the inclusive charged hadron elliptic flow (${v}_{2}$) at midrapidity ($|\ensuremath{\eta}|<1.0$) in $\mathrm{Au}+\mathrm{Au}$ collisions $\sqrt{{s}_{NN}}=7.7$, 11.5, 19.6, 27, 39 GeV. The results obtained with different methods, including correlations event plane reconstructed a region separated by large gap four-particle cumulants (${v}_{2}{4}$), are to...
Measurements of the elliptic flow, ${v}_{2}$, identified hadrons (${\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}$, ${K}^{\ifmmode\pm\else\textpm\fi{}}$, ${K}_{s}^{0}$, $p$, $\overline{p}$, $\ensuremath{\phi}$, $\ensuremath{\Lambda}$, $\overline{\ensuremath{\Lambda}}$, ${\ensuremath{\Xi}}^{\ensuremath{-}}$, ${\overline{\ensuremath{\Xi}}}^{+}$, ${\ensuremath{\Omega}}^{\ensuremath{-}}$, ${\overline{\ensuremath{\Omega}}}^{+}$) in $\mathrm{Au}+\mathrm{Au}$ collisions at...
We provide an assessment of the energy dependence key measurements within scope machine parameters for a US based electron-ion collider (EIC) outlined in EIC White Paper. first examine importance physics underlying these context outstanding questions nuclear science. then demonstrate, through detailed simulations measurements, that likelihood transformational scientific insights is greatly enhanced by making range and reach as large practically feasible.
We report measurements of charmed-hadron $({D}^{0},{D}^{*})$ production cross sections at midrapidity in $p+p$ collisions a center-of-mass energy 200 GeV by the STAR experiment. Charmed hadrons were reconstructed via hadronic decays ${D}^{0}\ensuremath{\rightarrow}{K}^{\ensuremath{-}}{\ensuremath{\pi}}^{+}$, ${D}^{*+}\ensuremath{\rightarrow}{D}^{0}{\ensuremath{\pi}}^{+}\ensuremath{\rightarrow}{K}^{\ensuremath{-}}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{+}$ and their charge conjugates,...
We report the first measurement of elliptic anisotropy (v_{2}) charm meson D^{0} at midrapidity (|y|<1) in Au+Au collisions sqrt[s_{NN}]=200 GeV. The was conducted by STAR experiment RHIC utilizing a new high-resolution silicon tracker. measured v_{2} 0%-80% centrality can be described viscous hydrodynamic calculation for transverse momentum (p_{T}) less than 4 GeV/c. as function kinetic energy (m_{T}-m_{0}, where m_{T}=sqrt[p_{T}^{2}+m_{0}^{2}]) is consistent with that light mesons 10%-40%...
We report measurements of the third harmonic coefficient azimuthal anisotropy, ${v}_{3}$, known as triangular flow. The analysis is for charged particles in Au+Au collisions at $\sqrt{{s}_{\mathit{NN}}}=200$ GeV, based on data from STAR experiment BNL Relativistic Heavy Ion Collider. Two-particle correlations a function their pseudorapidity separation are fit with narrow and wide Gaussians. Measurements flow extracted Gaussian, two-particle cumulants gap, also event plane methods large gap...
We report a new measurement of the midrapidity inclusive jet longitudinal double-spin asymmetry, A_{LL}, in polarized pp collisions at center-of-mass energy sqrt[s]=200 GeV. The STAR data place stringent constraints on parton distribution functions extracted next-to-leading order from global analyses deep-inelastic scattering (DIS), semi-inclusive DIS, and RHIC data. measured asymmetries provide evidence 3σ level for positive gluon polarization Bjorken-x region x>0.05.
Time and again, spin has been a key element in the exploration of fundamental physics. Spin-dependent observables have often revealed deficits assumed theoretical framework led to novel developments concepts. Spin is exploited many parity-violating experiments searching for physics beyond Standard Model or studying nature nucleon-nucleon forces. The RHIC program plays special role this grand scheme: it uses study how complex many-body system such as proton arises from dynamics QCD. Many...
We present results of analyses two-pion interferometry in $\mathrm{Au}+\mathrm{Au}$ collisions at $\sqrt{{s}_{\mathit{NN}}}=7.7$, 11.5, 19.6, 27, 39, 62.4, and 200 GeV measured the STAR detector as part BNL Relativistic Heavy Ion Collider Beam Energy Scan program. The extracted correlation lengths (Hanbury-Brown--Twiss radii) are studied a function beam energy, azimuthal angle relative to reaction plane, centrality, transverse mass (${m}_{T}$) particles. analysis allows extraction...
The STAR Collaboration reports the measurement of semi-inclusive distributions charged-particle jets recoiling from a high transverse momentum hadron trigger, in central and peripheral $\mathrm{Au}+\mathrm{Au}$ collisions at $\sqrt{{s}_{\mathrm{NN}}}=200$ GeV. Charged are reconstructed with anti-${k}_{\mathrm{T}}$ algorithm for jet radii $R$ between 0.2 0.5 low infrared cutoff track constituents (${p}_{\mathrm{T}}>0.2 \mathrm{GeV}/\mathrm{c}$). A novel mixed-event technique is used to...
Dihadron angular correlations in d+Au collisions at sNN=200GeV are reported as a function of the measured zero-degree calorimeter neutral energy and forward charged hadron multiplicity Au-beam direction. A finite correlated yield is observed large relative pseudorapidity (Δη) on near side (i.e. azimuth Δϕ∼0). This Δη appears to scale with dominant, primarily jet-related, away-side (Δϕ∼π) yield. The Fourier coefficients Δϕ correlation, Vn=〈cosnΔϕ〉, have strong dependence. In addition, it...
Global polarization of Ξ and Ω hyperons has been measured for the first time in Au+Au collisions at sqrt[s_{NN}]=200 GeV. The measurements Ξ^{-} Ξ[over ¯]^{+} hyperon have performed by two independent methods, via analysis angular distribution daughter particles parity violating weak decay Ξ→Λ+π, as well measuring Λ hyperon, polarized transfer from its parent. polarization, obtained combining results methods averaged over ¯]^{+}, is to be ⟨P_{Ξ}⟩=0.47±0.10(stat)±0.23(syst)% collision...
Rapidity-odd directed-flow measurements at midrapidity are presented for $\mathrm{\ensuremath{\Lambda}}$, $\overline{\mathrm{\ensuremath{\Lambda}}}$, ${K}^{\ifmmode\pm\else\textpm\fi{}}$, ${K}_{s}^{0}$, and $\ensuremath{\phi}$ $\sqrt{{s}_{NN}}=7.7$, 11.5, 14.5, 19.6, 27, 39, 62.4, 200 GeV in $\mathrm{Au}+\mathrm{Au}$ collisions recorded by the Solenoidal Tracker detector Relativistic Heavy Ion Collider. These greatly expand scope of data available to constrain models with differing...
We report the first measurement of rapidity-odd directed flow ($v_{1}$) for $D^{0}$ and $\overline{D^{0}}$ mesons at mid-rapidity ($|y| < 0.8$) in Au+Au collisions $\sqrt{s_{\rm NN}}$ = 200\,GeV using STAR detector Relativistic Heavy Ion Collider. In 10--80\% collisions, slope $v_{1}$ rapidity dependence ($dv_{1}/dy$), averaged over mesons, is -0.080 $\pm$ 0.017 (stat.) 0.016 (syst.) transverse momentum $p_{\rm T}$ above 1.5~GeV/$c$. The absolute value $D^0$-meson $dv_1/dy$ about 25 times...