S. M. Gibson
- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Quantum Chromodynamics and Particle Interactions
- Particle Detector Development and Performance
- Dark Matter and Cosmic Phenomena
- Cosmology and Gravitation Theories
- Computational Physics and Python Applications
- Neutrino Physics Research
- Particle Accelerators and Free-Electron Lasers
- Magnetic confinement fusion research
- Radiation Detection and Scintillator Technologies
- Superconducting Materials and Applications
- Astrophysics and Cosmic Phenomena
- Nuclear reactor physics and engineering
- Fusion materials and technologies
- Particle accelerators and beam dynamics
- Black Holes and Theoretical Physics
- Distributed and Parallel Computing Systems
- Laser-Plasma Interactions and Diagnostics
- Nuclear Physics and Applications
- Medical Imaging Techniques and Applications
- Stochastic processes and statistical mechanics
- Atomic and Subatomic Physics Research
- Advanced Optical Sensing Technologies
- Radiation Therapy and Dosimetry
Royal Holloway University of London
2016-2025
Valparaiso University
2016-2025
AGH University of Krakow
2013-2024
University of North Carolina at Chapel Hill
2024
Ball State University
2022-2024
Argonne National Laboratory
2022-2024
Central China Normal University
2024
Frankfurt Institute for Advanced Studies
2022-2024
Creighton University
2022-2024
Guangxi Normal University
2024
We present measurements of bulk properties the matter produced in Au+Au collisions at $\sqrt{s_{NN}}=$ 7.7, 11.5, 19.6, 27, and 39 GeV using identified hadrons ($\pi^\pm$, $K^\pm$, $p$ $\bar{p}$) from STAR experiment Beam Energy Scan (BES) Program Relativistic Heavy Ion Collider (RHIC). Midrapidity ($|y|<$0.1) results for multiplicity densities $dN/dy$, average transverse momenta $\langle p_T \rangle$ particle ratios are presented. The chemical kinetic freeze-out dynamics these energies...
We report the beam energy (sqrt[sNN]=7.7-200 GeV) and collision centrality dependence of mean (M), standard deviation (σ), skewness (S), kurtosis (κ) net-proton multiplicity distributions in Au+Au collisions. The measurements are carried out by STAR experiment at midrapidity (|y|<0.5) within transverse momentum range 0.4<pT<0.8 GeV/c first phase Beam Energy Scan program Relativistic Heavy Ion Collider. These important for understanding quantum chromodynamic diagram. products moments, Sσ κσ2,...
We report the first measurements of moments -- mean ($M$), variance ($\sigma^{2}$), skewness ($S$) and kurtosis ($\kappa$) net-charge multiplicity distributions at mid-rapidity in Au+Au collisions seven energies, ranging from $\sqrt {{s_{\rm NN}}}$= 7.7 to 200 GeV, as a part Beam Energy Scan program RHIC. The are related thermodynamic susceptibilities net-charge, sensitive proximity QCD critical point. compare products moments, $\sigma^{2}/M$, $S\sigma$ $\kappa\sigma^{2}$ with expectations...
Global polarization of $\Lambda$ hyperons has been measured to be the order a few tenths percent in Au+Au collisions at $\sqrt{s_{_{NN}}}$ = 200 GeV, with no significant difference between and $\bar{\Lambda}$. These new results reveal collision energy dependence global together previously observed 7.7 -- 62.4 GeV indicate noticeable vorticity medium created non-central heavy-ion highest RHIC energy. The signal is rough quantitative agreement theoretical predictions from hydrodynamic model...
Rapidity-odd directed flow (v1) measurements for charged pions, protons, and antiprotons near midrapidity (y=0) are reported in sNN=7.7, 11.5, 19.6, 27, 39, 62.4, 200 GeV Au+Au collisions as recorded by the STAR detector at Relativistic Heavy Ion Collider. At intermediate impact parameters, proton net-proton slope parameter dv1/dy|y=0 shows a minimum between 11.5 19.6 GeV. In addition, changes sign twice 7.7 39 The results qualitatively resemble predictions of hydrodynamic model with...
We report the first measurement of charmed-hadron (D(0)) production via hadronic decay channel (D(0) → K(-) + π(+)) in Au+Au collisions at sqrt[s(NN)] = 200 GeV with STAR experiment. The charm cross section per nucleon-nucleon collision midrapidity scales number binary collisions, N(bin), from p+p to central collisions. D(0) meson yields Au are strongly suppressed compared those scaled by for transverse momenta p(T) > 3 GeV/c, demonstrating significant energy loss quarks hot and dense...
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...
The Λ (Λ[over ¯]) hyperon polarization along the beam direction has been measured in Au+Au collisions at sqrt[s_{NN}]=200 GeV, for first time heavy-ion collisions. dependence on hyperons' emission angle relative to elliptic flow plane exhibits a second harmonic sine modulation, indicating quadrupole pattern of vorticity component direction, expected due flow. is found increase more peripheral collisions, and shows no strong transverse momentum (p_{T}) p_{T} greater than 1 GeV/c. magnitude...
Non-monotonic variation with collision energy ($\sqrt{s_{\rm NN}}$) of the moments net-baryon number distribution in heavy-ion collisions, related to correlation length and susceptibilities system, is suggested as a signature for Quantum Chromodynamics (QCD) critical point. We report first evidence non-monotonic kurtosis times variance net-proton (proxy number) function \rootsnn 3.1$\sigma$ significance, head-on (central) gold-on-gold (Au+Au) collisions measured using STAR detector at RHIC....
Abstract High energy collisions at the High-Luminosity Large Hadron Collider (LHC) produce a large number of particles along beam collision axis, outside acceptance existing LHC experiments. The proposed Forward Physics Facility (FPF), to be located several hundred meters from ATLAS interaction point and shielded by concrete rock, will host suite experiments probe standard model (SM) processes search for physics beyond (BSM). In this report, we review status civil engineering plans explore...
The chiral magnetic effect (CME) is predicted to occur as a consequence of local violation $\mathcal{P}$ and $\mathcal{C}P$ symmetries the strong interaction amidst electromagnetic field generated in relativistic heavy-ion collisions. Experimental manifestation CME involves separation positively negatively charged hadrons along direction field. Previous measurements CME-sensitive charge-separation observables remain inconclusive because large background contributions. To better control...
Abstract Neutrinos are copiously produced at particle colliders, but no collider neutrino has ever been detected. Colliders produce both neutrinos and anti-neutrinos of all flavors very high energies, they therefore highly complementary to those from other sources. FASER, the Forward Search Experiment LHC, is ideally located provide first detection study neutrinos. We investigate prospects for studies with FASER $$\nu $$ <mml:math...
The Breit-Wheeler process which produces matter and anti-matter from photon collisions is investigated experimentally through the observation of 6085 exclusive electron-positron pairs in ultra-peripheral Au+Au at $\sqrt{s_{_{NN}}}=200$ GeV. measurements reveal a large fourth-order angular modulation $\cos{4\Delta\phi}=(16.8\pm2.5)\%$ smooth invariant mass distribution absent vector mesons ($\phi$, $\omega$ $\rho$) experimental limit $\le 0.2\%$ observed yields. differential cross section as...
We report a systematic measurement of cumulants, $C_{n}$, for net-proton, proton and antiproton multiplicity distributions, correlation functions, $\kappa_n$, distributions up to the fourth order in Au+Au collisions at $\sqrt{s_{\mathrm {NN}}}$ = 7.7, 11.5, 14.5, 19.6, 27, 39, 54.4, 62.4 200 GeV. The $C_{n}$ $\kappa_n$ are presented as function collision energy, centrality kinematic acceptance rapidity, $y$, transverse momentum, $p_{T}$. data were taken during first phase Beam Energy Scan...
We report the first direct observation of neutrino interactions at a particle collider experiment. Neutrino candidate events are identified in 13.6 TeV center-of-mass energy pp collision dataset 35.4 fb^{-1} using active electronic components FASER detector Large Hadron Collider. The candidates required to have track propagating through entire length and be consistent with muon charged-current interaction. infer 153_{-13}^{+12} significance 16 standard deviations above background-only...
The deconfined quark-gluon plasma (QGP) created in relativistic heavy-ion collisions enables the exploration of fundamental properties matter under extreme conditions. Noncentral can produce strong magnetic fields on order <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:msup><a:mn>10</a:mn><a:mn>18</a:mn></a:msup><a:mtext> </a:mtext><a:mtext> </a:mtext><a:mi mathvariant="normal">G</a:mi></a:math>, which offers a probe into electrical conductivity QGP. In particular,...
High fusion power experiments using DT mixtures in ELM-free H mode and optimized shear regimes JET are reported. A of 16.1 MW has been produced an at 4.2 MA/3.6 T. The transient value the amplification factor was 0.95±0.17, consistent with high nDT(0)τEdiaTi(0) = 8.7 × 1020±20% m-3 s keV, maintained for about half energy confinement time until excessive edge pressure gradients resulted discharge termination by MHD instabilities. ratio DD to powers (from separate but otherwise similar...
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...
The ATLAS collaboration will upgrade its semiconductor pixel tracking detector with a new Insertable B-layer (IBL) between the existing and vacuum pipe of Large Hadron Collider. extreme operating conditions at this location have necessitated development radiation hard sensor technologies front-end readout chip, called FE-I4. Planar sensors 3D been investigated to equip layer, prototype modules using FE-I4A fabricated characterized 120 GeV pions CERN SPS 4 positrons DESY, before after module...
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...
Fluctuations of conserved quantities such as baryon number, charge, and strangeness are sensitive to the correlation length hot dense matter created in relativistic heavy-ion collisions can be used search for QCD critical point. We report first measurements moments net-kaon multiplicity distributions Au+Au at sNN=7.7, 11.5, 14.5, 19.6, 27, 39, 62.4, 200 GeV. The collision centrality energy dependence mean (M), variance (σ2), skewness (S), kurtosis (κ) well ratio σ2/M products Sσ κσ2...