M. Daugherity
A5044713943- High-Energy Particle Collisions Research
- Quantum Chromodynamics and Particle Interactions
- Particle physics theoretical and experimental studies
- Nuclear reactor physics and engineering
- Stochastic processes and statistical mechanics
- Nuclear physics research studies
- Particle Accelerators and Free-Electron Lasers
- Theoretical and Computational Physics
- Particle accelerators and beam dynamics
- Dark Matter and Cosmic Phenomena
- Superconducting Materials and Applications
- Magnetic confinement fusion research
- Markov Chains and Monte Carlo Methods
- Particle Detector Development and Performance
- Fusion materials and technologies
- Neutrino Physics Research
- X-ray Spectroscopy and Fluorescence Analysis
- Cold Atom Physics and Bose-Einstein Condensates
- Geomagnetism and Paleomagnetism Studies
- Pulsars and Gravitational Waves Research
- Appendicitis Diagnosis and Management
- Computational Physics and Python Applications
- Atomic and Subatomic Physics Research
- Pediatric Urology and Nephrology Studies
- Gas Dynamics and Kinetic Theory
Abilene Christian University
2015-2024
Augustana University
2023
Indian Institute of Technology Patna
2023
PHENIX laboratory
2023
Texas A&M University
2023
Central China Normal University
2020-2022
Joint Institute for Nuclear Research
2021
Eötvös Loránd University
2020
Bridge University
2020
Yamagata University
2019
Identified charged-particle spectra of ${\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}$, ${K}^{\ifmmode\pm\else\textpm\fi{}}$, $p$, and $\overline{p}$ at midrapidity ($|y|<0.1$) measured by the $\mathit{dE}/\mathit{dx}$ method in STAR (solenoidal tracker BNL Relativistic Heavy Ion Collider) time projection chamber are reported for $\mathit{pp}$ $d+\mathrm{Au}$ collisions $\sqrt{{s}_{\mathit{NN}}}=200$ GeV $\mathrm{Au}+\mathrm{Au}$ 62.4, 130, 200 GeV. Average transverse momenta, total...
Parity-odd domains, corresponding to nontrivial topological solutions of the QCD vacuum, might be created during relativistic heavy-ion collisions. These domains are predicted lead charge separation quarks along system's orbital momentum axis. We investigate a three-particle azimuthal correlator which is $\mathcal{P}$ even observable, but directly sensitive effect. report measurements charged hadrons near center-of-mass rapidity with this observable in $\mathrm{Au}+\mathrm{Au}$ and...
The STAR collaboration at the BNL Relativistic Heavy-Ion Collider (RHIC) reports measurements of inclusive yield nonphotonic electrons, which arise dominantly from semileptonic decays heavy flavor mesons, over a broad range transverse momenta ($1.2<{p}_{T}<10\text{ }\text{ }\mathrm{GeV}/c$) in $p+p$, $d+\mathrm{Au}$, and $\mathrm{Au}+\mathrm{Au}$ collisions $\sqrt{{s}_{\mathrm{NN}}}=200\text{ }\mathrm{GeV}$. electron exhibits an unexpectedly large suppression central high ${p}_{T}$,...
We present strange particle spectra and yields measured at midrapidity in $\sqrt{s}=200$ GeV proton-proton ($p+p$) collisions the BNL Relativistic Heavy Ion Collider (RHIC). find that previously observed universal transverse mass (${m}_{T}\ensuremath{\equiv}\sqrt{{{p}_{T}}^{2}+{m}^{2}}$) scaling of hadron production $p+p$ seems to break down higher ${m}_{T}$ there is a difference shape spectrum between baryons mesons. observe antibaryon baryon ratios near unity for \ensuremath{\Lambda}...
Parity ($\mathcal{P}$)-odd domains, corresponding to nontrivial topological solutions of the QCD vacuum, might be created during relativistic heavy-ion collisions. These domains are predicted lead charge separation quarks along orbital momentum system in noncentral To study this effect, we investigate a three-particle mixed-harmonics azimuthal correlator which is $\mathcal{P}$-even observable, but directly sensitive charge-separation effect. We report measurements observable using STAR...
The STAR Collaboration at the Relativistic Heavy Ion Collider presents a systematic study of high-transverse-momentum charged-di-hadron correlations small azimuthal pair separation $\ensuremath{\Delta}\ensuremath{\phi}$ in $d+\mathrm{Au}$ and central $\mathrm{Au}+\mathrm{Au}$ collisions $\sqrt{{s}_{\mathit{NN}}}=200$ GeV. Significant correlated yield for pairs with large longitudinal $\ensuremath{\Delta}\ensuremath{\eta}$ is observed collisions, contrast to collisions. associated...
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....
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...
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...
The strong force, as one of the four fundamental forces at work in universe, governs interactions quarks and gluons, binds together atomic nucleus. Notwithstanding decades progress since Yukawa first developed a description force between nucleons terms meson exchange, full understanding interaction remains major challenge modern science. One remaining difficulty arises from non-perturbative nature which leads to phenomenon quark confinement distance scales on order size proton. Here we show...
Transverse momentum spectra of pi+/-, p, and p up to 12 GeV/c at midrapidity in centrality selected Au + collisions square root sNN=200 GeV are presented. In central collisions, both pi +/- p(p) show significant suppression with respect binary scaling pT approximately >4 GeV/c. Protons antiprotons less suppressed than the range 1.5 < 6 The pi-/pi+ p/p ratios most a weak dependence no dependence. p/pi approach values d >5 results high indicate that partonic sources have similar energy loss...
We present STAR results on the elliptic flow ${v}_{2}$ of charged hadrons, strange and multistrange particles from $\sqrt{{s}_{\mathit{NN}}}=200$ GeV Au+Au collisions at BNL Relativistic Heavy Ion Collider (RHIC). The detailed study centrality dependence over a broad transverse momentum range is presented. Comparisons different analysis methods are made in order to estimate systematic uncertainties. To discuss nonflow effect, we have performed first with Lee-Yang zero method for...
The STAR Collaboration at the Relativistic Heavy Ion Collider reports measurements of azimuthal correlations high transverse momentum (pT) charged hadrons in Au+Au collisions higher pT than reported previously. As is increased, a narrow, back-to-back peak emerges above decreasing background, providing clear dijet signal for all collision centralities studied. Using these correlations, we perform systematic study production and suppression nuclear collisions, new constraints on mechanisms...
Measurements of two-particle correlations on angular difference variables ${\ensuremath{\eta}}_{1}\ensuremath{-}{\ensuremath{\eta}}_{2}$ (pseudorapidity) and ${\ensuremath{\phi}}_{1}\ensuremath{-}{\ensuremath{\phi}}_{2}$ (azimuth) are presented for all primary charged hadrons with transverse momentum $0.15\ensuremath{\le}{p}_{t}\ensuremath{\le}2$ GeV/$c$ $|\ensuremath{\eta}|\ensuremath{\le}1.3$ from Au-Au collisions at $\sqrt{{s}_{\mathit{NN}}}=130$ GeV. Large-amplitude observed over a broad...
We present the scaling properties of Lambda, Xi, and Omega in midrapidity Au+Au collisions at Brookhaven National Laboratory Relativistic Heavy Ion Collider sqrt[s_{NN}]=200 GeV. The yield multistrange baryons per participant nucleon increases from peripheral to central more rapidly than that indicating an increase strange-quark density matter produced. strange phase-space occupancy factor gamma_{s} approaches unity for most collisions. Moreover, nuclear modification factors p, Xi are...
We present first measurements of the $\phi$-meson elliptic flow ($v_{2}(p_{T})$) and high statistics $p_{T}$ distributions for different centralities from $\sqrt{s_{NN}}$ = 200 GeV Au+Au collisions at RHIC. In minimum bias $v_{2}$ $\phi$ meson is consistent with trend observed mesons. The ratio yields $\Omega$ to those as a function transverse momentum model based on recombination thermal $s$ quarks up $p_{T}\sim 4$ GeV/$c$, but disagrees higher momenta. nuclear modification factor...
Measurements of the production forward π0 mesons from p+p and d+Au collisions at √sNN=200 GeV are reported. The yield generally agrees with next-to-leading order perturbative QCD calculations. per binary collision is suppressed as η increases, decreasing to ∼30% ⟨η⟩=4.00, well below shadowing expectations. Exploratory measurements azimuthal correlations charged hadrons η≈0 show a recoil peak in that low pion energy. These observations qualitatively consistent saturation picture low-x gluon...
We report on the first measurement of elliptic flow v2(pT) multistrange baryons Xi- +Xi+ and Omega- + Omega+ in heavy-ion collisions. In minimum-bias Au+Au collisions at square root s(NN)=200 GeV, a significant amount flow, comparable to other nonstrange baryons, is observed for which are expected be particularly sensitive dynamics partonic stage The pT dependence v2 confirms number constituent quark scaling previously lighter hadrons. These results support idea that substantial fraction...
We report precision measurements of the Feynman x (xF) dependence, and first transverse momentum (pT) single-spin asymmetries for production π0 mesons from polarized proton collisions at s=200 GeV. The xF dependence results is in fair agreement with perturbative QCD model calculations that identify orbital motion quarks gluons within as origin spin effects. Results pT fixed are not consistent these same QCD-based calculations.Received 21 January...
Direct photons produced in relativistic heavy-ion collisions allow access to the state of matter during collision, because they do not experience strong interaction and can escape from fireball without scattering. New data PHENIX experiment at RHIC show that as a function impact parameter yield direct increases much more rapidly than particle production, which provides new evidence for emission system when it was most hot dense.
The system created in noncentral relativistic nucleus-nucleus collisions possesses large orbital angular momentum. Because of spin-orbit coupling, particles produced such a could become globally polarized along the direction We present results \ensuremath{\Lambda} and $\overline{\ensuremath{\Lambda}}$ hyperon global polarization measurements Au+Au at $\sqrt{{s}_{\mathit{NN}}}=62.4$ 200 GeV performed with STAR detector BNL Relativistic Heavy Ion Collider (RHIC). observed hyperons acceptance...