M. L. Brooks
A5014251331- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Quantum Chromodynamics and Particle Interactions
- Particle Detector Development and Performance
- Nuclear reactor physics and engineering
- Dark Matter and Cosmic Phenomena
- Neutrino Physics Research
- Nuclear physics research studies
- CCD and CMOS Imaging Sensors
- Particle Accelerators and Free-Electron Lasers
- Radiation Detection and Scintillator Technologies
- Superconducting Materials and Applications
- Nuclear Physics and Applications
- Stochastic processes and statistical mechanics
- Radioactive Decay and Measurement Techniques
- Medical Imaging Techniques and Applications
- Markov Chains and Monte Carlo Methods
- Atomic and Subatomic Physics Research
- Laser Design and Applications
- Advancements in Semiconductor Devices and Circuit Design
- Cosmology and Gravitation Theories
- Plasma Diagnostics and Applications
- Calibration and Measurement Techniques
- Computational Physics and Python Applications
- Scientific Research and Discoveries
Los Alamos National Laboratory
2016-2025
Banaras Hindu University
2007-2023
Bhabha Atomic Research Centre
2018-2023
Charles University
2023
Augustana University
2018-2023
Duquesne University
2023
Weizmann Institute of Science
2022
Japan Atomic Energy Agency
2016
Laboratoire Leprince-Ringuet
2011
École Polytechnique
2011
Transverse momentum spectra for charged hadrons and neutral pions in the range 1 GeV/c<p(T)<5 GeV/c have been measured by PHENIX experiment at RHIC Au+Au collisions root square[s(NN)] = 130 GeV. At high p(T) from peripheral nuclear are consistent with scaling p+p average number of binary nucleon-nucleon collisions. The central significantly suppressed when compared to binary-scaled expectation, also similarly collisions, indicating a novel nuclear-medium effect energies.
The centrality dependence of transverse momentum distributions and yields for ${\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}},{K}^{\ifmmode\pm\else\textpm\fi{}},p$, $\overline{p}$ in $\text{Au}+\text{Au}$ collisions at $\sqrt{{s}_{NN}}=200\phantom{\rule{0.3em}{0ex}}\text{GeV}$ midrapidity are measured by the PHENIX experiment Relativistic Heavy Ion Collider. We observe a clear particle mass shapes spectra central below $\ensuremath{\sim}2\phantom{\rule{0.3em}{0ex}}\text{GeV}∕c$ ${p}_{T}$....
The anisotropy parameter (v(2)), the second harmonic of azimuthal particle distribution, has been measured with PHENIX detector in Au+Au collisions at sqrt[s(NN)]=200 GeV for identified and inclusive charged production central rapidities (|eta|<0.35) respect to reaction plane defined high (|eta|=3-4 ). We observe that v(2) mesons falls below (anti)baryons p(T)>2 GeV/c, marked contrast predictions a hydrodynamical model. A quark-coalescence model is also investigated.
Transverse momentum spectra of neutral pions in the range 1<pT<10 GeV/c have been measured at midrapidity by PHENIX experiment BNL RHIC Au+Au collisions sNN=200 GeV. The π0 multiplicity central reactions is significantly below yields same sNN peripheral and p+p scaled number nucleon-nucleon collisions. For most bin, suppression factor ∼2.5 pT=2 increases to ∼4–5 pT≈4 GeV/c. At larger pT, remains constant within errors. deficit already apparent semiperipheral smoothly with centrality.Received...
The PHENIX experiment at the BNL Relativistic Heavy Ion Collider (RHIC) has measured electrons with $0.3<{p}_{T}<9\text{ }\text{ }\mathrm{GeV}/c$ midrapidity ($|y|<0.35$) from heavy-flavor (charm and bottom) decays in $\mathrm{Au}+\mathrm{Au}$ collisions $\sqrt{{s}_{\mathrm{NN}}}=200\text{ }\mathrm{GeV}$. nuclear modification factor ${R}_{\mathrm{AA}}$ relative to $p+p$ shows a strong suppression central collisions, indicating substantial energy loss of heavy quarks medium produced RHIC...
An experiment has been performed to search for the muon- and electron-number nonconserving decay μ+→e+γ. The upper limit branching ratio is found be Γ(μ+→e+γ)/ Γ(μ+→e+ν¯ν)<1.2×10−11 with 90% confidence.Received 10 May 1999DOI:https://doi.org/10.1103/PhysRevLett.83.1521©1999 American Physical Society
Measurements of the ratio Drell-Yan yields from an 800 \rm{GeV/c} proton beam incident on liquid hydrogen and deuterium targets are reported. Approximately 360,000 muon pairs remained after all cuts data. From these data, anti-down ($\bar{d}$) to anti-up ($\bar{u}$) quark distributions in sea is determined over a wide range Bjorken-$x$. These results confirm previous measurements by E866 extend them lower $x$. $(\bar{d}-\bar{u})$ $\int(\bar{d}-\bar{u})dx$ evaluated for $0.015<x<0.35$....
Transverse momentum spectra of charged hadrons with p(T)<8 GeV/c and neutral pions p(T)<10 have been measured at midrapidity by the PHENIX experiment BNL RHIC in d+Au collisions sqrt[s(NN)]=200 GeV. The yields are compared to those p+p same sqrt[s(NN)] scaled up number underlying nucleon-nucleon d+Au. yield ratio does not show suppression observed central Au+Au RHIC. Instead, there is a small enhancement high particles.
The production of low mass e+e- pairs for m_{e+e-} < 300 MeV/c^2 and 1 p_T <5 GeV/c is measured in p+p Au+Au collisions at sqrt(s_NN)=200 GeV. Enhanced yield above hadronic sources observed. Treating the excess as internal conversions, invariant direct photons deduced. In central collisions, photon over exponential transverse momentum, with inverse slope T = 221 +/- 19 (stat) (syst) MeV. Hydrodynamical models initial temperatures ranging from 300--600 MeV times ~ 0.6 - 0.15 fm/c after...
The PHENIX experiment at the BNL Relativistic Heavy Ion Collider (RHIC)has measured $J/\ensuremath{\psi}$ production for rapidities $\ensuremath{-}2.2<y<2.2$ in $\mathrm{Au}+\mathrm{Au}$ collisions $\sqrt{{s}_{NN}}=200\text{ }\text{ }\mathrm{GeV}$. invariant yield and nuclear modification factor ${R}_{AA}$ as a function of centrality,transverse momentum, rapidity are reported. A suppression relative to binary collision scaling proton-protonreaction yields is observed. Models which describe...
Differential measurements of elliptic flow (${v}_{2}$) for $\mathrm{Au}+\mathrm{Au}$ and $\mathrm{Cu}+\mathrm{Cu}$ collisions at $\sqrt{{s}_{\mathrm{NN}}}=200\text{ }\text{ }\mathrm{GeV}$ are used to test validate predictions from perfect fluid hydrodynamics scaling ${v}_{2}$ with eccentricity, system size, transverse kinetic energy (${\mathrm{KE}}_{T}$). For ${\mathrm{KE}}_{T}\ensuremath{\equiv}{m}_{T}\ensuremath{-}m$ up $\ensuremath{\sim}1\text{ the is compatible hydrodynamic expansion a...
Flow coefficients v_n for n = 2, 3, 4, characterizing the anisotropic collective flow in Au+Au collisions at sqrt(s_NN) 200 GeV, are measured relative to event planes \Psi_n determined large rapidity. We report as a function of transverse momentum and collision centrality, study correlations among different order n. The well described by hydrodynamic models which employ Glauber Monte Carlo initial state geometry with fluctuations, providing additional constraining power on interplay between...
Azimuthal angle ($\ensuremath{\Delta}\ensuremath{\phi}$) correlations are presented for a broad range of transverse momentum ($0.4<{p}_{T}<10$ GeV/$c$) and centrality (0--92%) selections charged hadrons from dijets in Au+Au collisions at $\sqrt{{s}_{\mathit{NN}}}=200$ GeV. With increasing ${p}_{T}$, the away-side $\ensuremath{\Delta}\ensuremath{\phi}$ distribution evolves relatively flat shape to concave shape, then convex shape. Comparisons with $p+p$ data suggest that can be divided into...
For Au + collisions at 200 GeV, we measure neutral pion production with good statistics for transverse momentum, pT, up to 20 GeV/c. A fivefold suppression is found, which essentially constant 5 < pT Experimental uncertainties are small enough constrain any model-dependent parametrization the transport coefficient of medium, e.g., q in parton quenching model. The spectral shape similar all collision classes, and does not saturate collisions.
PHENIX has measured the e^+e^- pair continuum in sqrt(s_NN)=200 GeV Au+Au and p+p collisions over a wide range of mass transverse momenta. The yield is compared to expectations from hadronic sources, based on measurements. In intermediate region, between masses phi J/psi meson, consistent with correlated c^bar-c production, though other mechanisms are not ruled out. low region (below phi) inclusive spectrum well described by known contributions light meson decays. contrast, minimum bias this...
The PHENIX collaboration at the Relativistic Heavy Ion Collider (RHIC) reports measurements of azimuthal dihadron correlations near midrapidity in $d$$+$Au collisions $\sqrt{s_{_{NN}}}$=200 GeV. These complement recent analyses by experiments Large Hadron (LHC) involving central $p$$+$Pb $\sqrt{s_{_{NN}}}$=5.02 TeV, which have indicated strong anisotropic long-range angular distributions hadron pairs. origin these anisotropies is currently unknown. Various competing explanations include...
Transverse momentum spectra of electrons (${p}_{T}^{e}$) from semileptonic weak decays heavy-flavor mesons in the range $0.3<{p}_{T}^{e}<9.0$ GeV/$c$ have been measured at midrapidity ($|y|<0.35$) by PHENIX experiment Relativistic Heavy Ion Collider $p+p$ and $\mathrm{Au}+\mathrm{Au}$ collisions $\sqrt{{s}_{\mathrm{NN}}}=200$ GeV. In addition, azimuthal anisotropy parameter ${v}_{2}$ has for $0.3<{p}_{T}^{e}<5.0$ collisions. The substantial modification ${p}_{T}^{e}$ compared with as well...
The PHENIX experiment at the Relativistic Heavy Ion Collider has measured invariant differential cross section for production of ${K}_{S}^{0}$, $\ensuremath{\omega}$, ${\ensuremath{\eta}}^{\ensuremath{'}}$, and $\ensuremath{\phi}$ mesons in $p+p$ collisions $\sqrt{s}=200\text{ }\text{ }\mathrm{GeV}$. Measurements $\ensuremath{\omega}$ different decay channels give consistent results. New results are agreement with previously published data extend ${p}_{T}$ coverage. spectral shapes all...
The second Fourier component ${v}_{2}$ of the azimuthal anisotropy with respect to reaction plane is measured for direct photons at midrapidity and transverse momentum (${p}_{T}$) $1--12\text{ }\text{ }\mathrm{GeV}/c$ in $\mathrm{Au}+\mathrm{Au}$ collisions $\sqrt{{s}_{NN}}=200\text{ }\mathrm{GeV}$. Previous measurements this quantity hadrons ${p}_{T}<6\text{ indicate that medium behaves like a nearly perfect fluid, while ${p}_{T}>6\text{ reduced interpreted terms path-length dependence...
The PHENIX experiment has measured midrapidity ([FORMULA: SEE TEXT]) transverse momentum spectra of electrons as a function centrality in Au+Au collisions at [FORMULA: TEXT]. Contributions from photon conversions and light hadron decays, mainly Dalitz decays pi0 eta mesons, were removed. resulting nonphotonic electron are primarily due to the semileptonic hadrons carrying heavy quarks. Nuclear modification factors determined by comparison p+p collisions. A significant suppression high pT is...
Azimuthal correlations of jet-induced high-pT charged hadron pairs are studied at midrapidity in Au+Au collisions √sNN=200 GeV. The distribution jet-associated partner hadrons (1.0<pT<2.5 GeV/c) per trigger (2.5<pT<4.0 is found to vary with collision centrality, both shape and yield, indicating a significant effect the nuclear medium on jet fragmentation process.Received 1 July 2005DOI:https://doi.org/10.1103/PhysRevLett.97.052301©2006 American Physical Society
The PHENIX experiment at RHIC has measured charged hadron yields mid-rapidity over a wide range of transverse momentum (0.5 < p_T 10 GeV/c) in Au+Au collisions sqrt(s_NN)=200 GeV. data are compared to pi^zero measurements from the same experiment. For both hadrons and neutral pions, per nucleon-nucleon collision significantly suppressed central peripheral collisions. suppression sets gradually increases with increasing centrality Above 4-5 GeV/c p_T, constant almost identical pi^zeroes is...