Azimuthal anisotropy of direct photons in Au+Au collisions at βsNN=200GeV
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73 NUCLEAR PHYSICS AND RADIATION PHYSICSβ
Engineering topics
David, G.
Publications and source records attributed to David, G..
Erratum: Centrality-Dependent Modification of Jet-Production Rates in Deuteron-Gold Collisions at $\sqrt{π _{πβ’π}}$ = 200 GeV [Phys. Rev. Lett. 116, 122301 (2016)]
We previously reported jet-production rates in π + π and π + Au collisions at $\sqrt{π _{πβ’π}}$ = 200 GeV recorded in 2008 with the PHENIX detector at the Relativistic Heavy Ion Collider. Subsequently, we found that electronic noise in the electromagnetic calorimeter was not completely removed by the tower-timing cuts used in the analysis. We have conducted an independent re-analysis of the data that eliminated noisy towers by removing them completely from the analysis. These cuts remove any contributions from instrumental noise, but reduce the overall acceptance for electromagnetic clusters by β16% and hence the overall statistical power of the data. Finally, this re-analysis found that instrumental noise in the electromagnetic calorimeter led to an artificial increase in the jet yield for both the π + π and π + Au collisions.
73 NUCLEAR PHYSICS AND RADIATION PHYSICSβ
Design of the ECCE detector for the Electron Ion Collider
The EIC Comprehensive Chromodynamics Experiment (ECCE) detector has been designed to address the full scope of the proposed Electron Ion Collider (EIC) physics program as presented by the National Academy of Science and provide a deeper understanding of the quark-gluon structure of matter. To accomplish this, the ECCE detector offers nearly acceptance and energy coverage along with excellent tracking and particle identification. The ECCE detector was designed to be built within the budget envelope set out by the EIC project while simultaneously managing cost and schedule risks. Finally, this detector concept has been selected to be the basis for the EIC project detector.
47 OTHER INSTRUMENTATIONβ
Jet modification via π 0 -hadron correlations in Au + Au collisions at $\sqrt{s_{NN}}$ = 200 GeV
High-momentum two-particle correlations are a useful tool for studying jet-quenching effects in the quark-gluon plasma. Angular correlations between neutral-pion triggers and charged hadrons with transverse momenta in the range 4β12 GeV/π and 0.5β7 GeV/π, respectively, have been measured by the PHENIX experiment in 2014 for Au + Au collisions at $\sqrt{s_{NN}}$ = 200 GeV. Suppression is observed in the yield of high-momentum jet fragments opposite the trigger particle, which indicates jet suppression stemming from in-medium partonic energy loss, while enhancement is observed for low-momentum particles. The ratio and differences between the yield in Au + Au collisions and π + π collisions, πΌ π΄β’π΄ and Ξ π΄β’π΄ , as a function of the trigger-hadron azimuthal separation, Ξβ’π, are measured for the first time at the BNL Relativistic Heavy Ion Collider. Finally, these results better quantify how the yield of low-π π associated hadrons is enhanced at wide angle, which is crucial for studying energy loss as well as medium-response effects.
73 NUCLEAR PHYSICS AND RADIATION PHYSICSβ
Identified charged-hadron production in π+Al, 3 He + Au, and Cu + Au collisions at $\sqrt{s_{NN}}$ = 200 GeV and in U + U collisions at $\sqrt{s_{NN}}$ = 193 GeV
The PHENIX experiment has performed a systematic study of identified charged-hadron (π Β± , πΎ Β± , π, $\bar{π}$) production at midrapidity in π + Al, 3 He + Au, and Cu + Au collisions at $\sqrt{s_{NN}}$ = 200 GeV and U + U collisions at $\sqrt{s_{NN}}$ = 193 GeV. Identified charged-hadron invariant transverse-momentum (π π ) and transverse-mass (π π ) spectra are presented and interpreted in terms of radially expanding thermalized systems. The particle ratios of πΎ/π and π/π have been measured in different centrality ranges of large (Cu + Au and U + U) and small (π + Al and 3 He + Au) collision systems. The values of πΎ/π ratios measured in all considered collision systems were found to be consistent with those measured in π+π collisions. However, the values of π/π ratios measured in large collision systems reach the values of β0.6, which is a factor of β2 larger than in π + π collisions. These results can be qualitatively understood in terms of the baryon enhancement expected from hadronization by recombination. Identified charged-hadron nuclear-modification factors (π π΄β’π΅ ) are also presented. Enhancement of proton π π΄β’π΅ values over meson π π΄β’π΅ values was observed in central 3 He + Au, Cu + Au, and U + U collisions. Finally, the proton π π΄β’π΅ values measured in the π + Al collision system were found to be consistent with π π΄β’π΅ values of π, π Β± , πΎ Β± , and π 0 mesons, which may indicate that the size of the system produced in π + Al collisions is too small for recombination to cause a noticeable increase in proton production.
73 NUCLEAR PHYSICS AND RADIATION PHYSICSβ
Nonprompt direct-photon production in Au + Au collisions at $\sqrt{s_{NN}}$ = 200 GeV
The measurement of the direct-photon spectrum from Au + Au collisions at $\sqrt{s_{NN}}$ = 200 GeV is presented by the PHENIX Collaboration using the external-photon-conversion technique for 0%β93% central collisions in a transverse-momentum (π π ) range of 0.8β10 GeV/π. An excess of direct photons, above prompt-photon production from hard-scattering processes, is observed for π π < 6 GeV/π. Nonprompt direct photons are measured by subtracting the prompt component, which is estimated as π coll -scaled direct photons from π + π collisions at 200 GeV, from the direct-photon spectrum. Results are obtained for 0.8 < π π < 6.0 GeV/π and suggest that the spectrum has an increasing inverse slope from β0.2 to 0.4 GeV/π with increasing π π , which indicates a possible sensitivity of the measurement to photons from earlier stages of the evolution of the collision. In addition, like the direct-photon production, the π π -integrated nonprompt direct-photon yields also follow a power-law scaling behavior as a function of collision-system size. Finally, the exponent, πΌ, for the nonprompt component is found to be consistent with 1.1 with no apparent π π dependence.
73 NUCLEAR PHYSICS AND RADIATION PHYSICSβ
Charm- and bottom-quark production in Au+Au collisions at $$ \sqrt{{\textrm{s}}_{\textrm{NN}}} $$=200 GeV
Here, the invariant yield of electrons from open-heavy-flavor decays for 1 < p T < 8 GeV/c at midrapidity |y| < 0.35 in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV has been measured by the PHENIX experiment at the Relativistic Heavy Ion Collider. A displaced-vertex analysis with the PHENIX silicon-vertex detector enables extraction of the fraction of charm and bottom hadron decays and unfolding of the invariant yield of parent charm and bottom hadrons. The nuclear-modification factors RAA for electrons from charm and bottom hadron decays and heavy-flavor hadrons show both a centrality and a quark-mass dependence, indicating suppression in the quark-gluon plasma produced in these collisions that is medium sized and quark-mass dependent.
73 NUCLEAR PHYSICS AND RADIATION PHYSICSβ
Transverse single-spin asymmetry of charged hadrons at forward and backward rapidity in polarized p + p , p + Al , and p + Au collisions at s N N = 200 GeV
Not Available
73 NUCLEAR PHYSICS AND RADIATION PHYSICSβ
Erratum: LΓ©vy-stable two-pion Bose-Einstein correlations in s N N = 200 GeV Au + Au collisions [Phys. Rev. C 97 , 064911 (2018)]
We previously published in 2018 a detailed measurement recorded in 2010 for Au+Au collisions at $\sqrt{^SNN}$ = 200 GeV of charged two-pion correlation functions in 0%-30% centrality. We found the data to be well described by Bose-Einstein correlation functions stemming from L$\acute{e}$vy-stable source distributions. Using a fine transverse momentum binning, we extracted the correlation strength parameter Ξ», the L$\acute{e}$vy index of stability Ξ± and the L$\acute{e}$vy length scale parameter R as a function of average transverse mass of the pair m T .
73 NUCLEAR PHYSICS AND RADIATION PHYSICSβ
Data preservation in high energy physics
Data preservation is a mandatory specification for any present and future experimental facility and it is a cost-effective way of doing fundamental research by exploiting unique data sets in the light of the continuously increasing theoretical understanding. This document summarizes the status of data preservation in high energy physics. The paradigms and the methodological advances are discussed from a perspective of more than ten years of experience with a structured effort at international level. The status and the scientific return related to the preservation of data accumulated at large collider experiments are presented, together with an account of ongoing efforts to ensure long-term analysis capabilities for ongoing and future experiments. Transverse projects aimed at generic solutions, most of which are specifically inspired by open science and FAIR principles, are presented as well. A prospective and an action plan are also indicated.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDSβ
Evaluation of longitudinal double-spin asymmetry measurements in semi-inclusive deep-inelastic scattering from the proton for the ECCE detector design
The evaluation of the measurement of double-spin asymmetries for charge-separated pions and kaons produced in deep-inelastic scattering from the proton using the ECCE detector design concept is presented, for the combinations of lepton and hadron beam energies of 5 Γ 41 GeV 2 and 18 Γ 275 GeV 2 . The study uses unpolarised simulated data that are processed through a full GEANT simulation of the detector. These data are then reweighted at the parton level with DSSV helicity distributions and DSS fragmentation functions, in order to generate the relevant asymmetries, and subsequently analysed. Furthermore, the performed analysis shows that the ECCE detector concept provides the resolution and acceptance, with a broad coverage in kinematic phase space, needed for a robust extraction of asymmetries. This, in turn, allows for a precise extraction of sea-quark helicity distributions.
73 NUCLEAR PHYSICS AND RADIATION PHYSICSβ
Design and simulated performance of calorimetry systems for the ECCE detector at the electron ion collider
Here, we describe the design and performance the calorimeter systems used in the ECCE detector to achieve the overall performance specifications cost-effectively with careful consideration of appropriate technical and schedule risks. The calorimeter systems consist of three electromagnetic calorimeters, covering the combined pseudorapidity range from -3.7 to 3.8 and two hadronic calorimeters covering a combined range of -1.1<Ξ·<3.8. Key calorimeter performances which include energy and position resolutions, reconstruction efficiency, and particle identification will be presented.
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND β
ECCE unpolarized TMD measurements
For this work, we performed feasibility studies for various measurements that are related to unpolarized TMD distribution and fragmentation functions for the ECCE detector proposal. The processes studied include semi-inclusive Deep inelastic scattering (SIDIS) where single hadrons (pions and kaons) were detected in addition to the scattered DIS lepton. The single hadron cross sections and multiplicities were extracted as a function of the DIS variables x and Q 2 , as well as the semi-inclusive variables z, which corresponds to the momentum fraction the detected hadron carries relative to the struck parton and P T , which corresponds to the transverse momentum of the detected hadron relative to the virtual photon. The expected statistical precision of such measurements is extrapolated to accumulated luminosities of 10 fb β1 and potential systematic uncertainties are approximated given the deviations between true and reconstructed yields. The expected uncertainties are then used to obtain the expected impact on the related TMD distribution and fragmentation functions. We find that the ECCE detector proposal fulfills the physics requirements on these channels as detailed in the EIC Yellow Report.
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND β
Measurement of Direct-Photon Cross Section and Double-Helicity Asymmetry at s = 510 GeV in p β + p β Collisions
Not Available
73 NUCLEAR PHYSICS AND RADIATION PHYSICSβ
Transverse single-spin asymmetry of midrapidity Ο 0 and Ξ· mesons in p + Au and p + Al collisions at s N N = 200 GeV
Not Available
73 NUCLEAR PHYSICS AND RADIATION PHYSICSβ
Search for e β Ο charged lepton flavor violation at the EIC with the ECCE detector
The recently approved Electron-Ion Collider (EIC) will provide a unique new opportunity for searches of charged lepton flavor violation (CLFV) and other new physics scenarios. In contrast to the e β ΞΌ CLFV transition for which very stringent limits exist, there is still a relatively large discovery space for the e β Ο CLFV transition, potentially to be explored by the EIC. Here, with the latest detector design of ECCE (EIC Comprehensive Chromodynamics Experiment) and projected integral luminosity of the EIC, we find the Ο-leptons created in the DIS process ep β ΟX are expected to be identified with high efficiency. A first ECCE simulation study, restricted to the 3-prong Ο-decay mode and with limited statistics for the Standard Model backgrounds, estimates that the EIC will be able to improve the current exclusion limit on e β Ο CLFV by an order of magnitude. As a result, the very high vertex resolution of the ECCE detector configuration plays a critical role in Ο identification.
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND β
Detector requirements and simulation results for the EIC exclusive, diffractive and tagging physics program using the ECCE detector concept
This article presents a collection of simulation studies using the ECCE detector concept in the context of the EICβs exclusive, diffractive, and tagging physics program, which aims to further explore the rich quarkβgluon structure of nucleons and nuclei. To successfully execute the program, ECCE proposed to utilize the detector system close to the beamline to ensure exclusivity and tag ion beam/fragments for a particular reaction of interest. Preliminary studies confirm the proposed technology and design satisfy the requirements. Further, the projected physics impact results are based on the projected detector performance from the simulation at 10 or 100 fb -1 of integrated luminosity. Additionally, insights related to a potential second EIC detector are documented, which could serve as a guidepost for future development.
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND β
Improving constraints on gluon spin-momentum correlations in transversely polarized protons via midrapidity open-heavy-flavor electrons in p β + p collisions at s = 200 GeV
Not Available
73 NUCLEAR PHYSICS AND RADIATION PHYSICSβ