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Abstract The pseudorapidity distribution of charged hadrons produced in Au+Au collisions at a center-of-mass energy of s NN$$ \\sqrt{{\\textrm{s}}_{\\textrm{NN}}} $$= 200 GeV is measured using data collected by the sPHENIX detector. Charged hadron yields are extracted by counting cluster pairs in the inner and outer layers of the Intermediate Silicon Tracker, with corrections applied for detector acceptance, reconstruction efficiency, combinatorial pairs, and contributions from secondary decays. The measured distributions cover |η| < 1.1 across various centralities, and the average pseudorapidity density of charged hadrons at mid-rapidity is compared to predictions from Monte Carlo heavy-ion event generators. This result, featuring full azimuthal coverage at mid-rapidity, is consistent with previous experimental measurements at the Relativistic Heavy Ion Collider, thereby supporting the broader sPHENIX physics program.

(ProQuest: ... denotes formulae and/or non-USASCII text omitted; see image).A search for ... decays is performed using 3.0 fb super(1-) of pp collision data recorded by the LHCb experiment during 2011 and 2012. The f sub(0)(980) meson is reconstructed through its decay to the pi super(+) pi super(-) final state in the mass window 900 MeV/c super(2) < m( pi super(+) pi super(-)) < 1080 MeV/c super(2). No significant signal is observed. The first upper limits on the branching fraction of ... are set at 90 % (95 %) confidence level. [Figure not available: see fulltext.]

Precise knowledge of the location of the material in the LHCb vertex locator (VELO) is essential to reducing background in searches for long-lived exotic particles, and in identifying jets that originate from beauty and charm quarks. Secondary interactions of hadrons produced in beam-gas collisions are used to map the location of material in the VELO. Using this material map, along with properties of a reconstructed secondary vertex and its constituent tracks, a \\(p\\)-value can be assigned to the hypothesis that the secondary vertex originates from a material interaction. A validation of this procedure is presented using photon conversions to dimuons.

Abstract Two new algorithms for use in the analysis of$$pp$$p p collision are developed to identify the flavour of$${\\mathrm {B}} ^0$$B 0 mesons at production using pions and protons from the hadronization process. The algorithms are optimized and calibrated on data, using$${{\\mathrm {B}} ^0} \\!\\rightarrow D^{-}\\pi ^{+}$$B 0 → D - π + decays from$$pp$$p p collision data collected by LHCb at centre-of-mass energies of 7 and 8 TeV . The tagging power of the new pion algorithm is 60% greater than the previously available one; the algorithm using protons to identify the flavour of a$${\\mathrm {B}} ^0$$B 0 meson is the first of its kind.

This article presents a collection of simulation studies using the ECCE detector concept in the context of the EIC's exclusive, diffractive, and tagging physics program, which aims to further explore the rich quark-gluon structure of nucleons and nuclei. To successfully execute the program, ECCE proposed to utilize the detecter system close to the beamline to ensure exclusivity and tag ion beam/fragments for a particular reaction of interest. Preliminary studies confirmed the proposed technology and design satisfy the requirements. 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, a few insights on the potential 2nd Interaction Region can (IR) were also documented which could serve as a guidepost for the future development of a second EIC detector.

The pseudorapidity distribution of charged hadrons produced in Au+Au collisions at a center-of-mass energy of \\(\\sqrt{s_\\mathrm{NN}} = 200\\) GeV is measured using data collected by the sPHENIX detector. Charged hadron yields are extracted by counting cluster pairs in the inner and outer layers of the Intermediate Silicon Tracker, with corrections applied for detector acceptance, reconstruction efficiency, combinatorial pairs, and contributions from secondary decays. The measured distributions cover \\(|\\eta| < 1.1\\) across various centralities, and the average pseudorapidity density of charged hadrons at mid-rapidity is compared to predictions from Monte Carlo heavy-ion event generators. This result, featuring full azimuthal coverage at mid-rapidity, is consistent with previous experimental measurements at the Relativistic Heavy Ion Collider, thereby supporting the broader sPHENIX physics program.

This paper reports measurements of the transverse energy per unit pseudorapidity (\\(dE_{T}/d\\eta\\)) produced in Au+Au collisions at \\(\\sqrt{s_{NN}} = 200\\) GeV, performed with the sPHENIX detector at the Relativistic Heavy Ion Collider (RHIC). The results cover the pseudorapidity range \\(\\left|\\eta\\right| < 1.1\\) and constitute the first such measurement performed using a hadronic calorimeter at RHIC. Measurements of \\(dE_{T}/d\\eta\\) are presented for a range of centrality intervals and the average \\(dE_{T}/d\\eta\\) as a function of the number of participating nucleons, \\(N_{\\mathrm{part}}\\), is compared to a variety of Monte Carlo heavy-ion event generators. The results are in agreement with previous measurements at RHIC, and feature an improved granularity in \\(\\eta\\) and improved precision in low-\\(N_{\\mathrm{part}}\\) events.

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. This detector concept has been selected to be the basis for the EIC project detector.

PHENIX presents a simultaneous measurement of the production of direct \\(\\) and \\(^0\\) in$d$ $+\\(Au collisions at \\)\\sqrt{s_{_{NN}}}=200\\( GeV over a \\)p_T\\( range of 7.5 to 18 GeV/\\)c\\( for different event samples selected by event activity, i.e. charged-particle multiplicity detected at forward rapidity. Direct-photon yields are used to empirically estimate the contribution of hard-scattering processes in the different event samples. Using this estimate, the average nuclear-modification factor \\)R_{d\\rm Au,EXP}^{\\gamma^{\\rm dir}}\\( is \\)0.925{\\pm}0.023({\\rm stat}){\\pm}0.15^{\\rm (scale)}\\(, consistent with unity for minimum-bias (MB) \\)d$ $+\\(Au events. For event classes with moderate event activity, \\)R_{d\\rm Au,EXP}^{\\gamma^{\\rm dir}}\\( is consistent with the MB value within 5\\% uncertainty. These results confirm that the previously observed enhancement of high-\\)p_T\\( \\)\\pi^0\\( production found in small-system collisions with low event activity is a result of a bias in interpreting event activity within the Glauber framework. In contrast, for the top 5\\% of events with the highest event activity, \\)R_{d\\rm Au,EXP}^{\\gamma^{\\rm dir}}\\( is suppressed by 20\\% relative to the MB value with a significance of \\)4.5\\sigma$ , which may be due to final-state effects.

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\\%--93\\% central collisions in a transverse-momentum (\\(p_T\\)) range of 0.8--10 GeV/\\(c\\). An excess of direct photons, above prompt-photon production from hard-scattering processes, is observed for \\(p_T<6\\) GeV/\\(c\\). Nonprompt direct photons are measured by subtracting the prompt component, which is estimated as \\(N_{\\rm coll}\\)-scaled direct photons from $p$$+$$p\\( collisions at 200 GeV, from the direct-photon spectrum. Results are obtained for \\)0.8

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