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Measurements of semi-inclusive deep-inelastic scattering multiplicities for ${\pi }^{+}$ and ${\pi }^{-}$ from proton and deuteron targets are reported on a grid of hadron kinematic variables $z, P_T$ , and ${\varphi }^{*}$ for leptonic kinematic variables in the range $0.3<x<0.6$ and $3<Q^2<5{\mathrm{GeV}}^2$ . Data were acquired in 2018 and 2019 at Jefferson Lab Hall C with a 10.6 GeV electron beam impinging on 10-cm-long liquid hydrogen and deuterium targets. Scattered electrons and charged pions were detected in the High Momentum Spectrometer and Super High Momentum Spectrometer, respectively. The multiplicities were fitted for each bin in $(x,Q^2,z,P_t)$ to extract the ${\varphi }^{*}$ —independent $M_0$ and the azimuthal modulations $\langle cos\left({\varphi }^{*}\right)\rangle$ and $\langle cos\left(2{\varphi }^{*}\right)\rangle$ . The $P_t$ dependence of the $M_0$ results was found to be remarkably consistent for the four cases studied: $ep\to e{\pi }^{+}X, ep\to e{\pi }^{-}X, ed\to e{\pi }^{+}X, ed\to e{\pi }^{-}X$ over the range $0\text{GeV}<P_t<0.4\text{GeV}$ , as were the multiplicities evaluated near ${\varphi }^{*}={180}^{\circ }$ over the extended range $0\text{GeV}<P_t<0.7\text{GeV}$ . The Gaussian widths of the $P_t$ dependence exhibit a quadratic increase with $z$ . The $cos\left({\varphi }^{*}\right)$ modulations were found to be consistent with zero for ${\pi }^{+}$ , in agreement with previous world data, while the ${\pi }^{-}$ moments were, in many cases, significantly greater than zero. The $cos\left(2{\varphi }^{*}\right)$ modulations were found to be consistent with zero. The higher statistical precision of this dataset of about 20 000 individual multiplicity values, compared with previously published data, should allow improved determinations of quark transverse momentum distributions and higher twist contributions. 

Naturalistic team based speech communications requires specific protocols/procedures to be followed to allow for effective task completion for distributed team members. NASA Apollo-11 was the first manned space mission to successfully bring astronauts to the moon and return them safely. Mission specialists roles within NASA Mission Control (MOCR) are complex and reflected in their communications. In this study, we perform speaker clustering to identify speech segments uttered by the same speaker from recently recovered Fearless Steps APOLLO corpus (CRSS-UTDallas). We propose a pretrained network to obtain speaker embeddings and use a framework that builds on these learned embeddings which achieves a clustering accuracy of 73.4%. We also track/tag key speakers-of-interest across three critical mission phases and analyze speaker roles based on speech duration. NASA communication protocols dictate that information be communicated in a concise manner. In automated communication analysis, individuals higher in trait dominance generally speak more and gain more control over group processes. Hence, speaker duration of primary- versus -secondary speaker and speaker turns are metrics used to determine speaker role. This analysis provides greater understanding of communications protocol and serves as a lasting tribute to the «Heroes Behind the Heroes of Apollo» as well as preserve “words spoken in space.” 

We present results from the Jefferson Lab E08-014 experiment, investigating short-range correlations (SRC) through measurements of inclusive quasi-elastic scattering from 2H, 3He, 4He, 12C, 40Ca, and 48Ca. The kinematics were selected to isolate scattering from SRCs, yielding a plateau in the A/2H cross-section ratios due to the universal two-body structure of the 2N-SRCs in light and heavy nuclei. We observe approximate plateaus in the A/2H ratios and provide the first extractions of the A/2H ratio for 40Ca and 48Ca. We also examine the A/3He ratio, aiming to identify three-nucleon SRCs (3N-SRCs). Following the approach for isolating 2N-SRCs, searching for 3N-SRC dominance involved measuring the A/3He cross section ratio at modest-to-large 𝑄2 values and looking for a plateau ratios for 𝑥>∼2.5. This was not observed in the data, and in fact increasing 𝑄2 values moved the data further away from the predicted plateau. We show here that, when analyzed in terms of the struck nucleon’s light-cone momentum, the data exhibited the expected trend, progressively approaching the predicted 3N-SRC plateau. These observations suggest that future measurements at higher energies may facilitate a definitive isolation and identification of 3N-SRCs. 

The ability to assess conversational interactions creates a challenge in assessing speaker turns over time, including frequency of occurrence, duration of each turn, and connecting speakers in a multispeaker context. This is of particular interest in the analysis of teacher-student or adult-child interactions in learning spaces. The creation of a visualization mechanism capable of providing a high-level representation of the overall conversational interactions without overburdening educators in reviewing student/child learning engagement would be of great significance. Chord diagrams can visualize such complex and disparate information in compact form. In this study, we explore the creation of ‘Chord Diagrams’ as a way to analyze talk time between a child and adult speakers in learning spaces. The proposed illustration provides an opportunity to study the variations in speech duration and the interaction among speakers that are involved in the communication with each other over a certain time learning duration. 

Nucleon structure functions, as measured in lepton-nucleon scattering, have historically provided a critical observable in the study of partonic dynamics within the nucleon. However, at very large parton momenta, it is both experimentally and theoretically challenging to extract parton distributions due to the probable onset of nonperturbative contributions and the unavailability of high-precision data at critical kinematics. Extraction of the neutron structure and the d quark distribution have been further challenging because of the necessity of applying nuclear corrections when utilizing scattering data from a deuteron target to extract the free neutron structure. However, a program of experiments has been carried out recently at the energy-upgraded Jefferson Lab electron accelerator aimed at significantly reducing the nuclear correction uncertainties on the d quark distribution function at large partonic momentum. This allows leveraging the vast body of deuterium data covering a large kinematic range to be utilized for d quark parton distribution function extraction. In this Letter, we present new data from experiment E12-10-002, carried out in Jefferson Lab Experimental Hall C, on the deuteron to proton cross section ratio at large Bjorken $x$ . These results significantly improve the precision of existing data and provide a first look at the expected impact on quark distributions extracted from parton distribution function fits. 

Abstract Quantum Chromodynamics predicts a phase transition from hadronic matter to quark–gluon plasma (QGP) at high temperatures and energy densities, where quarks and gluons (partons) are no longer confined within hadrons. The QGP forms in ultrarelativistic heavy-ion collisions. Anisotropic flow coefficients, quantifying the azimuthal expansion of produced matter, probe QGP properties. Flow measurements in high-energy heavy-ion collisions show a distinctive grouping of anisotropic flow for baryons and mesons at intermediate transverse momentum – a feature associated with flow imparted at the quark level, confirming QGP existence. The observation of QGP-like features in proton–proton and proton–ion collisions has sparked debate about QGP formation in smaller systems. For the first time, we demonstrate the distinctive grouping of anisotropic flow for baryons and mesons in high-multiplicity proton–lead and proton–proton collisions at the Large Hadron Collider (LHC). These results are described by a model including hydrodynamic flow followed by hadron formation via quark coalescence, consistent with the formation of partonic flowing systems in these collisions. 

ABSTRACT Accurate stellar parameters of stars in open clusters can help constrain models of stellar structure and evolution. Here, we wish to determine the age and metallicity content of the open cluster NGC 2506. To this end, we investigated three detached eclipsing binaries (DEBs; V2032, V4, and V5) for which we determined their masses and radii, as well as four red giant branch stars for which we determined their effective temperatures, surface gravities, and metallicities. Three of the stars in the DEBs have masses close to the cluster turn-off mass, allowing for extremely precise age determination. Comparing the values for the masses and radii of the binaries to BaSTI (a Bag of Stellar Tracks and Isochrones) isochrones, we estimated a cluster age of 2.01 ± 0.10 Gyr. This does depend on the models used in the comparison, where we have found that the inclusion of convective core-overshooting is necessary to properly model the cluster. From red giant branch stars, we determined values for the effective temperatures, the surface gravities, and the metallicities. From these we find a cluster metallicity of −0.36 ± 0.10 dex. Using this value and the values for the effective temperatures, we determine the reddening to be E(b − y) = 0.057 ± 0.004 mag. Furthermore, we derived the distance to the cluster from Gaia parallaxes and found 3.101 ± 0.017 kpc, and we have performed a radial velocity membership determination for stars in the field of the cluster. Finally, we report on the detection of oscillation signals in γ Dor and δ Scuti members in data from the Transiting Exoplanet Survey Satellite (TESS) mission, including the possible detection of solar-like oscillations in two of the red giants.