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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. 

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.” 

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. 

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. 

Context. Models of stellar structure and evolution can be constrained using accurate measurements of the parameters of eclipsing binary members of open clusters. Multiple binary stars provide the means to tighten the constraints and, in turn, to improve the precision and accuracy of the age estimate of the host cluster. In the previous two papers of this series, we have demonstrated the use of measurements of multiple eclipsing binaries in the old open cluster NGC 6791 to set tighter constraints on the properties of stellar models than was previously possible, thereby improving both the accuracy and precision of the cluster age. Aims. We identify and measure the properties of a non-eclipsing cluster member, V56, in NGC 6791 and demonstrate how this provides additional model constraints that support and strengthen our previous findings. Methods. We analyse multi-epoch spectra of V56 from FLAMES in conjunction with the existing photometry and measurements of eclipsing binaries in NGC6971. Results. The parameters of the V56 components are found to be M p  = 1.103 ± 0.008  M ⊙ and M s  = 0.974 ± 0.007  M ⊙ , R p  = 1.764 ± 0.099  R ⊙ and R s  = 1.045 ± 0.057  R ⊙ , T eff,p  = 5447 ± 125 K and T eff,s  = 5552 ± 125 K, and surface [Fe/H] = +0.29 ± 0.06 assuming that they have the same abundance. Conclusions. The derived properties strengthen our previous best estimate of the cluster age of 8.3 ± 0.3 Gyr and the mass of stars on the lower red giant branch (RGB), which is M RGB  = 1.15 ± 0.02  M ⊙ for NGC 6791. These numbers therefore continue to serve as verification points for other methods of age and mass measures, such as asteroseismology.