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Generalized parton distributions and exclusive processes

In last fifteen years, GPDs have emerged as a powerful tool to reveal such aspects of the QCD structure of the nucleon as: - 3D parton correlations and distributions; - spin content of the nucleon. Further advances in the field of GPDs and hard exclusive processes rely on: - developments in theory and new methods in phenomenology such as new flexible parameterizations, neural networks, global QCD fits - new high-precision data covering unexplored kinematics: JLab at 6 and 12 GeV, Hermes with recoil detector, Compass, EIC. This slide-show presents: Nucleon structure in QCD, particularly hard processes, factorization and parton distributions; and a brief overview of GPD phenomenology, including basic properties of GPDs, GPDs and QCD structure of the nucleon, and constraining GPDs from experiments.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Spin Orbit Correlations and the Structure of the Nucleon

Extensive experimental measurements of spin and azimuthal asymmetries in various processes have stimulated theoretical interest and progress in the studies of the nucleon structure. The interpretation of experimental data in terms of parton distribution functions, generalized to describe transverse momentum and spatial parton distributions, is one of the main remaining challenges of modern nuclear physics. These new parton distribution and fragmentation functions encode the motion and the position of partons and are often referred to as three-dimensional distributions describing the three-dimensional (3D) structure of the nucleon. Understanding of the production mechanism and performing phenomenological studies compatible with factorization theorems using minimal model assumptions are goals of the analysis of the experimental data. HERMES and COMPASS Collaborations and experiments at Jefferson Lab have collected a wealth of polarized and unpolarized Semi-Inclusive Deep Inelastic Scattering (SIDIS) data. These data play a crucial role in current understanding of nucleon spin phenomena as they cover a broad kinematical range. The Jefferson Lab 12 GeV upgrade data on polarized and unpolarized SIDIS will have a remarkably higher precision at large parton fractional momentum x compared to the existing data. We argue that both experimental and phenomenological communities will benefit from the development of a comprehensive extraction framework that will facilitate the extraction of the 3D nucleon structure, help understand various assumptions in extraction and data analysis, help to insure the model independence of the experimental data and validate the extracted functions. In this paper we present the latest developments in the field of the spin asymmetries with emphasis on observables beyond the leading twist in SIDIS, indispensable for studies of the complex 3D nucleon structure, and discuss different components involved in precision extraction of the 3D partonic distribution and fragmentation functions.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

EXCHANGE Campaign 1: A Community-Driven Baseline Characterization of Soils, Sediments, and Water Across Coastal Gradients

The EXploration of Coastal Hydrobiogeochemistry Across a Network of Gradients and Experiments (EXCHANGE) program is a consortium of scientists working together to improve our understanding of how the two-way exchange of water between estuaries or large lake lacustuaries and the terrestrial landscape influence the state and function of ecosystems across the coastal interface. EXCHANGE Campaign 1 (EC1) focuses on the spatial variation in biogeochemical structure and function at the coastal terrestrial-aquatic interface (TAI). In the Fall of 2021, the EXCHANGE Consortium gathered samples from 52 TAIs. Samples collected from EC1 were analyzed for bulk geochemical parameters, bulk physicochemical parameters, organic matter characteristics, and redox-sensitive elements.Please download ec1_README.pdf for a complete list of available data in each .zip folder, package version history, and detailed information about the project. This README will serve as the central place for EC1 Data Package updates. Experimental setup and v1 methods are documented in Myers-Pigg and Pennington et al., 2023 (https://doi.org/10.1038/s41597-023-02548-7).EC1 Data Package Structure:ec1_README.pdfec1_methods.pdfec1_metadata_v3.zip...ec1_dd.csv...ec1_flmd.csv...ec1_sample_catalog.csv...ec1_metadata_kitlevel.csv...ec1_metadata_collectionlevel.csv...ec1_data_collectionlevel.csv...ec1_igsn_metadata.csvec1_soil_v3.zipec1_sediment_v3.zipec1_water_v3.zipec1_processingscripts_v3.zipThis data package is on v3 and was originally published May 2023 (v1). Subsequent updates will be published here with new version numbers. Please see the Change History section in ec1_README.pdf for detailed changes.---Acknowledging EXCHANGE: General Support and Data Product UseWe ask that users of EXCHANGE data add the following acknowledgement when publishing data in scholarly articles and data repositories:"This research is based on work supported by COMPASS-FME, a multi-institutional project supported by the U.S. Department of Energy, Office of Science, Biological and Environmental Research as part of the Environmental System Science Program."

54 ENVIRONMENTAL SCIENCES↗

Greenhouse gas and dissolved oxygen production and consumption rates associated with Regier et al. (2023)

Tidal inundation along the coastal terrestrial-aquatic interface controls soil and sediment biogeochemistry and gas dynamics. Although a rich literature exist on studies of the influence of tidal waters on the biogeochemistry of coastal ecosystem soils, few studies have experimentally addressed the reverse question: How do soils (or sediments) from different coastal ecosystems influence the biogeochemistry of the tidal waters that inundate them? We conducted short-term microcosm laboratory experiments where seawater was amended with sediments and soils collected across regional gradients of inundation exposure (i.e., frequently to rarely inundated) and measured changes in dissolved oxygen and greenhouse gas concentrations to calculate gas consumption or production rates occurring during seawater exposure to terrestrial materials. This data package contains dissolved oxygen and greenhouse gas data collected during incubation of soils and sediments collected at 18 sites, which were used in the publication Regier et al. (2023) entitled “Coastal inundation regime moderates the short-term effects of sediment and soil additions on seawater oxygen and greenhouse gas dynamics: a microcosm experiment” which is published in Frontiers in Marine Science (DOI: https://doi.org/10.3389/fmars.2023.1308590).---Acknowledging EXCHANGE: General Support and Data Product UseWe ask that users of EXCHANGE data add the following acknowledgement when publishing data in scholarly articles and data repositories:"This research is based on work supported by COMPASS-FME, a multi-institutional project supported by the U.S. Department of Energy, Office of Science, Biological and Environmental Research as part of the Environmental System Science Program."

54 ENVIRONMENTAL SCIENCES↗

Data for Machado-Silva et al. (2024), "Short-Term Groundwater Level Fluctuations Drive Subsurface Redox Variability"

This dataset contains the analytical data reported in Machado-Silva et al. (2024) as part of the COMPASS-FME project, which seeks to advance a scalable, predictive understanding of the fundamental biogeochemical processes, ecological structure, and ecosystem dynamics that distinguish coastal terrestrial-aquatic interfaces from the purely terrestrial or aquatic systems to which they are coupled. The dataset consists of water quality parameters as well as redox potential, water content, and electrical conductivity. These data were collected in 2022 in Crane Creek (CRC), Portage River (PTR), and Old Woman Creek (OWC). Each of these sites included uplands (UP), transitions (TR), wetland-transition edge (WTE), and wetland (W) zones. The sites represent replicates of the Lake Erie terrestrial-aquatic interface under fluctuating water levels and are located in well-preserved areas with natural or restored marsh and forest cover.This dataset consists of a single data file (Machado_Silva_et_al_2024_EST_data.csv) that is in comma-separated value (CSV) format. No special software is required to read it.This dataset uses the ESS-DIVE Hydrologic Monitoring Reporting Format 1.0.

54 ENVIRONMENTAL SCIENCES↗

Data for Wilson and Megonigal (2025), "Nitrate reduction across soils transitioning from coastal forest to wetland are hotspots for denitrification"

Sea level rise drives spatial migration of coastal ecosystems and can lead to the accelerated replacement of coastal forests with tidal wetlands. Soil biogeochemical cycles in steady-state upland and wetland ecosystems are well studied, but pathways and rates in rapidly changing ecosystems are largely unconstrained. Wilson and Megonigal (2025) performed a one-time sampling and a subsequent incubation experiment, and characterized the reduction of reactive nitrogen (N) via denitrification and dissimilatory nitrate reduction to ammonia. Sampling was done at four sites where coastal deciduous forest is undergoing ecosystem state change and becoming wetland throughout the Chesapeake Bay, USA. The COMPASS-FME project (http://compass.pnnl.gov) established the sites sampled in this study in 2022–2023.This dataset consists of:* Isotope-labeled incubation results comparing nitrate reduction rates across transects spanning upland, transition, and wetland; and* Ancillary porewater chemistry data.All files in this dataset are plain text, comma-separated value (CSV), and no special software is required to read them.

54 ENVIRONMENTAL SCIENCES↗

Soil microbial ecology and microbiome-metabolite linkages improve understanding of ecosystem states along terrestrial-aquatic interfaces

These data are from Bandopadhyay et al., "Soil microbial ecology and microbiome-metabolite linkages improve understanding of ecosystem states along terrestrial-aquatic interfaces". This study aims to understand the soil microbial ecology along terrestrial-aquatic interfaces of a freshwater and estuarine region and how it relates to organic matter. We analyzed soil microbial (16S rRNA gene) and organic matter (Fourier-transform ion cyclotron resonance mass spectrometry, FTICR-MS) composition from upland (forested), transition (stressed forest), and wetland positions at three sites in each of the Lake Erie (freshwater) and Chesapeake Bay (estuarine) regions. This dataset includes 16S rRNA gene amplicon data (only processed file types included here) and organic matter composition from FTICR-MS data (raw and processed files included here) from upland (forested), transition (stressed forest), and wetland positions at three sites in each of the Lake Erie and Chesapeake Bay regions. These sites are part of the COMPASS-FME project (https://compass.pnnl.gov/FME/COMPASSFME). File formats and software needed to access files: 16S rRNA gene amplicon data: These files follow the format reported here https://ess-dive.gitbook.io/amplicon-sequencing-reporting-format#updates-in-v1.0.1. As per this format, there are four file types reported: 1. Taxon tables (also called sequence-by-sample or OTU (operational taxonomic unit)/ESV (exact sequence variant) tables) : available in a .txt file format and accessible using TextEdit or MS Excel. 2. Representative sequences (also called consensus sequences) : available in a .fasta format and accessible using TextEdit. 3. Sequencing metadata : available in a MS Excel workbook file format and CSV file format 4. Bioinformatic metadata : available in a MS Excel workbook file format and CSV file format FTICR-MS data: 1. Raw data converted to a processed file with intensities of the peaks in the given samples : available in a MS Excel CSV file format 2. Processed file used in analyses and visualizations (appended as icr_long_) : available in a MS Excel CSV file format 3. Metadata file for ICR features (appended as icr_meta) : available in a MS Excel CSV file format

54 ENVIRONMENTAL SCIENCES↗

Data for Stetten et al. (2025), "Biogeochemical controls on iron speciation and cycling across upland to shoreline gradients in freshwater and estuarine coastal soils (Lake Erie and Chesapeake Bay, United States)"

Coastal environments are dynamic interfaces that mediate carbon and nutrient exchanges between terrestrial landscapes and open waters, but it is unclear how biogeochemical reactions, in particular iron (Fe) redox transformations, affect the understanding and prediction of coastal ecosystem functions. This dataset includes measurements from two freshwater sites in the Western and Central basins of Lake Erie (Ohio, United States) and two estuarine sites in the Chesapeake Bay (Maryland, United States); the analytical results were reported by Stetten et al. (2025) in Science of the Total Environment. It was produced as part of the COMPASS-FME project, which seeks to advance a scalable, predictive understanding of the fundamental biogeochemical processes, ecological structure, and ecosystem dynamics that distinguish coastal terrestrial-aquatic interfaces from the purely terrestrial or aquatic systems to which they are coupled. The sites were sampled in November 2022 (CRC), December 2022 (MSM), February 2023 (GCW), and March 2023 (OWC); site codes follow those used by Pennington et al. (2025).The dataset consists of the following soil data:- Solid data (Fe concentration, etc.)- Porewater data (sulfate, sulfide, etc.)- Linear combination fitting results of X-ray absorption near edge structure (XANES) spectra; i.e., quantitative results of the oxidation state of Fe, indicated as a proportion of pure Fe(III) and Fe(II) model compounds- Linear combination fitting results of EXAFS (extended X-ray absorption fine structure) spectra, indicated as proportion of of Fe-model compounds (illite, smectite, etc.)Each data type has a single file in comma-separated value (CSV) format. No special software is required to read it.

54 ENVIRONMENTAL SCIENCES↗

Magnetization of Materials in Pulsed Magnetic Fields

Magnetism has proven pivotal in the development of many technologies. From navigation compasses, imaging devices in medicine and electric motors, exploitation of the magnetic field on both the macroscopic and atomic scale has played an important role in human development. There is particular interest in the magnetic properties of materials, especially due to the incomplete understanding of why some materials behave magnetically in a specific manner. This has been motivated in some cases by the desire to engineer compounds to fulfil specific roles. One group of compounds being investigated for this purpose are known as molecular magnets, so-called as they are formed of discrete molecule-based units with metal ions providing a magnetic moment while organic or inorganic molecules bridge these metal centres. They can be large, discrete molecular clusters (referred to as 0-D molecular magnets) or long coordination networks in 1-D, 2-D or 3-D. The dimensionality here refers to the number of directions in which spins communicate: all directions (3-D), only in planes (2-D), only in chains (1-D) or no long range communication (0-D). These organometallic compounds, they are sometimes referred to as metal organic frameworks (MOFs) though there is some discrepancy in conventions in regards to whether MOFs should be different from molecular magnets. Molecular magnets offer flexible synthesis routes towards magnetic materials. Being transition complexes, ligands can be substituted to refine the magnetic properties of the final product or the metallic centre can be changed. This can be accomplished through as simple a method as different reactant ratios Materials with novel properties are also being sought such as magnetoelectric multiferroic compounds which display simultaneous ferromagnetism and ferroelectricity.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Dense Plasma Focus Modeling

The mechanisms for pinch formation in Dense Plasma Focus (DPF) devices, with the generation of high-energy ions beams and subsequent neutron production over a relatively short distance, are not fully understood. Here we report on high-fidelity 2D and 3D numerical magnetohydrodynamic (MHD) simulations using the LA-COMPASS code to study the pinch formation dynamics and its associated instabilities and neutron production.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

Next Generation Workload Management and Analysis System for Big Data

We report on the activities and accomplishments of a four-year project (a three-year grant followed by a one-year no cost extension) to develop a next generation workload management system for Big Data. The new system is based on the highly successful PanDA software developed for High Energy Physics (HEP) in 2005. PanDA is used by the ATLAS experiment at the Large Hadron Collider (LHC), and the AMS experiment at the space station. The program of work described here was carried out by two teams of developers working collaboratively at Brookhaven National Laboratory (BNL) and the University of Texas at Arlington (UTA). These teams worked closely with the original PanDA team – for the sake of clarity the work of the next generation team will be referred to as the BigPanDA project. Their work has led to the adoption of BigPanDA by the COMPASS experiment at CERN, and many other experiments and science projects worldwide.

97 MATHEMATICS AND COMPUTING↗

Dense Plasma Focus Modeling

Here we report on high-fidelity 2D and 3D numerical magnetohydrodynamic (MHD) simulations using the LA-COMPASS code to study the pinch formation dynamics in a DPF and the associated instabilities and neutron production.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

NESHAP Area-Specific Dose-Release Factors for Potential Onsite Member-of-the-Public Locations at SRS using CAP88-PC Version 4.0

The Environmental Protection Agency (EPA) requires the use of the computer model CAP88-PC to estimate the total effective doses (TED) for demonstrating compliance with 40 CFR 61, Subpart H (EPA 2006), the National Emission Standards for Hazardous Air Pollutants (NESHAP) regulations. As such, CAP88 Version 4.0 was used to calculate the receptor dose due to routine atmospheric releases at the Savannah River Site (SRS). For estimation, NESHAP dose-release factors (DRFs) have been supplied to Environmental Compliance and Area Closure Projects (EC&ACP) for many years. DRFs represent the dose to a maximum receptor exposed to 1 Ci of a specified radionuclide being released into the atmosphere. They are periodically updated to include changes in the CAP88 version, input parameter values, site meteorology, and location of the maximally exposed individual (MEI). In this report, the DRFs were calculated for potential radionuclide atmospheric releases from 13 SRS release points. The three potential onsite MEI locations to be evaluated are B-Area, Three Rivers Landfill (TRL), and Savannah River Ecology Lab Conference Center (SRELCC) with TRL’s onsite workers considered as members-of-the-public, and the potential future constructions of dormitories at SRELCC and Barracks at B-Area. Each MEI location was evaluated at a specified compass sector with different area to receptor distances and was conducted for both ground-level and elevated release points. The analysis makes use of area-specific meteorological data (Viner 2014). The resulting DRFs are compared to the 2014 NESHAP offsite MEI DRFs for three operational areas; A-Area, H-Area, and COS for a release rate of 1 Ci of tritium oxide at 0 ft. elevation. CAP88 was executed again using the 2016 NESHAP MEI release rates for 0 and 61 m stack heights to determine the radionuclide dose at TRL from the center-of-site (COS).

54 ENVIRONMENTAL SCIENCES↗

Research Library Year in Review 2016

2016 was a year of strategy, analysis and moving forward. We launched January with a strategic planning process. Building on the Lab’s Strategic Plan and Purpose Statement, we created a process that reached out to Lab leadership, scientists & engineers, and Research Library (RL) staff. An external consultant was engaged to help drive the process and to lead a fullday staff retreat. A survey was created and administered to staff, seeking feedback on priorities and direction. A parallel survey was created for stakeholders. Stakeholder questions began with the macro – from the external climate to Lab and division priorities – to the micro concerning priorities and directions for the RL. Stakeholders were personally interviewed by teams of two that included an interviewer and a scribe. These thirty-plus interviews were collated into a spreadsheet. A sociologist provided semantic analysis for the feedback, creating an impact document of the interviews. The full day retreat provided an opportunity for staff to build on their feedback as well as stakeholder feedback. A great deal of brainstorming led to categorized priorities and scenarios. The RL Compass Team, encompassing library leadership, moved the next stage of the process forward by taking retreat feedback and creating a first draft of a plan. Two more rounds of feedback with smaller staff groups as well as the Library Advisory Board led to the final plan. The core plan is included in this report.

96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗

Community Project for Accelerator Science and Simulation-3

The focus of the Rensselaer efforts for COMPASS-3 was the development of parallel mesh adaptation procedures for high-order unstructured meshes where elements must be curved to properly approximate the domain geometry. The procedures developed were integrated into the ACE3P accelerator modeling code. Areas of development included: High order curved mesh representations that can provide the orders of geometric approximation needed. A curved mesh adaptation procedure that can match an adaptively defined anisotropic mesh metric field. In-memory integration of these procedures with the Omega3P code to provide an effective parallel adaptive simulation work flow. Improved dynamic load balancing tools that account for the degrees of freedom associated with the various order mesh entities (vertices, edges, faces and regions).

42 ENGINEERING↗

Scoping Analysis of MACCS Modeling Improvements for the Study of Protective Action Recommendations

In late 2004, the U.S. Nuclear Regulatory Commission (NRC) initiated a project to analyze the relative efficacy of alternative protective action strategies in reducing consequences to the public from a spectrum of nuclear power plant core melt accidents. The study is documented in NUREG/CR-6953, “Review of NUREG-0654, Supplement 3, ‘Criteria for Protective Action Recommendations for Severe Accidents,’” Volumes 1, 2, and 3. The Protective Action Recommendations (PAR) study provided a technical basis for enhancing the protective action guidance contained in Supplement 3, “Guidance for Protective Action Strategies,” to NUREG-0654/FEMA-REP-1, Rev. 1, “Criteria for Preparation and Evaluation of Radiological Emergency Response Plans and Preparedness in Support of Nuclear Power Plants, ” dated November 2011. In the time since, a number of important changes and additions have been made to the MACCS code suite, the nuclear accident consequence analysis code used to perform the study. The purpose of this analysis is to determine whether the MACCS results used in the PAR study would be different given recent changes to the MACCS code suite and input parameter guidance. Updated parameters that were analyzed include cohorts, keyhole evacuation, shielding and exposure parameters, compass sector resolution, and a range of source terms from rapidly progressing accidents. Results indicate that using updated modeling assumptions and capabilities may lead to a decrease in predicted health consequences for those within the emergency planning zone compared to the original PAR study.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

Towards Combined QCD Global Analysis of Polarized and Unpolarized PDFs and Fragmentation Functions

We present a new global QCD analysis of spin-dependent PDFs (SPDF) and fragmentation functions (FF) performed by the JAM (Jefferson Lab Angular Momentum) Collaboration, based on all available data on inclusive spin structure functions from CERN, SLAC, DESY and JLab, and all semi-inclusive hadron production data from electron-positron annihilation experiments, including the most resent measurements from Belle and BaBar. Preliminary results on combined SPDFs and FFs using polarized semi-inclusive data from COMPASS and HERMES will be presented.

Sato, N.↗