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View article: Speeding up charge exchange recombination spectroscopy analysis in support of NERSC/DIII-D realtime workflow
Speeding up charge exchange recombination spectroscopy analysis in support of NERSC/DIII-D realtime workflow Open
We report optimization work made in support of the development of a realtime Superfacility workflow between DIII-D and NERSC. At DIII-D, the ion properties measured by charge exchange recombination (CER) spectroscopy are required inputs fo…
View article: Data Preservation for Cosmology
Data Preservation for Cosmology Open
We describe the needs and opportunities for preserving cosmology datasets and simulations, and facilitating their joint analysis beyond the lifetime of individual projects. We recommend that DOE fund a new cosmology data archive center to …
View article: The LBNL Superfacility Project Report
The LBNL Superfacility Project Report Open
The Superfacility model is designed to leverage HPC for experimental science. It is more than simply a model of connected experiment, network, and HPC facilities; it encompasses the full ecosystem of infrastructure, software, tools, and ex…
View article: LBNL Superfacility Project Report
LBNL Superfacility Project Report Open
The Superfacility model is designed to leverage HPC for experimental science. It is more than simply a model of connected experiment, network, and HPC facilities; it encompasses the full ecosystem of infrastructure, software, tools, and ex…
View article: Fusion Energy Sciences Network Requirements Review (Final Report)
Fusion Energy Sciences Network Requirements Review (Final Report) Open
The Energy Sciences Network (ESnet) is the high-performance network user facility for the US Department of Energy (DOE) Office of Science (SC) and delivers highly reliable data transport capabilities optimized for the requirements of data-…
View article: Data Preservation for Cosmology
Data Preservation for Cosmology Open
We describe the needs and opportunities for preserving cosmology datasets and simulations, and facilitating their joint analysis beyond the lifetime of individual projects. We recommend that DOE fund a new cosmology data archive center to …
View article: Podman-hpc v1.0
Podman-hpc v1.0 Open
We have developed some scripts and tools that compliment an existing open-source product (Podman, https://podman.io/). This enables podman to function as a high-performance container solution. This capability is similar to Shifter and Sing…
View article: Near real-time streaming analysis of big fusion data
Near real-time streaming analysis of big fusion data Open
Experiments on fusion plasmas produce high-dimensional data time series with ever-increasing magnitude and velocity, but turn-around times for analysis of this data have not kept up. For example, many data analysis tasks are often performe…
View article: Customs: Inspect and Report Python Imports (customs) v1.0.0
Customs: Inspect and Report Python Imports (customs) v1.0.0 Open
We have developed a simple, minimally invasive monitoring framework that enables us to capture key metrics from Python user processes. This is part of a larger effort to collect data across our entire data-intensive science workload at NER…
View article: Accelerating Spectroscopic Data Processing Using Python and GPUs on NERSC Supercomputers
Accelerating Spectroscopic Data Processing Using Python and GPUs on NERSC Supercomputers Open
The Dark Energy Spectroscopic Instrument (DESI) will create the most detailed 3D map of the Universe to date by measuring redshifts in light spectra of over 30 million galaxies. The extraction of 1D spectra from 2D spectrograph traces in t…
View article: Monitoring Scientific Python Usage on a Supercomputer
Monitoring Scientific Python Usage on a Supercomputer Open
In 2021, more than 30\% of users at the National Energy Research Scientific Computing Center (NERSC) used Python on the Cori supercomputer. To determine this we have developed and open-sourced a simple, minimally invasive monitoring framew…
View article: Optimizing Python-Based Spectroscopic Data Processing on NERSC Supercomputers
Optimizing Python-Based Spectroscopic Data Processing on NERSC Supercomputers Open
We present a case study of optimizing a Python-based cosmology data processing pipeline designed to run in parallel on thousands of cores using supercomputers at the National Energy Research Scientific Computing Center (NERSC).
View article: Optimizing Python-Based Spectroscopic Data Processing on NERSC Supercomputers
Optimizing Python-Based Spectroscopic Data Processing on NERSC Supercomputers Open
A case study in profiling and optimizing an image processing application for NERSC supercomputer systems
View article: Observation of Marfes in the Wendelstein 7-X stellarator with inboard limiters
Observation of Marfes in the Wendelstein 7-X stellarator with inboard limiters Open
In the first operational campaign of the Wendelstein 7-X (W7-X) stellarator we observed Marfe-like radiation belts at the plasma edge. We describe and analyze the behaviour of these radiation belts, especially with respect to the high dens…
View article: Impact of magnetic islands in the plasma edge on particle fueling and exhaust in the HSX and W7-X stellarators
Impact of magnetic islands in the plasma edge on particle fueling and exhaust in the HSX and W7-X stellarators Open
The edge magnetic structure in the Helically Symmetric eXperiment (HSX) and Wendelstein 7X (W7-X) stellarators has been shown to have a significant impact on the particle fueling and exhaust of the plasma main species (hydrogen) as well as…
View article: Development of a 3-D visible limiter imaging system for the HSX stellarator
Development of a 3-D visible limiter imaging system for the HSX stellarator Open
A visible camera diagnostic has been developed to study the Helically Symmetric eXperiment (HSX) limiter plasma interaction. A straight line view from the camera location to the limiter was not possible due to the complex 3D stellarator ge…
View article: Overview of the plasma-surface interaction on limiter surfaces in the startup campaign of Wendelstein 7-X
Overview of the plasma-surface interaction on limiter surfaces in the startup campaign of Wendelstein 7-X Open
The first operational campaign of Wendelstein 7-X (W7-X) provided an excellent environment for the study of plasma-surface interaction (PSI) in a stellarator. In situ spectroscopic analysis via a combined visible/infrared camera system and…
View article: Effect of error field correction coils on W7-X limiter loads
Effect of error field correction coils on W7-X limiter loads Open
In the first campaign Wendelstein 7-X was operated with five poloidal graphite limiters installed stellarator symmetrically. In an ideal situation the power losses would be equally distributed between the limiters. The limiter shape was de…
View article: Reconstruction of recycling flux from synthetic camera images, evaluated for the Wendelstein 7-X startup limiter
Reconstruction of recycling flux from synthetic camera images, evaluated for the Wendelstein 7-X startup limiter Open
The interpretation of spectroscopic measurements in the edge region of high-temperature plasmas can be guided by modeling with the EMC3-EIRENE code. A versatile synthetic diagnostic module, initially developed for the generation of synthet…
View article: Confinement in Wendelstein 7-X limiter plasmas
Confinement in Wendelstein 7-X limiter plasmas Open
Observations on confinement in the first experimental campaign on the optimized Stellarator Wendelstein 7-X are summarized. In this phase W7-X was equipped with five inboard limiters only and thus the discharge length restricted to avoid l…
View article: Limiter observations during W7-X first plasmas
Limiter observations during W7-X first plasmas Open
During the first operational phase (referred to as OP1.1) of the new Wendelstein 7-X (W7-X) stellarator, five poloidal graphite limiters were mounted on the inboard side of the vacuum vessel, one in each of the five toroidal modules which …
View article: Numerical investigation of plasma edge transport and limiter heat fluxes in Wendelstein 7-X startup plasmas with EMC3-EIRENE
Numerical investigation of plasma edge transport and limiter heat fluxes in Wendelstein 7-X startup plasmas with EMC3-EIRENE Open
Here the results of a first systematic assessment of plasma edge transport processes for the limiter startup configuration at Wendelstein 7-X are presented. This includes an investigation of transport from intrinsic and externally injected…
View article: Overview of diagnostic performance and results for the first operation phase in Wendelstein 7-X (invited)
Overview of diagnostic performance and results for the first operation phase in Wendelstein 7-X (invited) Open
Wendelstein 7-X, a superconducting optimized stellarator built in Greifswald/Germany, started its first plasmas with the last closed flux surface (LCFS) defined by 5 uncooled graphite limiters in December 2015. At the end of the 10 weeks l…
View article: Synthetic plasma edge diagnostics for EMC3-EIRENE, highlighted for Wendelstein 7-X
Synthetic plasma edge diagnostics for EMC3-EIRENE, highlighted for Wendelstein 7-X Open
Interpretation of spectroscopic measurements in the edge region of high-temperature plasmas can be a challenge since line of sight integration effects make direct interpretation in terms of quantitative, local emission strengths often impo…
View article: A high resolution IR/visible imaging system for the W7-X limiter
A high resolution IR/visible imaging system for the W7-X limiter Open
A high-resolution imaging system, consisting of megapixel mid-IR and visible cameras along the same line of sight, has been prepared for the new W7-X stellarator and was operated during Operational Period 1.1 to view one of the five inboar…
View article: Spectroscopic imaging of limiter heat and particle fluxes and the resulting impurity sources during Wendelstein 7-X startup plasmas
Spectroscopic imaging of limiter heat and particle fluxes and the resulting impurity sources during Wendelstein 7-X startup plasmas Open
A combined IR and visible camera system [G. A. Wurden et al., “A high resolution IR/visible imaging system for the W7-X limiter,” Rev. Sci. Instrum. (these proceedings)] and a filterscope system [R. J. Colchin et al., Rev. Sci. Instrum. 74…
View article: Three-dimensional scrape off layer transport in the helically symmetric experiment HSX
Three-dimensional scrape off layer transport in the helically symmetric experiment HSX Open
The edge topology of helically symmetric experiment (HSX) in the quasi-helically symmetric configuration is characterized by an 8/7 magnetic island remnant embedded in a short connection length scrape-off layer (SOL) domain. A 2D mapping o…