Arjun Shankar
Division Director
Dr. Mallikarjun (Arjun) Shankar is the Division Director for the National Center for Computational Science and the Oak Ridge Leadership Computing Facility (OLCF) at the Oak Ridge National Laboratory. His research focuses on the interdisciplinary bridge between computer science and large-scale scientific discovery campaigns that rely on scalable computing and data science. He is a joint faculty appointee at the University of Tennessee’s Bredesen Center, a senior member of the IEEE and a senior member of the ACM.
Ashley Barker
Program Director, Oak Ridge Leadership Computing Facility
Ashley Barker serves as the Program Director for the Oak Ridge Leadership Computing Facility at the Department of Energy’s Oak Ridge National Laboratory. Barker oversees day-to-day operations of the OLCF, including progress on the OLCF-6 Project, to deliver the lab’s next supercomputer. The OLCF, a DOE Office of Science user facility, has deployed 4 of the world’s fastest supercomputers in its 29-year history. The facility is managed by the National Center for Computational Sciences division at ORNL, which offers expertise in high performance computing, data, storage, training, and user support for a global user community.
Bronson Messer
Director of Science
Bronson Messer is a Distinguished Scientist and Director of Science at the Oak Ridge Leadership Computing Facility (OLCF) at ORNL. His primary research interests are related to the explosion mechanisms and phenomenology of supernovae (both thermonuclear and core-collapse), especially neutrino transport and signatures, dense matter physics, and the details of turbulent nuclear combustion.
Matt Sieger
Project Director
Matt Sieger is the OLCF-6 Project Director for the Oak Ridge Leadership Computing Facility (OLCF). In 2018 Matt moved to the OLCF as Deputy Project Director for the Frontier project, and in 2021 was selected to lead the effort to procure the successor to Frontier.
Jim Rogers
Director, Computing and Facilities
Jim Rogers is the Computing and Facilities Director for the National Center for Computational Science at the Oak Ridge National Lab. He has primary responsibility for the strategy, acquisition, delivery, integration, and transition to production for high performance computing, storage, networking, and analysis systems as well as the physical facilities that house these systems. He manages recurring operational activities for both the NCCS systems and the supporting facility/infrastructure . These activities extend across multiple Federal customers.
Kevin Thach
Section Head, HPC Systems
As the Section Head for HPC Systems, Kevin manages six operationally focused groups responsible for the support of the NCCS’s computing, networking, and storage systems--including general support of critical computational and facilities-related infrastructure and systems. The section's groups administer and support high-speed parallel file systems and archive capabilities, and develop tools and administer data management platforms to ensure security, operational, and laboratory policy compliance.
Verónica Melesse Vergara
Section Head, Operations
Verónica G. Melesse Vergara has over a decade of experience in the high performance computing field and is currently the Section Head for Operations in the National Center for Computational Sciences (NCCS) at Oak Ridge National Laboratory. She previously served as the Group Leader of the System Acceptance and User Environment Group in NCCS in support of the Oak Ridge Leadership Computing Facility (OLCF). In addition to providing assistance to OLCF users, Verónica is part of the systems testing team, led acceptance for Summit, and is leading acceptance for Frontier, ORNL's exascale supercomputer. Her research interests include high performance computing, large-scale system testing, and performance evaluation and optimization of scientific applications. Verónica is a member of both IEEE and ACM and serves in the ACM SIGHPC Executive Committee and the SC Steering Committee.
Tom Beck
Section Head, Science Engagement
Tom Beck is the Section Head for Science Engagement for the National Center for Computational Sciences (NCCS) located at Oak Ridge National Laboratory (ORNL). The NCCS Science Engagement Section partners NCCS users with experts in scientific domains and computation to obtain optimal scientific results from the center’s leadership class computational resources and systems. The members of this section include experts in the chemical and materials sciences; in nuclear physics, such as nuclear structure and quantum chromodynamics; in high energy physics, such as particle physics; in astrophysics, such as stellar evolution and cosmology; and in climate science, geophysics, biology, biomedical sciences, and engineering. Additionally, this section works to improve algorithms and application performance. The section seeks to expand the scope of high-impact projects utilizing the Oak Ridge Leadership Computing Facility (OLCF) in the continually evolving computational science landscape.
Sarp Oral
Section Head, Advanced Technologies
Dr. Sarp Oral is the Section Head for Advanced Technologies and a Distinguished Research Scientist at the National Center of Computational Sciences (NCCS) Division of Oak Ridge National Laboratory. He formerly served as the Group Leader for the Technology Integration Group. Sarp holds a PhD in Computer Engineering from University of Florida. He joined the ORNL in 2006 and his research and development interests are parallel I/O and file system technologies, benchmarking, high-performance computing and networking, fault-tolerance.
Scott Atchley
Chief Technology Officer
Scott is a Distinguished R&D Staff Member and he currently serves as the Chief Technology Officer for the National Center for Computational Science and the Oak Ridge Leadership Computing Facility. Scott focuses on compute, memory, and interconnect technology trends to understand how to optimize existing systems such as Frontier, how to prepare for next generation systems. Scott and the OLCF team are defining the requirements for OLCF-6, the system that will follow Frontier. His interests include resource heterogeneity within processors, within nodes, and across the system; processor architectures (e.g., CPU, GPU, FPGA, coarse-grained reconfigurable arrays); memory architectures and hierarchies; persistent memory; interconnects (e.g., PCIe, CXL, UCIe, InfiniBand, Ethernet); system scheduling; resilience; and system monitoring. Scott is the Technical Project Officer (TPO) for the OLCF's Frontier project and for OLCF-6 project, called Discovery.
T. P. Straatsma
Distinguished Research Scientist
Dr. T. P. Straatsma is Distinguished Research Scientist in the National Center for Computational Sciences, a division that houses the Oak Ridge Leadership Computing Facility, at Oak Ridge National Laboratory, and Adjunct Faculty member in the Chemistry Department of the University of Alabama in Tuscaloosa. He earned his Ph.D. in Mathematics and Natural Sciences from the University of Groningen, the Netherlands, and has authored or co-authored more than 100 scientific publications with over 14,000 citations, and edited a book on Exascale Scientific Applications.
Al Geist
Corporate Research Fellow and Frontier Project Director
Al Geist is a Corporate Research Fellow at Oak Ridge National Laboratory. He is the Chief Technology Officer of the Leadership Computing Facility and Chief Scientist for the Computer Science and Mathematics Division. He is also the Chief Technology Officer of the DOE Exascale Computing Project. His recent research is on Exascale computing and resilience needs of the hardware and software. He leads the ASCR technical Council on Resilience and is the PI on the multi-lab Extreme-Scale Algorithms and Software Institute.
Division Support
