Behind every great organization is a team with a vision. Meet the key decision-makers who are leading the one of nation’s top high performance computing centers.
The Team Behind the Vision
NCCS Org Chart (Updated Oct 2025) Download

Arjun Shankar
NCCS Division Director and OLCF Director

Ashley Barker
OLCF Program Director

Matt Sieger
OLCF-6 Project Director

Bronson Messer
OLCF Director of Science

Jim Rogers
Director, Computing and Facilities

Kevin Thach
Section Head, Systems

VerĂ³nica Melesse Vergara
Section Head, Operations

Tom Beck
Section Head, Science Engagement

Sarp Oral
Section Head, Advanced Technologies

Dustin Leverman
OLCF-6 Deputy Director

T. P. Straatsma
Distinguished Research Scientist

Paul Abston
Data Center Manager and Safety Officer

Tom Bundy
Quality Assurance Manager

Rachel Clauss
Human Resources Business Partner

David Langley
Finance Officer

Suzy Tichenor
Director, Industrial Partnerships

Sarah Crossley
Division Administrative Assistant

Kevin Thach
Section Head, Systems

Paul Abston
Group Leader, HPC Infrastructure Operations

Ryan Adamson
Group Leader, HPC Cyber Security & Information Engineering

Elton Cranfill
Group Leader, HPC Clusters

Travis Croxdale
Group Leader, HPC Networking

Jesse Hanley
Acting Group Leader, HPC Storage & Archive

Kevin Masteller
Group Leader, HPC Infrastructure

Zach Mayes
Acting Group Leader, HPC Platforms

Paul Peltz
Group Leader, HPC Scalable Systems

Sherry Chandler
Administrative Assistant

VerĂ³nica Melesse Vergara
Section Head, Operations

Katie Bethea
Group Leader, User Access, Outreach, & Communications

Chris Fuson
Group Leader, User Assistance

Rajesh Kalyanam
Group Leader, Data Platforms and Services

Fernando Posada
Group Leader, System Acceptance & User Environment

Sonya Mowery
Administrative Assistant

Tom Beck
Section Head, Science Engagement

Tom Beck
Acting Group Leader, HPC-Quantum

Reuben Budiardja
Group Leader, Advanced Computing for Nuclear, Particles, & Astrophysics

Matt Norman
Group Leader, Advanced Computing for Life Science & Engineering

Phil Roth
Group Leader, Algorithms & Performance Analysis

Dmytro Bykov
Group Leader, Advanced Computing for Chemistry & Materials

Myranda White
Administrative Assistant

Sarp Oral
Section Head, Advanced Technologies

Rafael Ferreira da Silva
Group Leader, Workflows and Ecosystem Services

Feiyi Wang
Group Leader, Analytics and AI Methods at Scale

Chris Zimmer
Group Leader, Technology Integration

Jessica Whitt
Administrative Assistant