Oliver C. Gorton
ACT Award scholar at Lawrence Livermore National Laboratory
Ph.D. in Computational Science (Computational Nuclear Physics)
ogorton@sdsu.edu
Github
Google
Scholar
ORC ID: 0000-0003-3643-9640
Research interests
Nuclear structure and reactions: beta-delayed neutron
emission, integration of nuclear shell-model and Hauser-Feshbach
(statistical) reactions. Applications in related fields: the
search for dark matter, nuclear data and evaluations, uncertainty
quantification, machine learning, high-performance computing.
Education
Training and schools
Awards and support
Research experience
Nuclear reactions, data, and theory at Lawrence Livermore
National Laboratory (2018 – Present)
- High Energy Density Physics Intern, Strategic Deterrence (Summer
2018)
- Developed code, COMMCAS, to perform uncertainty quantification on
Hauser-Feshbach code STAPRE.
- Applied method to benchmark calculation of surrogate reaction
method, resulting in conference proceedings [C3] listed below.
- High Energy Density Physics Intern, Strategic Deterrence (Summer
2019)
- Further developed and applied COMMCAS for sensitivity analysis of
surrogate reaction theory, leading to journal paper [J3] listed
below.
- Initiated collaboration with experimentalists at U. Notre Dame to
analyze cross section measurements, leading to journal paper [J4] listed
below.
- High Energy Density Physics Intern, Strategic Deterrence (Summer
2020)
- Further improvements to COMMCAS and integration with various nuclear
reaction codes including EMPIRE, TALYS, YAHFC.
- Found and reported bugs in lab’s new reaction code YAHFC
- Assisted in feasibility study to determine if and how a Livermore
C++ physics code could be ported to GPUs.
- Glenn T. Seaborg Institute (GTSI) Summer Intern, Seaborg Institute (Summer 2021)
- Collaborated with 2021 summer student to integrate COMMCAS with
Livermore machine learning tool B-DJINN for emulation of reaction
codes.
- Co-refereed an article for Physical Review C
- ACT-UP
Scholar, Strategic Deterrence (2022 – 2023)
- Collaborated with 2022 summer student to improve COMMCAS machine
learning tools with neural networks, contributing to conference
proceedings [C2] listed below.
- New predictive capability for reaction and decay properties of
fission fragments
- Implemented shell model methods for computing gamma-ray strength
functions.
Nuclear structure and applications at San Diego State
University (2016 – Present)
- Masters and Doctoral student with Calvin Johnson
- Helped apply quantum information theory to nuclear shell model,
leading to journal paper [J1]
- Co-developed a truncated shell model code.
- Implemented advanced extremal eigenvalue solvers in modern
Fortran.
- Solved several technical problems related to implementing a quantum
many-body solver.
- Parallelized a shell model code using a hybrid MPI and openMP
approach.
- Co-developed a nucleus-WIMP scattering code for direct dark matter
detection experiments, resulting in journal paper [J2] listed
below.
Intersection of nuclear physics and quantum chemistry at UC,
Irvine (2019-20 academic year)
- Graduate Student Visitor, Department of Chemistry, Furche Research
Group
Collaborated with chemistry postdoc to develop formalism for
Nuclear-Electronic Orbital method using time-dependent density
functional theory.
Codes
Languages: Modern Fortran, Python (numpy, scipy, MPI4py,
multiprocessing, emcee), Bash, C++
Technologies: Experienced: MPI, openMP, git; Novice: CUDA, RAJA
Machines: Borax, Quartz in LC, LLNL
facility
Primary developer of:
- dmscatter [Repository]
A fast Fortran code for WIMP-nucleus form factors and differential event
rate spectra. Modern Fortran with Python interface. OpenMP parallel.
- Journal publication [J2] listed below with multiple citations
- Being used and applied in upcoming publication
- PANASh [Not yet released]
Proton and neutron approximate shell model code providing advanced basis
truncation scheme for nuclei away from stability. MPI and openMP hybrid
parallel.
- Motivated by journal publication [J1] listed below with multiple
citations
- Has been applied in conference proceedings [C1] listed below
- Separate Journal publication in progress
- COMMCAS [Not yet released]
Computational Model Monte Carlo Sampler: Uncertainty quantification
framework originally designed for Hauser-Feshbach statistical decay
codes, now provides generic data-fitting, uncertainty quantification,
and neural-network-emulation tools for physics codes. MPI and
multiprocessing parallel.
- Actively in use at LLNL for uncertainty quantification in:
- Surrogate reaction theory
- Optical model potentials
- Has been applied in Journal papers [J3, J4], and Conference
proceedings [C2, C3]
- Wigner [Repository]
A library of functions for computation of Wigner 3-j, 6-j and 9-j
symbols, written in modern Fortran.
Journal papers
- Proton-neutron
entanglement in the nuclear shell model
C. W. Johnson and O. C. Gorton
Journal of Physics G: Nuclear and Particle Physics 50 (4) 045110
(2023) | arXiv:2210.14338
- dmscatter: A
Fast Program for WIMP-Nucleus Scattering
O. Gorton, C. Johnson, C. Jiao, J. Nikoleyczik
Computer Physics Communications 284, 108597 (2023) | arXiv:2209.09187
- Cross sections
for neutron-induced reactions from surrogate data: Reexamining the
Weisskopf-Ewing approximation for (n,n’) and (n,2n) reactions
O. C. Gorton and J. E. Escher
Physical Review C: Nuclear Physics 107 (4), 044612 (2023) | arXiv:2102.03452
- Measurements
of proton capture in the A=100-110 mass region: Constraints of the
111In(gamma,p)/(gamma,n) branching point relevant to the
gamma-process
O. Olivas-Gomez, A. Simon, O. Gorton, J. E. Escher et al.
Physical Review C: Nuclear Physics 102 (5), 055806 (2020)
Conference proceedings
- A Problem in
the Statistical Description of Beta-Delayed Neutron Emission
O. Gorton, C. Johnson, and J. Escher
EPJ Web of Conferences 284, 03013 (2023) | arXiv:2210.05904
- Improving
nuclear data evaluations with predictive reaction theory and indirect
measurements
J. Escher, K. Bergstrom, E. Chimanski, O. Gorton, E. J. In, M. Kruse, S.
Peru, C. Pruitt, R. Rahman, E. Shinkle, A. Thapa, W. Younes
EPJ Web of Conferences 284, 03012 (2023) | arXiv:2304:10034
- Neutron
capture cross sections from surrogate reaction data and theory:
connecting the pieces with a Markov-Chain Monte Carlo approach
O. Gorton and J. E. Escher
Springer Proceedings in Physics, vol 254, pages 229-231 (2021)
| arXiv:1905:03055
Contributed talks
- Gamma-ray
strength functions using approximate shell model calculations
O. Gorton, C. Johnson, J. Escher
Talk at T3 “Taking the Temperature” Workshop on Statistical Nuclear
Physics for Astrophysics and Applications (Ohio University, August
2023)
- Nuclear
Shell Model to the Rescue: Efforts to Resolve a Mystery in Beta Delayed
Neutron Emission
O. Gorton, C. Johnson, J. Escher
Talk at APS Division of Nuclear Physics Fall 2022 Meeting (New Orleans,
October 2022)
- Crisis in
Beta-Delayed Neutron Emission: Shell Model to the Rescue
O. Gorton, C. Johnson, J. Escher
Talk at Nuclear Data Conference (Sacramento – virtual, July 2022)
- DMFortFactor: A
Fast and Accessible for Computing WIMP-Nucleus-Scattering
Event-Rates
O. Gorton, C. Johnson, C. Jiao
Talk at DNP21 APS Conference (Boston – virtual, October 2021)
- Better
MCMC for Nuclear Data using emcee and B-DJINN
O. C. Gorton, J. E. Escher, K. O. Bergstrom, M. K. Kruse
Talk at LLNL Summer Slam (Livermore, August 2021)
- Nuclear
Physics for WIMPs
O. Gorton and C. W. Johnson
Talk at SDSU SIAM Student Chapter Summer Colloquium Series, (San Diego,
July 2021)
- Cross
subsections for neutron reactions from surrogate measurements:
Revisiting the Weisskopf-Ewing approximation
O. Gorton and J. E. Escher
Talk at DNP20 APS Conference (New Orleans – virtual, October 2020)
- Can we
get rid of the theorists?
O. Gorton and J. E. Escher
Talk at LLNL Summer Slam (Livermore, August 2020)
- Big
Picture and Background for Nuclear-Electronic Orbital (NEO) Approach:
Calculating Mixed Nucleon-Electron Wave Functions
O. Gorton
Seminar for the Furche Group, Chemistry Department, UC Irvine (Irvine,
March 2020)
- Indirect
measurements of nuclear cross subsections: tempering experimental
results with theory
O. Gorton and J. E. Escher
Seminar for HEDP Intern Exit Talk (Livermore, September 2019)
- A Markov
Chain Monte Carlo Tool for Hauser-Feshbach Codes
O. Gorton and J.E. Escher
Seminar for HEDP Intern Exit Talk (Livermore, August 2018)
Posters
- Proton
and Neutron Approximate Shell Model: Factorization-based Importance
Truncation
O. Gorton, C. Johnson, J. Escher
Poster at Nuclear Structure Conference (Berkeley, June 2022)
- Sensitivity
Study of the Surrogate Method
O. Gorton and J. E. Escher
Poster at LLNL Student Poster Symposium (Livermore, August 2019)
- Temperature
and Entropy in the Nuclear Shell Model
O. Gorton and C. W. Johnson
Poster at SDSU ACCESS event (San Diego, April 2019)
- Proton
Neutron Interacting Shell Model: Order of Magnitude Reduction for Medium
Mass Nuclei
O. Gorton and C. Johnson
Poster at SDSU annual research symposium (San Diego, March 2019)
- Neutron
capture cross subsections from surrogate reaction data and theory:
connecting the pieces with a Markov-Chain Monte Carlo approach
O. Gorton and J. E. Escher
Poster at Compound Nuclear Reactions conference CNR18 (Berkeley, September
2018)
Teaching
- Graduate Teaching Associate for intro physics lab courses (2016 -
2020)
San Diego State University, Department of Physics