Physics

General Physics Research Projects

Collaborative Research: Nuclear Spin Optical Rotation of Hyperpolarized Liquids and Solids

Dr. Savukov, Igor – LANL/NMC Research Scientist, Joint Appointee

We propose to investigate nuclear spin optical rotation (NSOR) effect of hyperpolarize liquid and solid samples. The experiments will take place at TAMU, College Station, TX. The university has a dynamic nuclear polarization (DNP) machine that can produce highly polarized samples. We also conducted preliminary experiments of DNP-NSOR type during our previous NSF project. This project will extend the NSOR DNP experiments to enable various practical light-nuclear magnetic resonance spectroscopy. In addition to experiments, for which I will travel to TAMU, I will work on theory, based on DALTON open source molecular structure code. This code will be also install at TAMU on high-performance machines and a student that will be working at TAMU will assist me with numerical simulations. We would like to investigate isotope-labeled samples, for example with C-13, to understand the structure of molecules in the excited states, where light will serve as the probe of the excited states.

This research is funded by the National Science Foundation (NSF)

ExpandQISE: Track 1: Quantum Molecular Dynamics on Quantum Computers

Dr. Kendrick, Brian – LANL/NMC Research Scientist
Dr. Jayakrushna Sahoo – NMC Research Scientist

The main scientific goal is to learn how the quantum architectures can be employed for the simulation of the molecular dynamics component pertaining to any computational chemistry problem. This educational project will drive workforce development in quantum computing.

This is an NSF sponsored project lead by the Marquette University.

Steps Toward Direct Observation of the Alfven Wave Parametric Decay Instability in a Laboratory Plasma

Dr. Feiyu Li – NMC Research Scientist
Dr. Xiangrong Fu – LANL/NMC Research Scientist
Vijayshankar Yadav, NMC Research Scientist

We propose a few steps toward direct observation of Alfven wave parametric decay instability (PDI) on the Large Plasma Device (LAPD). It includes measurement of seeded PDI growth rates and direct observation of PDI under optimized conditions. The experiments will be guided by extensive hybrid simulations using the exact LAPD physics conditions.

This project is sponsored by DOE.

Scaling studies of seeded Alfven wave parametric decay instability in the laboratory

Dr. Feiyu Li – NMC Research Scientist
Dr. Xiangrong Fu – LANL/NMC Research Scientist
Vijayshankar Yadav, NMC Research Scientist

Concrete steps to demonstrate the basic process of Alfven wave parametric decay instability (PDI) in the laboratory and study its scaling with varying parameters and configurations.

Alfven waves are ubiquitous throughout the heliosphere. The dissipation of large Alfvenic fluctuations originating from the Sun is key to many heliophysical processes such as solar coronal heating and solar wind acceleration. Parametric decay instability (PDI) is a nonlinear dissipation process of large-amplitude Alfven wave, where a forward pump Alfven wave decays into a backward daughter Alfven wave and a forward ion acoustic wave. The PDI process is fundamental because it provides an important means for driving solar wind heating and turbulence. However, direct spacecraft observation of the PDI dynamics is very limited, stimulating our interest in the study of PDI in a controlled laboratory environment. Objectives: Motivated by our recent experimental and computational progress, we aim to study seeded Alfven wave PDI in the laboratory using the Large Plasma Device (LAPD) at UCLA. We plan to seed the decay of the pump Alfven wave with a counter-propagating small-amplitude Alfven wave, thus relaxing the conditions normally required to study PDI physics. Specifically, we aim to address: 1) How does the seeded PDI growth rate in a uniform background magnetic field scale with plasma and antenna parameters? How do these scaling relations compare with existing theories and hybrid simulations? 2) How does the inhomogeneity of the background magnetic field (common in space plasmas) affect the growth of seeded PDI? We are especially interested in regimes where dimensionless parameters match that of the lower coronal region. Methods & Impact: Both laboratory experiments and first-principle computer simulations will be used to study the seeded PDI process. Wave and plasma parameters can be well controlled in laboratory experiments and detailed diagnostics will enable thorough examination of the process. Our hybrid simulation tool with realistic device scales, boundary conditions, and wave injection is suitable for aiding in both experimental design and interpretation of experimental results. The outcome of the proposed study will advance our understanding of the fundamental PDI process and aid future studies to evaluate the effectiveness of PDI in heating/accelerating the solar wind very close to the Sun. The study will also validate theoretical models and the computational tool, which are essential for interpreting spacecraft observations and evaluating the roles of Alfven wave PDI in space plasmas in different parameter regimes.

This project is sponsored by NASA.

PAST PROJECTS

CRCNS – Microimaging/modeling of Retinal Responses Measured with Laser Magnetometers
Effects of the Field Shear and Flow Shear on the Kinetic Physics and Particle Acceleration of Relativistic Reconnection
PLASMA PHYSICS: Turbulence and Particle Energization in Low-Beta Plasmas