Alex Zylstra

  • Academic Institution: Massachusetts Institute of Technology
  • Program Year: 4
  • Practicum(s):
    Lawrence Livermore National Laboratory (2011)
    Los Alamos National Laboratory (2013)
  • Degree(s):
    B.A. Physics, Pomona College, 2009
  • Field of Study: Physics
  • Academic Advisor: Richard Petrasso

Summary of Research:

In Inertial Confinement Fusion (ICF) a small pellet of deuterium and tritium is compressed with lasers to over 10^8 degrees Kelvin. The DT fusion reaction starts a chain reaction, which produces energy. If the chain reaction is self-sustaining the fuel is “ignited” and has the potential for energy gain. The long-term goal of this research field is to be able to produce abundant and clean fusion energy to meet the world’s power needs.

Our group develops diagnostics and explores the physics of ICF and general HEDP plasmas at the OMEGA and National Ignition Facility (NIF) laser facilities. These diagnostics include charged particle and neutron spectrometers, neutron yield measurements, charged-particle radiography methods and fast nuclear burn timing diagnostics. The spectrometers used are crucial to inferring various parameters of the implosions and the radiography project has been exploring electromagnetic fields spontaneously generated in ICF implosions. Both of these research areas are fundamentally important to achieving ignition at the NIF.

My work includes leading the Wedge Range Filter (WRF) proton spectrometer team at the NIF. The WRFs collect data on gas-filled and cryogenic implosions as part of the National Ignition Campaign (NIC). Such data are being used in conjunction with other diagnostics to constrain physics models of the implosions. I am also working on basic physics experiments at the OMEGA laser facility to study charged-particle stopping powers in plasmas, and conducting measurements of astrophysically-relevant nuclear reactions for proton-proton burning stars like our sun using ICF plasmas.

Publications:

Papers:
Charged-particle spectroscopy for diagnosing shock ρR and strength in NIF implosions. A. B. Zylstra et al., Rev. Sci. Instrum. 83, 10D901 (2012).
Measurements of hohlraum-produced fast ions. A. B. Zylstra et al., Phys. Plasmas 19, 042707 (2012).
A new model to account for track overlap in CR-39 data. A. B. Zylstra et al., Nuclear Instruments and Methods in Physics Research A, 681 (2012).
Using high-intensity laser-generated energetic protons to radiograph directly driven implosions. A. B. Zylstra et al., Rev. Sci. Instrum. 83, 013511 (2012).
Increasing the energy dynamic range of solid-state nuclear track detectors using multiple surfaces. A. B. Zylstra et al. Rev. Sci. Instrum. 82, 083301 (2011).
Ion velocity distribution measurements in a magnetized laser plasma expansion. A. B. Zylstra et al. J. Instr. 5 (2010).
1-D Van der Waals Foams Heated by Ion Beam Energy Deposition. A. B. Zylstra, J. J. Barnard, R. M. More. High Energy Density Physics 6 (2010).
Regime transitions in the viscous catenary. A. Zylstra and C. Mitescu. EPL 87 (2009).

Talks:
-Charged-particle measurements of ρR symmetry at shock-bang-time in NIF implosions, APS DPP 2012.
-Charged-particle measurements of ρR symmetry at shock-bang-time in NIF implosions, APS DPP 2011.
-FSC Sponsored Diagnostics and Analysis Support of the National Ignition Campaign (NIC), FSC 2011.
-5 key nuclear diagnostics implemented by MIT and collaborators for the NIC, SSAA 2011.
-Diagnosing ρR and ρR asymmetries in NIF implosions using D3He protons, APS DPP 2010.

Posters:
First Stellar Nucleosynthesis Experiments Using ICF Plasmas, SSGF 2012.
Compact proton spectrometers for measurements of shock ρR and strength in NIF implosions, HTPD 2012.
Charged-particle spectroscopy for diagnosing NIF implosions and for conducting basic science, OMEGA Laser User's Group Meeting 2012.
Charged-particle spectroscopy for diagnosing NIF implosions and for conducting basic science, SSAA 2012.
Charged-particle spectroscopy for diagnosing NIF implosions and for conducting basic science, NIF User's Group Meeting 2012.
-MIT-led ρR measurements at the NIF, SSGF 2011.
-Diagnosing ρR and ρR asymmetries in NIF implosions using proton spectroscopy, OMEGA Laser User’s Group 2011.
-Studies of the HD reaction: Next step in HEDP laboratory nuclear astrophysics, OMEGA Laser User’s Group 2011.
-Diagnosing NIF Implosions, SSGF 2010.
-Diagnosing OMEGA and NIF Implosions Using the D3He Spectrum Line Width,
OMEGA Laser User’s Group 2010.
-Improving the Dynamic Range of CR39 Detectors for ICF Experiments Through Multiple Track Overlap Detection Algorithms, APS DPP 2009.
-Plasma Diagnostics for a Laser Driven Expansion into a Large Ambient Magnetized Plasma, APS DPP 2008.

Awards:

-NIF and Photon Science Directorate Performance Award, 2011.
-Tileston Pomona Physics Department Prize: 2006, 2007, 2008.
-Nominated to Sigma Xi (associate member), March 2007.
-Pomona College Scholar: Spring 2007, Spring 2008, Fall 2008.