Wingnut and I
John Liptac
175 Albany St.
NW17-125
Cambridge, MA
02139
phone: 617.253.5401
fax: 617.253.0627
email: jliptac@mit.edu

I am a doctoral candidate in plasma physics working on the Alcator project at MIT's Plasma Science and Fusion Center. My research focuses on extending potential fusion reactors to steady state operation. I have also become interested in plasma processing and materials.

Education

MIT Massachusetts Institute of Technology
Ph.D. Candidate in Applied Plasma Physics, Expected 2006
Minors: Micro/Nano Materials and Processing, Space Propulsion
UW University of Washington
B.S. Interdisciplinary Engineering, June 2000
Relevant Courses: Electrical Engineering, Aero/Astro, and Physics

Current Research

HXR

Hard X-ray Diagnostic

Designed and fabricated a 32 channel x-ray camera for viewing the fast electron population created through lower hybrid waves. Photons from 20-250 keV are measured using CdZnTe detectors and processed using fast digitization signal processing techniques. The system is highly integrated making use of PCB and SMT technology.
Modeling and Simulation

Modeling and Simulation

Simulations of global performance for advanced tokamak plasmas including transport, wave propagation, wave damping, current drive, wave coupling efficiency. Monte Carlo simulations of neutron and photon transport for radiation shield design.
Plasma Material Interactions

Plasma-Material Interactions

Plasma interactions with Titanium at low temperature including diffusion, hydride formation, and embrittlement. Studied through glow discharge chamber and sample analysis.

Past Research

LDX Studied the use of reflectometry for plasma density profile measurements. Laser/sensor position detection system for the floating coil.
UWPS Assisted in the design and construction of an optical system for a high power laser to produce spectroscopic measurements of plasma temperature and density. Performed atomic line radiation measurements to diagnose plasma mode activity and qualitatively describe performance. Constructed fast switching power supplies for feedback control of equilibrium magnetic field allowing great operational flexibility
UWPS Calibrated neutron bubble detectors to measure alpha particle confinement in fusion devices. Identified key issues invalidating this type of detector for proposed use.

Thesis

Lower Hybrid Modeling and Experiments on Alcator C-Mod, (Abstract)
Lower Hybrid Modeling and Experiments on Alcator C-Mod, (Full Text 14.5 MB)


Papers

J. Liptac et al. Hard X-ray Diagnostic for Lower Hybrid Experiments on Alcator C-Mod, Submitted Rev. Sci. Instrum.

E.S. Marmar et al. Overview of Recent Alcator C-Mod Research, Nucl. Fusion 43, 1610-1618 (2003)
R. K. Fisher et al. Measured Response of Bubble Neutron Detectors and Prospects for Alpha Knock-on Diagnostics, Rev. Sci. Instrum. 72, 796 (2001)

Conferences

American Physical Society, Division of Plasma Physics, Denver, CO, 2005
Modeling of Lower Hybrid Experiments on Alcator C-Mod
High Temperature Plasma Diagnostics, San Diego, CA, 2004
Hard X-Ray Diagnostic for Lower Hybrid Current Drive on Alcator C-Mod
American Physical Society, Division of Plasma Physics, Albuquerque, NM, 2003
Hard X-Ray Diagnostic for Lower Hybrid Current Drive on Alcator C-Mod
American Physical Society, Division of Plasma Physics, Orlando, FL, 2002
AT Scenario Development for Alcator C-Mod Using LHCD
American Physical Society, Division of Plasma Physics, Seattle, WA, 1999
Multi-Point Thomson Scattering Diagnostic for the Helicity Injected Torus
American Physical Society, Division of Plasma Physics, New Orleans, LA, 1998
Measuring the Response of Bubble Neutron Detectors Using DT Accelerators