Reflectometer simulation

2-D Full Wave Reflectometer Simulation
The system was presented by Raffi Nazikian at the Reflectometer Workshop in Garching, Germany on 5/11/05. The software is being developed by Eliot Feibush, Gerrit Kramer, and Ernest Valeo at PPPL. The graphical user interface enables setting up and running simulations of correlation reflectometry in realistic fusion geometry. The interface is designed to enable effective collaboration in reflectometry by enabling non-experts to effectively utilize the advanced simulation capability developed at PPPL.

The Full Wave Reflectometer Simulation Code

Elfresco Launcher
Download and run this launcher program to install Elfresco, 
check for new versions, and run with increased memory.
This Java program also checks for the right version of Java on 
your computer.  Initially it installs the latest version of Elfresco
in the "Elfresco" directory in your home directory.  The launcher
then runs Elfresco with the amount of memory you specify.  
Subsequently, when you run the launcher, it checks to see if a new
version of Elfresco is available.  The current latest version is 
dated 1/28/2011.  The version date is shown in the title bar.
Update information is available from the toolbar menu under
Help-->What's new.

    Elfresco is a web service hosted at the Princeton Plasma Physics Laboratory.  Your computer running the  application must be within or authenticated through the PPL firewall to set up and run a simulation.  You must have a valid PPL computer account.  Authenticated users outside the firewall must also have a certificate stored on the FusionGrid credential server to run the simulation.  Request a certificate.  The certificate will be valid for one year and will remain on the server.  A proxy, valid for 14 days, will be created for you on  the PPL cluster.  Elfresco checks the proxy each time you run a simulation.  If the proxy has expired then you will be prompted for your certificate passphrase.  The status of your credential and proxy is shown in the Credential window.  A green background indicates everything is valid and the simulation will run.  A red background means the simulation will not run.

    The system has several software components that run on different computers, as shown in the Multi-Tier Software Architecture figure below.  The Java user interface typically runs on a user's desktop or notebook computer.  It is portable to Windows XP, Linux, and the Macintosh OS.  The graphical user interface enables the user to set up a simulation and verify the input visually.  This client program sends requests to a Java servlet running on a PPL server.  The servlet processes the request or runs  programs on other PPL machines.  The results are sent back to the GUI for visualization and interaction.  Graphs of the input data and the computed solution are displayed with ElVis graph components. 
An overview of the system is shown in these screenshots.

    The simulation is a 2-D wave propagation code.  It takes an electron density profile as input and simulates a transmitter of different frequencies.    The user defines separate regions for computing the full wave solution and the paraxial area.  Visualization of the cut off frequency guides the user in placing the compute regions and setting the frequency of the transmitter.  The full wave solution is computed and displayed as the intensity of the reflected component.  If the user positions receivers then a correlation graph is produced.  A description of the simulation, 
Two-dimensional simulations of correlation reflectometry in fusion plasmas by E.J. Valeo, G.J. Kramer, and R. Nazikian was published in Plasma Physics Control Fusion 44 (2002) L1- L10.

multitier architecture

Documentation & Presentations

   Description of graphs.
   Interactive features.

   Data Optimization - Marc Osherson, Student Presentation 9/2005

 SIGGRAPH 2006 Research Poster:   Multi-Tier Graphical Web Service   -   Poster slides      Abstract
       All-in-one poster:  Simulating Reflectometry in Plasma

APS-DPP 2006 Poster:  Web Interfaces to Fusion Codes