Experiment Planning

Any domestic or international research may request time to use the MPRL facilities.  The link under “Submit a proposal” describes the process of preparing a short white paper proposal.  Potential users are strongly urged to contact the MPRL research team to discuss experimental plans ahead of submitting a proposal.  Topics covered below include:

  • Experiment duration
  • Typical planning timeline
  • Data management
  • Operational modes

Experiment Duration:
Users may request time for a single experimental run or an extended series of shorter runs.  A User may request a minimum of one week and up to four weeks for a single experimental run.  For an extended series of runs (e.g., 3, 3-week runs over a 12 month period to acquire data for a PhD student dissertation).  Generally, a day or two at the beginning and a day at the end of each experimental run are need for experiment setup / breakdown – depending upon the complexity of the experiment.  

The experiment duration should be carefully considered when planning experiments at high field.  Because of the large inductance of the superconducting coils, the ramping rate of the magnetic field is ~1 Tesla / hour.  In general, experiments are performed in “steps” with the magnetic field being ramped to a particular setting, then held at that setting until all the required measurements are performed, then moving on to the next setting.

Typical planning timeline:

  • At six to eight weeks ahead of a scheduled experiment, there will be a video conference with the User Team to review the proposal and discuss the details of its implementation on the MDPX device.  Detailed information regarding the experiment will be needed (e.g., magnetic field range, vacuum conditions, operating pressures, dust particle sizes, diagnostic requiremetns, etc.)
  • After the conference call, fabrication and/or purchase of additional hardware needed to implement the User experiment.
  • At four weeks ahead of a User experiment, the run days will be confirmed.
  • At two weeks ahead of a User experiment, there will be a final video conference call to confirm the experimental plan.
  • On-site operations typically begin by 9 am each morning and can extend as late as 7  or 8 pm, provided that local staff can be available.  The magnetic field can remain  energized for up to 2 weeks of continuous, steady-state operation.

Data management:
After an experiment is complete, a copy of all data recorded by our diagnostic systems will be given to the user on an external hard drive.  Our laboratory will also retain a copy of the data.  External user experiment data will be considered to be embargoed for a period of 6 months, but users may request an additional 6 months if additional time is needed for data analysis.  After the embargo period, data will be availalbe to researcher that requests a copy.

Operational modes:
There are four possible modes of experimental operations for User experiments.  Each mode requires a increasing level of planning and and local team support.  Users will need to indicate which of these modes they will require.  

Mode 1 or 2 experiments can be proposed by both experimental and theory groups that seek to perform validation experiments.  Mode 3 or 4 experiments have been proposed by plasma physics experimental groups as well as research groups that seek to use the magnetic field capabilities of the MDPX device, but not necessarily perform a plasma physics experiment.  Our group has experience accommodating User experiments at all four levels.

Mode 1: Measurements on MDPX using existing capabilities

  • A proposed experiment would use the existing hardware and diagnostics of the facility to perform an experiment. This could be to investigate a particular phenomenon or characterize a type of particle or plasma behavior at high magnetic field.
  • A typical visit of this type could be between 7 to 14 days – with a half-day for setup and a half-day for shut down.
  • Example: A collaborator wishes to operate the device in a low pressure regime to see how particle transport is affected by laser manipulation at high magnetic field.

Mode 2: Measurements on MDPX using non-invasive tools

  • A proposed experiment would use the plasma and dusty plasma generation systems of the MDPX device, but a collaborator would provide an additional diagnostic system.                                     
  • A visit of this type could be as little as 7 days, but more likely to extend to 14 days depending upon complexity of the diagnostic system. 
  • A day or two would be dedicated to instaling and testing the diagnostic system, followed by research operations over the remaining time.  
  • Example: A collaborator wishes to add a high frame rate microscope system to perform high resolution studies of particle motion in the magnetic field.

Mode 3: Measurements on MDPX requiring configuration changes of the primary vacuum chamber

  • A proposed experiment would require changing something on the interior of the primary octagonal MDPX vacuum chamber – e.g., adding electrodes for particle manipulation, changing particle sizes, adding a in-situ diagnostics, etc.
  • The minimum recommended duration of this type of experiment would be 14 days – depending upon complexity of the modifications and time required to establish a good vacuum. 
  • The additional time is needed to ensure the compatibility and safe operation of the external hardware with the magnetic field.
  • Example: A collaborator wishes to change particles and add additional confinement rings to the MDPX electrode to create multiple trapping regions for dust particles.

Mode 4: Measurements using the MDPX magnet system, but using a different vacuum chamber

  • The primary MDPX vacuum chamber would be exchanged for a User-provided system.
  • This type of experiment would likely require an extended stay of at least 14 days and significant planning beforehand.
  • Within the MPRL, we have currently have three chambers that have bee used within the MDPX magnet system.  These are described in the MPRL Technical Manual.
    • Primary MDPX octagonal chamber
    • Particle growth chamber – 6 inch (150 mm), 6-way cross
    • A 10 inch diameter (25 cm) cylindrical chamber