sas radar science highlights

NAIC Visiting Committee MeetingFebruary 15-16, 2005

SAS Radar Science HighlightsOutline:

– And finally describe the aeronomy and radar school from last summer.

– We also discuss progress in meeting some of our challenges with our aging hardware, in particular, the 430 MHz transmitter, and the digital receiver, which will replace many old analog components .

– We discuss progress (results) in meeting this goal, and show how our improving capabilities ‘spin-off’ into other projects.

– The equivalent talk last year presented one difficult scientific goal, and then showed how improvements in our science program would allow it to be achieved, involving staff, hardware, and techniques, or people, tools, and ideas in current NSF language, and this year…..

– We look at staff and budget issues.

– HF Facility: proposal will be withdrawn, resubmitted; talk later in day


Staff Issues (SAS in general)

• SAS staff:Sixto, Mike, Craig, Nestor, Jose, Hein, Shikah, Ryan• Coming: Johannes, Paloma• NSF Funded users: John Mathews, John Noto, Xin Shao, Diego

Janches, Lara Waldrop• Students: Romina Nikoukar, Mike Nicolls


Budget Issues

• EAS initiative moves to Jicamarca budget. (little practical significance)

• FY 2006 will bring a small cut in the SAAS budget from NSF UAF.


Our Goal: Routine Molecular ion Measurements in the World Day

Periods

– Both ion and plasma line measurements required (Day time only technique)

– New ion line technique with modern inverse technique– New amplitude codes for reducing statistical errors added by

inversion– Optimization of these codes still under way– Coded long pulse technique for plasma line: computations on cluster– Simultaneous dual NLLS fitting technique after inversion of ion line– It must be all put together into a practical, standard technique.


Plasma Line Measurement


Measuring F1 region ion composition and temperatures with plasma line and ion line data at Arecibo

Nestor Aponte, Michael P. Sulzer, Romina Nikoukar, Michael J. Nicolls and

Sixto A. Gonzalez


Combination of ion line and plasma line


Arecibo April 3, 2004 at 14:52


Spin-off Effects


The MIT Experiment

• Min Chang Lee and Students have been looking for the interaction of guided whistler waves with the ionospheric plasma using a variety of diaagnostics.

• One of these is the ionospheric plasma line (enhanced, at night).• The availability of the coded long pulse experiment, recording raw

data for later analysis, has allowed a group of MIT undergraduates working with Professor Lee to take data and AO analysis software back to MIT.

• They have found a surprising night time E region plasma line associated with sporadic E.

• (I have repeated their analysis and see it also.)• This potential result requires careful verification, but the

characteristics of the CLP technique make “false” observations of this kind unlikely.


Transmitter Discussion Points

• Although we have lost a significant amount of time in the last year due to problems with the 430 MHz transmitter, most of these problems are solved, or the solution is underway.

• Limitation in average power due to high body current (since the new type of Klystron was installed) have been solved with the correct magnet current tuning procedure.

• We have had some power monitoring problems. The upstairs power meter now works correctly. The high voltage monitoring resistor tower has been replaced, but this is probably not the permanent solution.

• 4-400A tubes in the modulator are checked and replaced more frequently; they seem to be “life-time challenged”.


New Digital Receiver• Plot of Ryan’s first power profile goes here with a disucssiom of the

status.


Arecibo PARS Summer School

• Description and pictures

sas radar science highlights

Documents

plasma line measurements

ion line data

ionospheric plasma line

plasma linearecibo

standard technique

clp technique

inversion of ion lineit

world day periodsboth