# Presentation: 928241

## Status of IMS at GSFC

- By Ed Sittler
- CAPS Team Meeting #28
- Marseille, France
- July 26-28, 2004

## List of GSFC CAPS Team Members

- Ed Sittler
- Don Glenn
- Kevin Edwards
- Sarabjit Bakshi
- David Simpson
- Richard Hartle
- Mark Shappirio
- Dennis Chornay
- Tom Vollmer

## List of Ongoing & Completed Tasks

- Calibration of IMS Prototype
- Ion Beam Measurements at GSFC Cal Facility Completed Feb. 04
- Energy coverage: 64 eV to 15 keV (Vpa = -14.6 kV)
- Ions Measured: H+,H2+, He+,C+,N+,O+,H2O+, Ne+, Ar+, O2+,CO+,CO2+, C2H2+,C2H4+,C2H6+,N2+
- Data stored in Excel Spreadsheets
- Analysis of Cal data using Logistic Power Peak Function of all measured species for E  15 keV. Completed March 04.
- Analysis only includes major fragments (I.e., Neutral, negative, positive peaks). All ghost peaks and tail deferred for later analysis.
- Peak Fit Software used for Analysis. Results stored in Excel spreadsheet.
- Gaussian-Lorenzian should yield better fits. Parametric studies easier. Deferred for later analysis.
- A0 = Probability of Fragment, A1 = Peak Center, A2 = Peak Width, A3 = Peak asymmetry. A2 > 0 asymmetric to larger TOF. A2 < 0 asymmetric to shorter TOF. A3  1. If A3 = 1 peak symmetric and A2 sign undetermined.

## List of Ongoing & Completed Tasks(continued)

- Analysis of Modeled Line Profile Functions. April-May 04
- Determine energy dependence of line profile parameters.
- Allows one to extend line profile parameters to E > 15 keV.
- Used combination of different data sets to measure energy dependence of ion fragments over a wide range of energies. This is especially applicable to LEF data. Allowed us to do ions not measured.
- Assumed molecules immediately broke up when entering c-foil
- Found determination of mass dependence of peaks misleading.
- Diatomic molecules/more complex observe up to 50 kV for LEF.
- Determined probabilities of different fragments.
- Normalized peaks to unity. Pi = 1.0. Pi = A0i.
- Used combination of different ions to do ions we have no data.
- Used FM data to help in their computation for E > 15 kV.
- Used extrapolations to higher energies to compute parameters for higher charged state ions such as He++ and O++.
- Results used to make group tables.
- Results need to be documented in word file. Parameters in Excel file.

## List of Ongoing & Completed Tasks(continued)

- Ion beam measurements of prototype at GSFC High Energy Facility.
- Extend energy of calibration from 15 kV to 50 kV. (Vpa = -14.6 kV).
- Ions Measured: H+,H2+, He+,C+,N+,O+,H2O+, Ne+, Ar+, O2+,CO+,CO2+, C2H2+,C2H4+,C2H6+,N2+.
- Measurements should be completed this week. July 04.
- Data stored in Excel Spreadsheets.
- We will then repeat analysis done for E  15 kV. This analysis will be used to make comparisons with our previous extrapolations. The end result will be revised group tables at higher energies.
- Results of analysis will be stored in Excel Spreadsheets.
- Need to make comparisons with FM cal data and FM Flight Data.
- Sources are: SwRI, LANL, Earth Flyby, Solar Wind, Jupiter & Saturn
- Routine written that will interpolate in energy and return peak parameters for all ion species and their fragments. Used for Group Table Generation.
- Developing IMS Simulator. Includes rate dependent effects. In hold.

## List of Ongoing & Completed Tasks(continued)

- Flight Software Development
- SAM Group Table Generation
- Test plans developed. Used simulations from Sittler et al. (2004) paper. April 04.
- Computed simulated spectra.
- Computed binning intervals and inverse-coupling coefficients.
- Converted simulations into TDC simulator files. Fed into EM System.
- Produced data products
- Wrote simulator code to simulate quick-look displays. Compared with output of EM System and Flight Software. Results documented.
- With results of prototype calibration and its analysis generated Group Tables for SOI, Inner Magnetosphere, Titan Torus and Solar Wind.
- Tested all Group Tables. Repeated above procedures and test plans.
- Delivered Group Tables to SwRI. May 04.

## List of Ongoing & Completed Tasks(continued)

- Hardware Binning versus Software Binning.
- Present version of hardware binning too slow.
- Revised version will be very fast and allow one to handle more complex situations. 15 ion sub-groups possible.
- Will be more accurate.
- In order for software binning to run fast enough must collapse data by factor of 4 for ST and factor of 2 for LEF.
- Use full 2048 channel capability.
- Binning intervals can have wider widths and still run fast.
- Multiple binning intervals now possible. Increase accuracy and improve statistics. (I.e., bin on O0 and O- peaks).
- Other flight software issues being worked on as time allows.
- Support operations, which includes present analysis of SOI data.

## List of Ongoing & Completed Tasks(continued)

- Analysis of SOI Data.
- Developed read routines so we can read level0 data products in order to evaluate performance of flight software, SAM Algorithm, Group Tables, Quality of Data Products and Comparison with level2 data products.
- SwRI to provide level2 data product read routines.
- Concentrating on June 30 18:00 to 24:00 hours data.
- We have ability to analyze all IMS data products.
- TOF Spectrograms for internal analysis of data.
- Ion data products. Evaluate performance of SAM.
- Statistical fluctuations cause water group ions to anti-correlate.
- Summing of water group ions removes this structure. Nice energy plots.
- Have capability to deal with C-kernels, S/C orientation/actuator angle.
- Can perform pitch angle analysis of data. Presently use Connerney Model.
- Can perform trajectory plots and field line mapping.
- Presently developing algorithm to perform non-linear fits to TOF data.
- Analysis gives relative abundance of ion species & investigate ion shifts.
- Determine ion composition.

## List of Ongoing & Completed Tasks(continued)

- Developed script routine to capture more data.
- RTIU? problem is causing us to throw out a majority of the data.
- Present routine has problems and some bad data not excluded.
- Will continue to work problem.
- Developing algorithm that will re-construct ion counts from ion data for previously determined ion peak shifts and other calibration determinations from analysis of TOF data. Algorithm requires high rate data (4,8,16 kbps)
- With revised cal data compute ion data products for all combinations of ion counts, energies and presently used Group Tables.
- Then using a multi-dimensional interpolation routine compute the reconstructed ion counts from the measured ion counts using a non-linear fitting algorithm. The first step will make algorithm fast.
- This algorithm should provide more reliable composition results.
- Once the above completed will be able to compute fluid parameters for various ion species.
- The results of the above analysis will allow us to make more accurate group tables.