K2 Mass Spectral Data Product

Available for the interval from March 17, 1996 through May 31, 2006


The TIMAS instrument compresses energy-mass-angle data acquired on the spacecraft into a series of data products that are telemetered to the ground. The various data products are described in section 4.1 of the instrument paper. The mass spectral data product consists of 64 mass steps covering the full detector range, for each of 6 large solid angles, for 8 selected energy steps. The data product is accumulated for 2, 4, 8, 16, or 32 spin (6 s) periods. Because of telemetry restrictions only selected data products were telemetered to the ground.

The 6 angular bins cover the full instrumental range and nearly 4pi steradians. Two of the look directions are centered on the spacecraft spin axis. For the first part of the mission, the spin axis was orbit normal and the pitch angles sampled in these look directions are near 90 degrees. The other 4 look directions are in the spin plane. Data are de-spun on board based on the spin rate and time of the "sun pulse". The digital data product provides the center pitch angle of each of the 6 look directions and an estimate of the variation of the pitch angle during the accumulation time

Mass spectral data were the primary data used in the preparation of the following publications:

Browse data

24 hour summary mass spectral data displays are available from a calendar or a date driven interface.

A description of the data presented in these summary plots is available here

Digital Data

files of 24 hours of digital mass spectra data are available on the TIMAS web pages. The data are in NASA's Common Data Format (CDF).

The CDF are described in a CDF skeleton table that includes the following variables:

The following Orbit data are included in the digital files.

The following variables in the digitial files contain no data.


Diagnostic Code

A diagnostic code written in the Interactive Data Language using tplot developed by Davin Larsen at UC Berkeley is available.

The diagnostic code generates both line plots and mass spectra.

Return to TIMAS main page

Prepared by WK (Bill) Peterson, March 19, 2010.