POLAR TIMAS

H1 and H2 High Resolution Data Products

Available for the interval from March 17, 1996 through December 8, 1998

The TIMAS Science Team has developed a data base of parameters characterizing outflow of energetic H+, O+, He+ and He++ from the Earth's ionosphere.

This data base has been used in the preparation of the following publications:

The contents of this Flow Data Base (FDB) are given in the data base specification.

The data base was supplemented by a boundary specification data base derived from HYDRA electron and ion spectrograms as described in Peterson et al. [2008].

The list of boundary crossing times used by Peterson et al. [2008] is given here. A description of the list format is given here

The FDB data base and associated reading/averaging codes were implemented in C and IDL on Sun Workstations. The daily FDB data files on the Sun Workstations are in binary format. The data base is now available in the platform independent CDF format as described below.


Data base contents in CDF format---po_h1_tim files

The daily FDB data base files have been been converted to CDF files using the architecture of the fdb data base. For each accumulation interval of 2 or 4 spins ( 12 or 24 seconds) data paramter values for H+, O+, He+, and He++ are stored in the same, time ordered, variable arrary. These files were deemed too complex to archive on NASA's CDAWeb.

The data base files follow the naming convention po_h1_tim_yyyymmdd_v01.cdf, where yyyy is the year, mm is the numerical value for the month, and dd is the day. The files are available on line at http://lasp.colorado.edu/timas/data/h1-data/

Several compromises were made in assembling the data base. In particular background subtraction, short averaging intervals and the normally low count rates for minor ions (O+, He+, and He++) lead to many data intervals where the data values reported are not statistically significant. The FDB files therefore contain many diagnostic parameters and data quality flags.

The po_h1_tim CDF Seketon Table documents the variable names, contents, and format of all data, data quality, and data availability flages.

An IDL code that reads and plots po_h1_yyyymmdd_v01.cdf files is available here.


Subset of data base in CDF format compatible with CDAWeb display software---po_h2_tim files

CDAWeb is not set up to work with data parameters (such as fluence or energy flux) for four mass constituents in the same data array, such as those in the po_h1_tim_yyyymmdd_V01.cdf files described above. We have taken the data value arrays for upward directed flux (fluence), energy flux and for other relevant parameters in the po_h1_tim format and broken them into mass specific variables as described in the po_h2_v01 CDF Skeleton Table.

Several compromises were made in assembling the data base. In particular background subtraction, short averaging intervals and the normally low count rates for minor ions (O+, He+, and He++) lead to many data intervals where the data values reported are not statistically significant. The data files therefore contain many diagnostic parameters and data quality flags.

The po_h2_tim CDF Seketon Table documents the variable names, contents, and format of all data, data quality, and data availability flages.

The data base files follow the naming convention po_h2_tim_yyyymmdd_v01.cdf, where yyyy is the year, mm is the numerical value for the month, and dd is the day. The files are available on line at http://lasp.colorado.edu/timas/data/h2-data/

The IDL codes that read in the po_h1_V01 files and created the po_h2_v01 sub-set data files are available here and here. IDL code to read the po_h2_v01 data files and display them is available here.


Prepared by WK (Bill) Peterson, May 2008.