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DMSP-Geosynchronous Magnetic Conjunctions

We have undertaken a series of studies aimed at testing the global configuration of magnetospheric magnetic field models using a database of observationally- determined magnetic conjunctions between low- and high- altitude satellites. This database, covering a range of magnetospheric activity, local times, and season, has been compiled using four months of plasma electron data from two geosynchronous satellites (1989-046 and 1990-095) and three low- altitude DMSP satellites (F8, F9, and F10). Actual magnetic conjugacy between two of the satellites is determined using the similarity of plasma distribution functions at the two locations as required by Liouville's theorem for distributions along a single flux tube. Since the spectrum at synchronous orbit typically varies slowly with longitude, a single MPA spectrum at the time of conjunction is used for comparison with a number of rapidly- varying spectra from the DMSP auroral zone pass; intervals of close spectral similarity indicate the traversal of the DMSP satellite across the geosynchronous drift shell. More information on this technique and our initial results can be found in Hones et al. [1996; JGR p.2629] and Weiss et al. [1997, JGR, in press].

The format of the file is as follows:
dmsp_id F8, F9, or F10
geo_id 1989-046 (46) or 1990-095 (95)
t0 time of best spectral match
t1 start time of spectral matching
t2 stop time of spectral matching
geo_lat geocentric latitude of geosynchronous satellite
geo_long longitude of satellite
geo_rad radius of satellite
t0_dmsplat latitude at time of best spectral match
t0_dmsplong longitude at best match
t0_dmsprad radius at best match
t1_dmsplat latitude at start of spectral match
t1_dmsplong longitude at start of match
t2_dmsplat latitude at end of spectral match
t2_dmsplong longitude at end of match

Download the database(tab-delimited text file).

NOTE:   Technology and Software Publicly Available

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Questions? Mail Loretta Weiss (lweiss@lanl.gov).
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