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This archive documents the numerical results of the paper by Hirt & Kuhn (2017),
JGR - Planets,  JGR Planets 122, doi:10.1002/2017JE005298.
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compiled by Christian Hirt, TU Munich, 02 Aug 2017
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This archive provides data sets used or generated for the publication

Hirt, C. and M. Kuhn (2017), Convergence  and divergence in spherical harmonic 
series of the gravitational field generated by high-resolution planetary 
topography – a case study for the Moon. Journal of Geophysical Research – 
Planets, 122, doi:10.1002/2017JE005298.


What exactly does this archive provide?
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This archive provides 
1) the topographic mass model that defines the gravity field generating masses,
2) the derived gravity field coefficients using spectral forward modelling, and
3) the derived gravity field values using numerical integration techniques.


How is this archive organized?
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1) The spherical harmonic coefficients (SHCs) of the topographic mass model
   are found in folder "InputTopography", stored as binary SHC file (BSHC).
2) The potential SHCs of the gravity field implied by the topographic mass
   model, computed with spectral-domain forward modelling, are found in folder
   "SpectralGravity Models", stored as binary SHC files.
3) The gravity values (gravity disturbances) implied by the topographic mass 
   model, computed with numerical (Newtonian) integration are found in the 
   folder "NewtonianIntegration", stored as binary grid files.

   
Where do I find further information on the files and content?
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Each folder contains a Matlab script with detailed documentation of the data sets
given in the header. Details on the computational procedures are found in the
Hirt and Kuhn (2017) paper.


How can I read the data sets provided?
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That's easy - just download the Matlab scripts provided in the respective folders
and run them. The data is then read into Matlab's memory and ready for further 
analyses and processing.


How is the BSHC-format defined used to store the SHCs?
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SHCs are stored in TU Munich and Curtin University's binary SHC (bshc)-format 
in "double precision". The bshc-format holds the data as follows:

n_min n_max 
C-coefficients ascending in degree, followed by the order,
S-coefficients ascending in degree, followed by the order,

For example, if the maximum degree is degree 3600, then the file contains:

0 3600
C(0,0), C(1,0), C(1,1), C(2,0), C(2,1), ... C(3600,3599), C(3600,3600),
S(0,0), S(1,0), S(1,1), S(2,0), S(2,1), ... S(3600,3599), S(3600,3600).

Tip: Use the provided Matlab-function read_SHCs_binary_bshc_format2014 to 
read the coefficients hassle-free.