William C. Feldman Personal/Professional Page

The Mars Odyssey Neutron Spectrometer (MONS) was launched aboard Mars Odyssey in April, 2001 and has been orbiting Mars in a mapping orbit from about 22 February 2002 to the present.  The spectrometer contains four borated plastic scintillator prisms, each pointing in different directions relative to the spacecraft velocity vector.  Prism 1 faces down toward Mars at 90 degrees to the spacecraft velocity vector and is covered by Cd so that it responds only to epithermal and fast neutrons, Prism 4 faces backward relative to the spacecraft velocity vector and so responds mainly to epithermal neutrons because thermal neutrons from Mars cannot catch up to the sensor, Prism 2 faces forward along the spacecraft velocity vector and so responds mainly to thermal and epithermal neutrons, and Prism 3 faces away from Mars at 90 degrees to the spacecraft velocity vector and so responds mainly to background neutrons.  At the present time we only have the time series of Prism 4 data from 22 February 2002 through 2013 archived at PSI.  The code used to reduce the measured binary data to thermal, epithermal, and fast neutron fluxes was written and run by Sylvestre Maurice at (sylvestre.maurice [at] irap.omp.eu) [S. Maurice, W. Feldman, B. Diez, O. Gasnault, D.J. Lawrence, A. Pathare, T. Prettyman, Mars Odyssey neutron data: 1. Data processing and models of water-equivalent-hydrogen distribution, Journal of Geophysical Research, 116, E11008, doi:10.1029/2011JE003810, 2011].  This time series is now stored on a computer at PSI.edu.  It will be open to free use by anyone by contacting Bill Feldman at feldman [at] psi.edu.  E-mail Bill for the password and then click on the link below.