KPL/IK MAVEN SWIA Instrument Kernel =============================================================================== This Instrument Kernel (IK) file contains parameters for MAVEN SWIA instrument. Version and Date ------------------------------------------------------------------------------- Version 1.0 -- January 13, 2014 -- Jasper Halekas, MAVEN P&F Team References ------------------------------------------------------------------------------- 1. Kernel Pool Required Reading 2. GETFOV, getfoc_c, cspice_getfov headers 3. MAVEN FK file, latest version 4. Contact Information ------------------------------------------------------------------------------- Jasper Halekas, MAVEN P&F Team, 510-643-4310, jazzman@ssl.berkeley.edu Implementation Notes ------------------------------------------------------------------------------- This file is used by the SPICE system as follows: programs that make use of this kernel must ``load'' the kernel, normally during program initialization. The SPICE routine FURNSH loads a kernel file into the pool as shown below. CALL FURNSH ( 'frame_kernel_name; ) -- FORTRAN furnsh_c ( "frame_kernel_name" ); -- C cspice_furnsh, frame_kernel_name -- IDL cspice_furnsh( 'frame_kernel_name' ) -- MATLAB Once the file has been loaded, the SPICE routine GETFOV (getfov_c in C, cspice_getfov in IDL and MATLAB) can be used to retrieve FOV parameters for a given instrument or structure. This file was created and may be updated with a text editor or word processor. Naming Conventions ---------------------------------------------------------- All names referencing values in this IK file start with the characters `INS' followed by the NAIF MAVEN ID number (-202) followed by a NAIF three digit ID code for SWIA or one of its detectors or components. This is the full list of names and IDs described by this IK file: MAVEN_SWIA_BASE -202140 MAVEN_SWIA -202141 MAVEN_SWIA_SWTSPOT -202142 MAVEN_SWIA_FRONT -202143 MAVEN_SWIA_BACK -202144 The remainder of the keyword name is an underscore character followed by the unique name of the data item. For example, the -202142 boresight direction provided as a part of its FOV definition is specified by: INS-202142_BORESIGHT The upper bound on the length of the name of any data item is 32 characters. If the same item is included in more than one file, or if the same item appears more than once within a single file, the latest value supersedes any earlier values. Mounting Alignment -------------------------------------------------------- Refer to the latest version of the MAVEN Frames Definition Kernel (FK) [3] for the MAVEN structures reference frame definitions and mounting alignment information. Instrument Description --------------------------------------------------------- The Solar Wind Ion Analyzer (SWIA) is an electrostatic analyzer that measures energy per charge of incident solar wind ions with a nominal field of view of 360 degrees (covered by 24 anodes) by 90 degrees (covered by electrostatic deflection). The undeflected field of view lies in the spacecraft X-Z plane, which is the SWIA X-Y plane. The sunward direction (spacecraft Z, SWIA X) is covered by 10 4.5 degree anodes, and the rest of the field of view is covered by 14 22.5 degree anodes. The energy range is ~5-25000 eV. For energies up to ~4.75 keV, deflection covers the full 90 degree angular range; however, for energies above this threshold, angular coverage is proportionally reduced. As a result, since the angular coverage is energy-dependent, we do not define individual look angles in this kernel, but instead define them in the level 2 data files. Instrument Detector/Sensor Layout (if applicable) ---------------------------------------------------------- 24 anodes cover look directions in the spacecraft X-Z plane (SWIA X-Y plane), with 10 4.5 degree anodes around the sun direction, and 14 22.5 degree anodes covering the rest of the 360 degrees. Deflection allows us to cover angles up to 45 degrees in either direction from this 2-d FOV. The field of view covered by the 10 small anodes is defined as the "Sweet Spot". Instrument Pixel-to-3D Coordinate Mapping (if applicable) ---------------------------------------------------------- Defined in level 2 data files, since this is energy-dependent, and also depends on the sweep table loaded in the instrument. Instrument Detector/Sensor Parameters (if applicable) ---------------------------------------------------------- Defined in the level 2 data files. Instrument Optical Parameters (if applicable) ---------------------------------------------------------- N/A Instrument Optical Distortion (if applicable) ---------------------------------------------------------- N/A Instrument Filter Parameters (if applicable) ---------------------------------------------------------- N/A Instrument FOV Definition(s) ---------------------------------------------------------- This section defines the following FOVs: ID SHAPE FRAME SIZE1 SIZE2 BSIGHT ------- -------- --------------------- ----- ----- ------ -202142 POLYGON MAVEN_SWIA 45. 90. +X -202143 POLYGON MAVEN_SWIA 179.9 90. +X (*) -202144 POLYGON MAVEN_SWIA 179.9 90. -X (*) The FOVs are defined in this data block. The sweet spot is defined as a polygon. (*) The front-looking and rear-looking FOVs are defined as polygons. There is a very small portion (~0.2 deg) not contained in either of these FOV; however, that FOV is blocked by the solar panel and mounting foot of the instrument anyway. \begindata INS-202142_FOV_SHAPE = 'POLYGON' INS-202142_FOV_FRAME = 'MAVEN_SWIA' INS-202142_BORESIGHT = ( 1.0, 0.0, 0.0 ) INS-202142_FOV_BOUNDARY = ( 0.653281 0.270598 0.707107 0.679471 0.195752 0.707107 0.697116 0.118445 0.707107 0.705994 0.0396478 0.707107 0.705994 -0.0396478 0.707107 0.697116 -0.118445 0.707107 0.679471 -0.195752 0.707107 0.653281 -0.270598 0.707107 0.653281 -0.270598 -0.707107 0.679471 -0.195752 -0.707107 0.697116 -0.118445 -0.707107 0.705994 -0.0396478 -0.707107 0.705994 0.0396478 -0.707107 0.697116 0.118445 -0.707107 0.679471 0.195752 -0.707107 0.653281 0.270598 -0.707107 ) INS-202143_FOV_SHAPE = 'POLYGON' INS-202143_FOV_FRAME = 'MAVEN_SWIA' INS-202143_BORESIGHT = ( 1.0, 0.0, 0.0 ) INS-202143_FOV_BOUNDARY = ( 0.00000 0.707107 0.707107 0.146935 0.691672 0.707107 0.287456 0.646041 0.707107 0.415427 0.572206 0.707107 0.525262 0.473391 0.707107 0.612167 0.353910 0.707107 0.672346 0.218977 0.707107 0.703173 0.0744855 0.707107 0.703302 -0.0732583 0.707107 0.672727 -0.217804 0.707107 0.612783 -0.352841 0.707107 0.526088 -0.472474 0.707107 0.416425 -0.571481 0.707107 0.288583 -0.645538 0.707107 0.148142 -0.691414 0.707107 0.00123403 -0.707106 0.707107 0.00123403 -0.707106 -0.707107 0.148142 -0.691414 -0.707107 0.288583 -0.645538 -0.707107 0.416425 -0.571481 -0.707107 0.526088 -0.472474 -0.707107 0.612783 -0.352841 -0.707107 0.672727 -0.217804 -0.707107 0.703302 -0.0732583 -0.707107 0.703173 0.0744855 -0.707107 0.672346 0.218977 -0.707107 0.612167 0.353910 -0.707107 0.525262 0.473391 -0.707107 0.415427 0.572206 -0.707107 0.287456 0.646041 -0.707107 0.146935 0.691672 -0.707107 0.00000 0.707107 -0.707107 ) INS-202144_FOV_SHAPE = 'POLYGON' INS-202144_FOV_FRAME = 'MAVEN_SWIA' INS-202144_BORESIGHT = ( -1.0, 0.0, 0.0 ) INS-202144_FOV_BOUNDARY = ( -0.00123439 -0.707106 0.707107 -0.148142 -0.691414 0.707107 -0.288583 -0.645538 0.707107 -0.416425 -0.571481 0.707107 -0.526088 -0.472474 0.707107 -0.612783 -0.352841 0.707107 -0.672727 -0.217804 0.707107 -0.703302 -0.0732583 0.707107 -0.703173 0.0744855 0.707107 -0.672346 0.218977 0.707107 -0.612167 0.353910 0.707107 -0.525263 0.473391 0.707107 -0.415427 0.572206 0.707107 -0.287456 0.646041 0.707107 -0.146935 0.691672 0.707107 0.00000 0.707107 0.707107 0.00000 0.707107 -0.707107 -0.146935 0.691672 -0.707107 -0.287456 0.646041 -0.707107 -0.415427 0.572206 -0.707107 -0.525263 0.473391 -0.707107 -0.612167 0.353910 -0.707107 -0.672346 0.218977 -0.707107 -0.703173 0.0744855 -0.707107 -0.703302 -0.0732583 -0.707107 -0.672727 -0.217804 -0.707107 -0.612783 -0.352841 -0.707107 -0.526088 -0.472474 -0.707107 -0.416425 -0.571481 -0.707107 -0.288583 -0.645538 -0.707107 -0.148142 -0.691414 -0.707107 -0.00123439 -0.707106 -0.707107 ) \begintext End of the IK file.