KPL/IK XSM Instrument kernel =========================================================================== This instrument kernel (I-kernel) contains CHANDRAYAAN-1 X-ray Solar Monitor (XSM) FOV parameters. Version and Date --------------------------------------------------------------------------- Version 1.0 -- Oct 1, 2008 -- Shyama.K.C SAID/ISAC References --------------------------------------------------------------------------- 1.) http://spice.nasa.gov.in/pub/ 2.) SPICE Training class notes Dec 11-13 2007 3.) Chandrayaan1 Xray Spectrometer (C1XS) – Instrument Design & Technical Details 2008, submitted to PSS Contact Information --------------------------------------------------------------------------- Shyama Narendranath.K.C, SAID/ISAC, 91-80-25083708, kcshyama@isac.gov.in Chris Howe, STFC,RAL,UK Implementation Notes --------------------------------------------------------------------------- Applications that need SPICE I-kernel data must ``load'' the I-kernel file, normally during program initialization. CALL FURNSH ('CH1_XSM_V01.TI') Loading the kernel using the SPICELIB routine FURNSH causes the data items and their associated values present in the kernel to become associated with a data structure called the ``kernel pool''. The application program may then obtain the value(s) for any IK data item using the SPICELIB routines GDPOOL, GIPOOL, GCPOOL. Routine GETFOV may also be used if the file contains instrument field-of-view (FOV) specifications. CALL GDPOOL (NAME, START, ROOM,N, VALUES, FOUND) CALL GETFOV (INSTID, ROOM, SHAPE, FRAME, BSIGHT, N, BOUNDS) This file was created with, and can be updated with, a text editor. Conventions for Specifying Data --------------------------------------------------------------------------- ta items are specified using ``keyword=value'' assignments [1]. All keywords referencing values in this I-kernel start with the characters `INS' followed by the NAIF CHANDRAYAAN-1 instrument ID code, constructed using the spacecraft ID number, -86, followed by the NAIF three digit ID number for XSM instrument base (410). These IDs are Instrument name ID -------------------- ------- CH1_XSM -86410 The maximum length of the keyword must be less than 32 characters. Keywords are case sensitive. If a keyword is included in more then one file, or if the same keyword appears more than once within a single file, the last assignment supersedes any earlier assignments. Instrument Overview --------------------------------------------------------------------------- The X-ray solar monitor (XSM) is part of the C1XS experiment to measure Solar X-ray spectra. It consists of a Si-PIN detector mounted on the upper deck of the S/C at an angle of 45 degree to the deck. The position of XSM on the S/C ensures maximum visibility of the Sun while in the lunar orbit. The electronics of the XSM consists of 1) pre-amplifier stages and shaping amplifier, which are in the sensor unit box and 2) an electronics board in the main D-CIXS instrument box, which includes further stages of the signal processing electronics. The electrical and data interfaces connect the XSM with the C1XS. There will be no direct electrical or data interfaces from the XSM to the spacecraft. Mounting Alignment --------------------------------------------------------------------------- Refer to the latest version of the CHANDRAYAAN-1 Frames Definition Kernel (FK) for the C1XS/XSM reference frame definitions and mounting alignment information. Field-of-View Layout --------------------------------------------------------------------------- This section illustrates the FOV of the XSM detector with respect to the XSM instrument. The computations required to obtain the FOV are also described here. XSM is a single crystal detector, i.e. composed of 1 single pixel. The detector is circular having a diameter of xx mm. The collimating aperture is also circular, with a diameter of 0.35mm. The distance between the collimating aperture and detector is xx mm. |<----- 4.7 mm ----->| | | | | ==`. FoV .'==----- || `. .-. .' || ^ || `. ' ` .' || | Distance between collimating || `. .' || H= 2.00 mm aperture and detector pixel || `.' || | || .' `. || v |`====!.' `.!===='|----- `=====|=========|=====' |=========| |<-0.35 mm->| D/2 + d/2 FoV = 2 x ATAN(-------------- ) = 103.56 degrees. H This diagram illustrates the XSM FOV layout in the XSM reference frame. ^ +Xxsm | | --- .__|__. ^ .' | `. | / | \ | . | . | ~104 deg | x-------------> +Yxsm | . +Zxsm . | \ / v `. .' --- ` --- ' | ~104 deg | Boresight (+Z axis) |<----------->| is into the page | | O FOV Definitions --------------------------------------------------------------------------- This section contains assignments defining the FOV. These definitions are based on the XSM detector and optics parameters provided in this section, along with the previous section and are provided in a format consistent with/required by the SPICE (CSPICE) function GETFOV (getfov_c). The XSM FOV is defined as a cone with a half angle of 51.8924 degrees. It is defined with respect to the SMART1_XSM frame. The boresight vector is a unit vector along the +Z axis of the frame and the cross-reference vector is a unit vector along the +X axis the frame. \begindata INS-238700_FOV_FRAME = 'CH1_XSM' INS-238700_FOV_SHAPE = 'CIRCLE' INS-238700_BORESIGHT = ( 0.0 0.0 1.0 ) INS-238700_FOV_CLASS_SPEC = 'ANGLES' INS-238700_FOV_REF_VECTOR = ( 1.0 0.0 0.0 ) INS-238700_FOV_REF_ANGLE = ( 51.78 ) INS-238700_FOV_CROSS_ANGLE = ( 51.78 ) INS-238700_FOV_ANGLE_UNITS = 'DEGREES' \begintext Platform ID --------------------------------------------------------------------------- This number is the NAIF instrument ID of the platform on which the instrument is mounted. XSM is mounted directly on the spacecraft. \begindata INS-238700_PLATFORM_ID = ( -86000 ) \begintext