PHT32 (Multi-Filter, Spatially Oversampled Mapping Mode with a PHT-C Array Detector)

								   (July 4, 1995)
PHT32 (Multi-Filter, Spatially Oversampled Mapping Mode with a PHT-C Array Detector)
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Prior to your visit at IPAC, for each target, please prepare the following parameters for 
entry into the PGA:

==> Common Data for All AOTs (explained on a separate sheet).

==> Parameters for All Filters:
o DETECTOR: Select either C100 or C200
    
* NUMBER OF POINTS ALONG EACH LEG:  Number of raster points (or telescope pointings)
                  along the scan direction (i.e., the spacecraft Y-axis) in which a 
                  fixed oversampling factor of 3 is maintained by using the chopper 
                  (cf. Table 11, P72 if ISOPHOT manual).

* NUMBER OF LEGS: Number of the scans in the spacecraft Z-direction in which a variable
                  oversampling factor is maintained by telescope repointing (cf. Table 
		  11, P72 of ISOPHOT manual).

* GUARANTEED OVERSAMPLING: Select one from the on-screen list.  This is the oversampling 
                  factor in the Z-direction.  After one choses this factor, the coverage 
                  factor of a given celestial position is fixed.  In order to achieve this
                  coverage for the inner part of the map, a recommended minimum map size 
                  is given in Table 12, P72 of ISOPHOT manual.

	          Note: The PGA screen displays the size of the whole map/scan region that
                  you have selected.  Make sure that it is large enough to measure the 
                  background on your map/scan edges.

o REPETITION FACTOR (1 or 2): An option for the scan mode only, where 1 = no repetition 
                  and 2 = repeat the scanning in reverse direction for each filter.
	     
o MAP ORIENTATION ON THE SKY:  The angle between the scan direction and the celestial
	          North (measured from N to E, 0 to 179 degrees)

* ORIENTATION TOLERANCE ANGLE (0 to 90 degrees):  You should provide an angle as large 
	          as possible.  The availability of observing opportunity depends 
                  strongly on the tolerance angle as the spacecraft cannot be arbitrarily
	          rotated about its X-axis.  Set this angle to 90 degrees if you do not 
                  care about the map orientation.

==> Parameters for Each Individual Filter:
o FILTER:  Select one from the on-screen list (cf. ISOPHOT manual).

* MAXIMUM UNSATURATED SURFACE BRIGHTNESS:  This is the sum of the maximum expected source 
                  and background surface brightness in units of MJy/sr.  This quantity, 
                  together with other input flux densities, is used to set the detector 
		  dynamic range.

o MINIMUM SURFACE BRIGHTNESS OF THE SOURCE: In MJy/sr.

o MAXIMUM BACKGROUND SURFACE BRIGHTNESS:  In MJy/sr

* S/N:  Leave 0.0 if you want to enter the INTEGRATION TIME below or enter the requested
     minimum signal-to-noise ratio.  This quantity, together with the input flux 
     densities, is used to calculate the target dedicated time (TDT).
            
* INTEGRATION TIME: Leave 0.0 if you have requested a minimum S/N ratio above or enter 
     the requested minimum integration time per "sky position" (ie. time for one chopper
     plateau times the coverage factor, cf. ISOPHOT manual).  Note: for PHT32, there are
     some restrictions on the lower limit of the integration time.  For more information,
     see "Notes on PHT32" on IPAC Local Page on Web.

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