RPS - Preparation

Use the Define Deadtime OR Livetime Parameters option (RPSFILT GX) to perform instrument deadtime corrections on airborne radiometric data. You can also use this dialog to apply a low pass filter to the radiometric and/or barometric altimeter data and correct the altimeter data to Standard Temperature and Pressure (STP).

Raw radiometric data in RAW channels are filtered and placed in FILT channels. To display filtered data, look for the channels that have FILT included in the channel name.

Define Deadtime OR Livetime Parameters dialog options

This is the first of two dialogs. Use this dialog to choose the method (i.e. deadtime or livetime) and to enter the instrument correction and to select the livetime channel.

Choose Deadtime or Livetime method from list	Select the method from the list.
INSTRUMENT DEADTIME (microseconds/pulse)	The instrument deadtime (microseconds/pulse) The deadtime value is preset to 0 meaning that the correction is not applied. If you want to see the effect of deadtime corrections on the dataset, try entering another value (in microseconds).
INSTRUMENT LIVETIME CHANNEL (milliseconds)	Select the instrument livetime channel.

Define Optional Low pass Filter Values dialog values

This is the second of two dialogs. Use this dialog to enter the filter values for cosmic, total count, potassium, uranium, thorium and the radar altimeter.

COSMIC:	LP Short Wavelength Cutoff (fiducials) (Default is 35.0)
TOTAL COUNT:	LP Short Wavelength Cutoff (fiducials) (Default is 4.0)
POTASSIUM:	LP Short Wavelength Cutoff (fiducials) (Default is 5.0)
URANIUM:	LP Short Wavelength Cutoff (fiducials) (Default is 7.0)
THORIUM:	LP Short Wavelength Cutoff (fiducials) (Default is 7.0)
RADAR ALTIMETER:	LP Short Wavelength Cutoff (fiducials) ( Default is 5.0)

Application Notes

This RPS Preparation dialog runs three processes -- deadtime correction,filter and altimeter correction. You must supply values for the first two processes. The last process is automatic.

By default, the low pass filter high frequency values are set from 4 –7 except for the Cosmic channel which is set to 35.0 for heavier filtering.

When you are finished setting all parameters, press OK. Once processing completes, we suggest that you compare the raw and filtered data (FILT channels) in the profile window. If you are not satisfied with the initial results, rerun the Preparation dialog and change the parameter values.

Additional Script Parameters

URAW	Input U Channel Name
KRAW	Input K Channel Name
THRAW	Input TH Channel Name
TCRAW	Input TCount Channel Name
COSRAW	Input COSmic Channel Name
BALTRAW	Input BALT Channel Name
RALTRAW	Input RALT Channel Name
CTEMP	Input Temperature Channel Name
UFILT	Output U Channel Name
KFILT	Output K Channel Name
THFILT	Output TH Channel Name
TCFILT	Output TC Channel Name
COSFILT	Output COS Channel Name
RALTSTP	Output RALT Channel Name
DEADTIME	Equipment Deadtime
LIVETIME	Equipment Livetime Channel
USWAV	Short Wavelength Cutoff for U
KSWAV	Short Wavelength Cutoff for K
THSWAV	Short Wavelength Cutoff for TH
TCSWAV	Short Wavelength Cutoff for TC
COSSWAV	Short Wavelength Cutoff for COS
RALTSWAV	Short Wavelength Cutoff for RALT