PIA V10.0 - 05/07/2002 ========= CONFIGURATION: -------------- * PIA V10.0 is released in several versions for running on top of IDL 5.0, 5.1/5.2, 5.3, 5.4 and 5.5 respectively. PIA recognizes automatically which savefile has to be loaded. The savefiles contain pre-compiled code for the whole PIA. A special package, the P32Tools, has been added (details under Graphical I/F section). Due to compatibility problems found, this package has not been pre-compiled, but the single routines included in the path, so that they get compiled at the time of execution. HELP & DOCUMENTATION: --------------------- * The PIA Users Manual for 10.0 is not available at the time of the release. As soon as it is available, we will put it under the PIA homepage. * Help pages for the P32Tools package added to PIA are available under [PIA_ROOT]/p32tools/help. The Help button included in the P32Tools GUI is pointing to the pages. GRAPHICAL I/F: -------------- * Under Buffer -> P32Tools the special package for P32 data reduction P32Tools can be started. The package P32Tools (Tuffs & Gabriel 2003, A&A 410, 1075) was originally developed at the Astrophysics Division of the MPI für Kernphysik in Heidelberg. The adaptation of this program to PIA as part of the P32Tools package was coordinated and supported by the ISO Data Centre at VILSPA of the ESA Research and Scientific Support Department. The GUI was developed at the Infrared Processing and Analysis Center at Caltech. * General AOT/Batch processing includes the possibility of switching between difference signals between adjacent read-outs for P32 mode (default) or ramps (which can be also subdivided). See point 1 of PROCESSING section. * The use of robust bi-weight mean calculations can be customized for signal mean calculations: Top level menu > Customize > Biweight means Defaults are: use of bi-weight mean for chopped cases AND no use of it for staring observations. * Default for cases of two FCS measurements for calibration (eg. by maps) has been changed in General AOT/Batch from interpolation to average. See point 7 of PROCESSING section. * Menu for "Define Map Parameters" (called from Mapping main menu) includes the possibility of changing the percentile for a statistical flat fielding ("First Percentile Normalisation") - see point 11 of Processing section. PROCESSING: ---------- It follows a list of upgrades, both including software as calibration files upgrades: 1) Glitch removal for PHT32 observations Similar to the processing for single pointing chopped measurements, the difference signals between adjacent read-outs are used by default rather than the slopes of the complete ramps. The signal per chopper plateau is determined by using the robust bi-weight mean method. 2) Warning of residual drifts in FCS calibration The usual exposure time of FCS measurements is 32s. This is sometimes too short to achieve a stabilized signal. Since the absolute signal of the FCS measurement determines the responsivity and hence the absolute flux calibration, any unstabilized FCS signal has direct impact on the absolute calibration accuracy. In case of unstabilized FCS signals, warning messages are written to the headers of the SPD and AAR products. 3) Further consolidation of flux dependent signal linearization and FCS characterization The linearization tables P%%SLINR were updated. Since linearization curves and FCS power files are linked together, both were updated consistently, i.e. also new CalG tables P%%ILLUM, P%%FCSPOW, P%%FLAT and PPFTOF were generated. 4) Point spread function correction factors New psf factors (CalG files PPPSF and PCPSF) were computed taking a model for the secondary tripod into account. 5) Orbit dependent default responsivities For P3, C100 and C200 the FCS measurement data set was reprocessed using the correct OLP 10 calibration. Linear least median square fits were applied to the data and bootstrapping on 500 data sets per detector and time dependence was performed to derive the uncertainties. The time dependent CalG files PPRESP_01, PPRESP_02, PC1RESP_01, PC1RESP_02, PC2RESP_01, and PC2RESP_02 were revised. 6) Application of default responsivities if FCS power is outside calibrated range In particular for P1, tests showed that more accurate photometry results were achieved when using the default responsivity rather than the extrapolation of the FCS power curves. As soon as the FCS heating power is outside the calibrated range for the respective filter (formerly called "soft limits") , default responsivities are used in calibration. A corresponing message is issued. This holds for staring, absolute, raster and chopped photometry. 7) Application of average responsivities in mapping mode The responsivities are now by default averages of the two FCS measurements, provided both are of good quality. If both are outside the calibrated FCS heating power range, default responsivities are used (see item 6). If only one good FCS measurement is available, this one will be taken. This is particular important for sparse map measurements where the FCS settings can be different. 8) Refinement of signal correction for chopped P2 photometry measurements The asymmetry assumed for P chopped photometry in the so-called pattern analysis (default for chopped photometry) has been taken out. The recommendation is to use default responsivity for this mode. 9) Extension of PHT-S dynamic spectral response calibration to longest exposure times Good quality measurements of 1024 seconds up to 4096 seconds were used for self-calibration in that respect, that the flux was predicted from the first 512 seconds of the measurement, which is based on calibration standards, and transferred to the remaining exposure time. The consistency of the method was checked for the standard star measurements of 1024 seconds. Consequently the conversion factors in the CalG file PSDYNAMIC were updated and the weights in PSDYNWT adapted. 10) Relative intensity profiles for multi-aperture measurements In ESA SP-455 (ISO Beyond Point Sources), page 41, T.G. Mueller described a method how to make scientific use out of multi-aperture measurements (AOT PHT04), provided the source is as compact as 2 arcmin. The background signal is derived from the annulus formed by the 120 and 180 arcsec apertures of the on-source measurement. Therefore, only measurement sequences with these two apertures and at least two smaller ones are processed in this way. The background for all apertures has to be scaled with regard to the 180 arcsec aperture applying non-unity correction factors to the geometrical aperture area ratios. A signal normalized to the one in the 180 arcsec aperture is constructed which is the same as the flux ratio of both apertures. The normalized fluxes are written to the header of the AAR product. In addition source and background signals are written to the header of the SPD product. The aperture correction factors for the background scaling have been hardcoded, no CalG file was generated. ** Implementation into PIA done. To be found under Astrophysical applications > Multi-aperture Photometry 11) Statistical flat-field correction for PHT-C raster maps If the extent of the PHT22 or PHT32 raster map exceeds 20 raster points or plateaux, a statistical flat-field is determined from the ratio of the %10tile of the surface brightness of each pixel to the average %10tile for all pixels. These correction factors are applied to the PGAI products and are written to the product header. ** Percentile for the flat-field correction has been made selectable. BUGS fixed: ----------- There were no bugs reported to V9.1 ******************************************************************************