RELEASE NOTES ------------- SPECTRAL : Release notes for XSPEC v9.00 (these are also available on the WWW at http://olegacy.gsfc.nasa.gov/~kaa/xanadu/xspec9.html). 1) New commands abund - Switch the table of Solar abundances used in the plasma emission and photoelectric absorption models. The default is as used in the previous release but there is the option to use newer values. goodness - Calculate a goodness-of-fit for non-background subtracted data using a Monte Carlo method. systematic - Apply a uniform systematic uncertainty to the model. untie - unlink two parameters that have been linked together. weight - change the weighting scheme used in the calculation of chi-squared, the new option is 'gehrels' which uses 1+sqrt(N+0.75), an approximation for small number statistics. 2) New features in existing commands The step command has a new option step best which resets non-stepped parameters to the best-fit after each grid point. The opposite is step current. par1 = par2 + number sets par1 to be equal to par2 plus an additive constant. ignore and notice work with energies if given real numbers in the ranges. Multiple spectra can be stored in the same FITS file and read individually. The command data filenm{N} reads spectrum N in file filenm.pha. Changed behaviour of data command so that data 1 filename does not remove files 2-** but data filename does. model none removes all models. The plots including folded data and model now have the option of showing individual model components folded through the response. This option is enabled by the command "setplot add" and disabled again by "setplot noadd". 3) New models absori - Ionized absorber (from Magdziarz and Zdziarski). ascac - For simultaneous analysis of ASCA spectra with corrections for energy-dependent telescope scattering. cemkl and cevmkl - Power-law emission model using MEKAL code. comptt - Comptonization of Wien law spectrum using Titarchuk's calculations. cp6mkl and cp6vmkl - Sixth-order Chebyshev polynomial emission model using MEKAL code. mekal and vmekal - New version of the MEKA model using Fe L supplied by Liedahl. nteea - Pair plasma model (from Magdziarz and Zdziarski). pexrav - Exponentially cut-off power-law reflected from neutral matter (from Magdziarz and Zdziarski). pexriv - Exponentially cut-off power-law reflected from ionized matter (from Magdziarz and Zdziarski). phabs - Photo-electric absorption using latest relative abundances and cross-sections. plabs - Absorption as a power-law in energy, useful for things like dust. redge - Recombination edge. tita_a - Compton reflection from neutral matter (from Magdziarz and Zdziarski). zvfeabs - Redshifted absorption with variable iron abundance. 4) Changes to existing models The plasma emission models now use relative Solar abundances as set by the abund command. The default is from Anders & Grevesse and the new option is from Feldman. The changes in this new abundance table are as follows : C : 3.63e-4 -> 3.98e-4, N : 1.12e-4 -> 1.00e-4, Ne : 1.23e-4 -> 1.29e-4, Ar : 3.63e-6 -> 4.47e-6, Fe: 4.68e-5 -> 3.24e-5. All absorption models except wabs use the same relative abundances as the plasma emission models as set by the abund command. The bremss, vbremss, and zbremss now have a normalization which is not temperature-dependent. For local models the lmodel.dat file needs an extra line starting with the word "null" than before. See the example file in the release. 5) Table models All table models now use a FITS format. The program ctable converts old format table models into FITS. Multiple table models can be used simultaneously. The Raymond-Smith model now runs off a table in the standard table model FITS format. An etable model reads an additive table model type file and then takes the exponential of the negative of the input. The mtable model now defaults to 1 rather than 0 when there is no tabulated model for part of the response energy range. 6) New features The C-statistic has a new normalization suggested by John Castor which provides a goodness-of-fit. All vectors for a given dataset are plotted in the same colour. XSPEC can be called as a subroutine (through xspec/src/subr/xscmnd.f). Model functions can give a result depending on which file the model is being calculated for. This has meant a change in the subroutine interface, the variable WORKSP has been removed and a new integer IFL has been included - see files in xspec/src/functions for examples. All VMS Fortran structures have been removed from the XSPEC source code. 7) Bug fixes The gain fit command is a little more robust (but should still be used with care). It now handles features in the detector efficiency curve correctly provided that they are included in the arf or no arf is used and only a response matrix is given. There was a minor error when calculating errors on grouped data when both the data and background contained bins with zero counts. The wavelength plots were in /keV rather than /A as claimed. ignore bad now works for arbitrarily many ignore ranges. ******************************************************************************* TIMING : esc - Earth_sun_correction. This task corrects times in a fits file for the time delay Earth_sun. No other corrections are applied. See help (xhelp esc). ROSBary - Apply barycentric correction to rosat data. Changed to read either binary or ASCII fits table for the clock correction. This is also distributed under FTOOLS. See help (xhelp ROSBary). Release Notes for XRONOS 4.02 - new input option for FITS file to select start and stop row - window correctly apply if start window occur before first time in the first file. - fix floating error in the exposure checking for the folding search. ******************************************************************************* IMAGING : getsky - retrieve from SKYVIEW an image from a given position in the sky from available surveys. Release Notes for XIMAGE v2.53 1) New Commands Skyview - Import an image from SKYVIEW using 'getsky' (task in image/tools) Label - Write labels on the display image 2) New Qualifiers cct - It is possible to specify user color table from a file using 'cct/user filename'. The colour table is an ascii file with the 3 columns representative of R, B, and G. The values for each colour ranges from 0 to 1. contour - It is possible to specify contour levels from a file using 'contour/file=filename'. The contous file is an ascii file with one column of values. ra_dec_to_ pixel - It is possible to draw an error circle on a position using 'ra/circle=xx where xx is the radius in arcsec 3) Other changes read command for event table : - Fatal error if the EVENTS extension is not found - Fatal error if either X and Y or DETX or DETY column are not found. The PI, PHA, TIME columns are set to zero if not found. - If GTI extension is not found uses one of the exposure keywords in the header of the EVENTS extension. - Now possible to specify RA and DEC to center the image if created from an event file. saoimage command - write out a fits image rather than a binary file write command - default image is written out as a FITS file.