SAS watchout page
In this page some issues concerning SAS and XMM-Newton data analysis
are reported, along with recommended workarounds and/or solutions,
and useful tricks and tips.
Many of the items below are extracted from the
SAS
HelpDesk questions database, and frequently updated.
If a SAS topic of interest is not reported in this page,
users are invited to search in the HelpDesk database before submitting an
Observation Report
or contacting the XMM-Newton
HelpDesk.
SAS 7.0.0
- Is it true that lccorr is unreliable? --
Answer
- Artifacts in XMM-Newton time series analysis? --
Answer
- There is no labelling of the axes in the rgsimplot output. Why? --
Answer
- Why is the BACKSCAL value wrong in TIMING mode? --
Answer
- On-line documentation on rgsproc and rgsregions
parameters xpsfincl, xpsfexcl and pdistinc
default values differs from their tasks default values. What is
correct? --
Answer
- On RHEL 4 update 4, omichain (and omfchain)
fail to run properly due to a changed version of
ghostscript. --
Answer
SAS 6.5.0
- I cannot filter on the TIME an RGS event file produced with a former
SAS version. What am I doing wrong? --
Answer
- Why does "atthkgen" fail due to "time correlation" related problems,
working with the MacOS version of SAS? --
Answer
- Quadrant in PN with fewer events than expected? ? --
Answer
- Is it safe to use SAS 6.5 under a Mac OSX 10.4 (Tiger)? --
Answer
- What is about the patch to SAS 6.5? Do I need new calibration files? --
Answer
- Why do I get the error "UnsupportedAlgoId" when processing MOS data? --
Answer
- Can I use my old scripts in SASv6.5, which include calls to
the very much refurbished emproc / epproc? --
Answer
- I get a segmentation fault when trying to run rgssuperrmf.
Am I doing something wrong? --
Answer
SAS 6.1.0
- Why do I get bad MOS spectral fits now using SAS 6.0 and SAS 6.1? --
Answer
- Can I use SASv6.1 with any processed event lists? --
Answer
- Reprocessing pn data with SASv6.1 yields event lists with less
photons than with SASv5.4.1. Am I doing something wrong? --
Answer
- Bug in tabgtigen --
Answer
- My BACKSCAL (or effective area) has crazy values: help! --
Answer
- Can I use
arfgen for spectra extracted from regions of
arbitrary shape? -- Answer
- I get the error: "Subscript 1 of PATTFRACTION (value 1) is
out of range (1:0)" with
rmfgen --
Answer
- My exposure maps are identically null everywhere. Am I doing
something wrong? -- Answer
- How far can I trust the results of my timing analysis? --
Answer
- The OM chains fail saying that an OM
exposure mode is "UNDEFINED" in the ODF. However, ... --
Answer
SciSim
- Is the outcome of SciSim (V4.0) really a realistic representation of
science data obtained with XMM-Newon? --
Answer
ODF
- Why does it take so long to produce an ODF? --
Answer
PPS products
- How do I know which CCF were used to reduce my
event list? --
Answer
- I do not find EPIC (or OM) processed data in my PIPEPROD
directory. Did something go wrong with the pipeline processing? --
Answer
Evergreen tips and tricks
- How can I correct for time sensitivity degradation of the OM
detector? --
Answer
- These long parameter names are really annoying ... --
Answer
- How do I compare two Calibration Index Files? --
Answer
- How do I calculate the BACKSCAL keyword for my EPIC
spectra? --
Answer
- Can I generate EPIC response matrices with all types of spectral binning? --
Answer
- Are there any differences between "standard" and SAS-generated
EPIC response matrices? --
Answer
- Can I estimate the pile-up level in my observation? --
Answer
- Can I perform the barycentric correction on OM data in Fast Mode? --
Answer
- How can I convert from OM count rates to fluxes? An update --
Answer
- My grace window seems not to start. Is there anything wrong
with the SAS? --
Answer
- Rectangular grace windows: how to get them? --
Answer
Old SAS versions
6.0.0
- I have a problem running
rgsproc, because a library is missing. How can I solve it? --
Answer
- My SunOS workstation cannot run SAS v6.0 due to ``missing libraries'' ... --
Answer
- If I close (Exit) the
xmmselect GUI,
the X display is suddenly restarted. What can I do? --
Answer
- Can I run old SAS scripts with the new SAS v6.0, given its new parameter interface? --
Answer
- Shall I update my calibration files with SASv6.0? --
Answer
- My odfingest run complaints about TimeOutOfRange. Is my ODF healthy? --
Answer
- Are there any software requirements on the analysis of MOS/RGS post-cooling data? --
Answer
- I get an error when processing my pn data with epframes. Any clues? --
Answer
- The coordinates of regions
I import in xmmselect from ds9
are fully out-of-bounds. Am I doing something wrong? --
Answer
- The emission line energies in my MOS spectrum seem a bit too low.
Any calibration issues? --
Answer
- I observe a shift in time between OM and other light curves. --
Answer
5.4.1
- I do not find a SAS v5.4.1 version for Red Hat 7.2 --
Answer
- Running SAS v5.4.1 for Red Hat 7.2, some programs
crash mysteriously. Anything wrong with the SAS? --
Answer
- My SAS seems not to recognize my Red Hat Perl version.
Is there something I can do to tame it? --
Answer
- I have Red Hat 8.0 installed on my workstation. Can I use the SAS? --
Answer
- Does BACKSCAL take into account
all the "blank areas" in a spectrum extraction region? --
Answer
- Can I use evigweight on all types of event lists? --
Answer
5.3.0
- A library error prevents me from running any SAS tasks. What have
I done wrong? --
Answer
- I get a FITSIO or DAL error when I try to read an event list file.
What's happening? --
Answer
- My MOS data get strangely screened by
emproc. Am I doing something wrong? --
Answer
- I am unable to analyze RGS products, created with SAS v5.0, using
later versions of SAS. Is there a workaround? --
Answer
- Are there any incompatibilities between CCF
constituents and SASv5.3.0? --
Answer
- My SAS seems to be inconsistent
with a MOS redistribution CCF. What can I do? --
Answer
- LOW, MEDIUM, HIGH, EXTENDED ...
how do I get "the" EPIC PSF from calview? --
Answer
- ONTIME is much shorter than
the elapsed time. Am I doing something wrong? -- Answer
- xmmselect does not seem to recognize the screening
criteria used to generate a filtered event list --
Answer
- I get strange edge-like features in my pn spectrum. Is therefore
something I need to know? --
Answer
5.2.0
- SAS seems not to recognize the ASCII summary file pointed by
SAS_ODF. Am I doing something wrong? --
Answer
- Good start! odfingest (or cifbuild) complaints that the
summary file does not have the CONFIGURATION record ... --
Answer
- Extracting a scientific product with xmmselect/evselect I get a warning concerning the exposure time. Should I worry? --
Answer
- The circular annulus region in ds9: annulus(x,y,rinner,router) gets imported by xmmselect as annulus(x,y,0,rinner). What is wrong? --
Answer
- rgsproc crashed with an out-of-range error
on betabinning. Is it a bug? --
Answer
Pages maintained by SAS librarian.
Any question about SAS should be addressed to the
XMM-Newton help desk.
Updated on:
May 25, 2007