CIAO "Watch Out" Page

WHAT'S NEW | WATCH OUT

This page lists noteworthy items and issues about the CIAO 4.4 release. For the full list of known issues please review the:

Installing & Starting CIAO | Analysis

Installing & Starting CIAO

Parameter file conflicts with HEAsoft

Both CIAO and FTOOLS use parameter files to store parameter values for tools, and provide tools for manipulating these files (e.g. plist, pset, punlearn; they have the same name in both systems). The location of the parameter files is taken from the $PFILES environment variables for CIAO and FTOOLS (or $UPARM if $PFILES does not exist).

Common errors are:

pget: could not get parameter "foo"

and

The following parameter:
    "foo,b,l,no,,,"Keyword""
has the following error(s):
  o Mode field "l" is invalid.

and

The following parameter:
"foo,i,h,INDEF,INDEF,INDEF,"description""
has the following error(s):
o Problem converting minimum field "INDEF" to parameter type "i".
o Problem converting maximum field "INDEF" to parameter type "i".

We recommend that you start FTOOLS before CIAO to minimize conflicts; more information on this problem is available in the CIAO and FTOOLS section of the Starting CIAO thread. Also refer to the related FAQ "The tool is failing because ")sval" has somehow shown up in the parameter value.".

Conflicts with Other Software Packages

There are some known conflicts between CIAO and other software or system libraries and tools. Issues not covered in this "Watch Out" page are listed on the "Other Software Packages" bug page.

Analysis

CTI_APP Header Keyword is Required

CIAO requires that ACIS event files have a CTI_APP header keyword to indicate whether the CTI correction has been applied. The older CTI_CORR keyword is no longer used.

Follow the instructions in the ACIS CTI_APP Keyword Required section of the ACIS CTI Correction why topic to learn how to check for the keyword and add it if it is missing.

The analysis may produce incorrect results without issuing an error if the keyword is missing.

Specifying Aspect Solution Files

The aspect solution files (pcad..._asol1.fits) are used as inputs to several of the CIAO tools - e.g. acis_process_events, asphist, and tg_resolve_events.

If there is a single aspect solution file, it can be provided directly to the tool:

unix% pset asphist infile=pcadf245733620N002_asol1.fits

In many cases, there will be more than one aspect solution file for an observation. Then all the files must be provided in chronological order. (The time is in the filename, so "ls" lists them in chronological order.) This may be done as a comma-separated list:

unix% pset asphist infile="pcadf063874624N002_asol1.fits,pcadf063875522N002_asol1.fits,pcadf063902942N002_asol1.fits"

The list of aspect solution files may also be given as a stack. Any number of files can be specified in the stack, one:

unix% cat pcad_asol1.lis
pcadf245733620N002_asol1.fits

unix% pset asphist infile=@pcad_asol1.lis

or more than one:

unix% cat pcad_asol1.lis
pcadf063874624N002_asol1.fits
pcadf063875522N002_asol1.fits
pcadf063902942N002_asol1.fits

unix% pset asphist infile=@pcad_asol1.lis

Note that an at symbol ("@") is used before the filename to indicate that it is a stack file.

Incorrect GTIs when time-filtering grating data with dmcopy opt=all

When a time filter is applied to a level=1.5 (evt1a.fits) or level=2 (evt2.fits) grating file and the dmcopy opt=all option is used, the GTI block in the output file is not updated to reflect the correct time range. Time-related header keyword values - such as ontime, livetime, and exposure - will be incorrect because they are calculated from the time ranges in the GTI block.

This time-filtering is one of the standard reprocessing steps for grating data, so anyone that reprocesses a grating dataset in CIAO 4.4 is affected.

This bug affects all ACIS and HRC grating data analysis. Read the bug report for details and a workaround.