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Last modified: 28 September 2015

URL: http://cxc.harvard.edu/ciao/releasenotes/ciao_4.0beta2_release.html

CIAO 4.0 Beta 2 Release Notes


[New] (14 Sep 2007) CALDB 3.4.1 has been released.

The CIAO 4.0 Beta 2 release includes a new, more powerful version of ChIPS, the CIAO plotting package. It can be used during data analysis - e.g. to plot a lightcurve - and to create publication-quality figures. Details and documentation on the new system is available from the ChIPS website.

Several bug fixes to the CIAO tools are also included.

Sherpa is not included in CIAO 4.0 Beta 2. It will be released in Beta 3 (Fall 2007).



How CALDB 3.4.1 Affects Your Analysis

This section of the release notes describes how the CALDB 3.4.1 release will affect your analysis. The changes are arranged by instrument and grating configuration.

ACIS Imaging Data

  • Time-dependent ACIS Gain (TGAIN) Files

    There are new time-dependent ACIS Gain (TGAIN) files for 01 May 2007 - 31 July 2007 (Epoch 30):

    acisD2007-02-01t_gainN0005.fits
    acisD2007-02-01t_gainN0006.fits
    acisD2007-05-01t_gainN0002.fits
    acisD2007-05-01t_gain_biN0002.fits
    

    The files are applicable to -120 C data only. The acisD2007-05-01t_gain[_bi]N0002.fits files are the new default proccesing files in the CALDB.

    These plots illustrate the degree of change the new files will produce in comparison with the old files.

    Epoch 30

    In both of the above figures it is apparent that the T_GAIN correction at the I3 aimpoint is diminishing over Epochs 28 - 30.

    In the S3 case, the general trends with energy and Epoch number are the same for the CTI and non-CTI cases by comparison, but with clear differences between them in specific values particularly above 5 keV. This is normal for recent epochs with T_GAIN corrections.

    Users working with ACIS data taken during this period may wish to reprocess to improve the TGAIN calibration in their data. The DATE-OBS header keyword records the observation start date.

    Note that unless you are fitting a spectra with oxygen emission lines, the gain refinement is unlikely to have an effect on the spectrum larger than the uncertainties in determining the gain.

  • ACIS Blank-Sky Background Files

    The newest versions of the ACIS blank-sky background files are now available in the CALDB.

    This set of ACIS background files includes:

    • files for -120 C data on ACIS-5 or ACIS-7 with CTI_APP = PPPPPBPBPP header keyword value (i.e. parallel and serial CTI applied to the back-illuminated chips)

    • CTI-corrected files for ACIS-8 (ACIS-S4).

    • upgrades to the files for chips 1-3, 5-7, and 8 with ACIS-S in the focal plane. These files include the newest CTI and TGAIN corrections.

      The non-CTI-corrected background files for these chips have the TGAIN applied. This matches how observational data at -120 C without the CTI-correction would be processed.

    The Using the ACIS "Blank-Sky" Background Files thread contains instructions on how to select a file and match it to a specific observation.

ACIS Grating Data

  • Time-dependent ACIS Gain (TGAIN) Files

    There are new time-dependent ACIS Gain (TGAIN) files for 01 May 2007 - 31 July 2007 (Epoch 30):

    acisD2007-02-01t_gainN0005.fits
    acisD2007-02-01t_gainN0006.fits
    acisD2007-05-01t_gainN0002.fits
    acisD2007-05-01t_gain_biN0002.fits
    

    The files are applicable to -120 C data only. The acisD2007-05-01t_gain[_bi]N0002.fits files are the new default proccesing files in the CALDB.

    These plots illustrate the degree of change the new files will produce in comparison with the old files.

    Epoch 30

    In both of the above figures it is apparent that the T_GAIN correction at the I3 aimpoint is diminishing over Epochs 28 - 30.

    In the S3 case, the general trends with energy and Epoch number are the same for the CTI and non-CTI cases by comparison, but with clear differences between them in specific values particularly above 5 keV. This is normal for recent epochs with T_GAIN corrections.

    Users working with ACIS data taken during this period may wish to reprocess to improve the TGAIN calibration in their data. The DATE-OBS header keyword records the observation start date.

    Note that unless you are fitting a spectra with oxygen emission lines, the gain refinement is unlikely to have an effect on the spectrum larger than the uncertainties in determining the gain.

  • ACIS Blank-Sky Background Files

    The newest versions of the ACIS blank-sky background files are now available in the CALDB.

    This set of ACIS background files includes:

    • files for -120 C data on ACIS-5 or ACIS-7 with CTI_APP = PPPPPBPBPP header keyword value (i.e. parallel and serial CTI applied to the back-illuminated chips)

    • CTI-corrected files for ACIS-8 (ACIS-S4).

    • upgrades to the files for chips 1-3, 5-7, and 8 with ACIS-S in the focal plane. These files include the newest CTI and TGAIN corrections.

      The non-CTI-corrected background files for these chips have the TGAIN applied. This matches how observational data at -120 C without the CTI-correction would be processed.

    The Using the ACIS "Blank-Sky" Background Files thread contains instructions on how to select a file and match it to a specific observation.

HRC-I Imaging and Grating Data

  • HRC-I Degap

    A new gap lookup table, hrciD1999-07-22gaplookupN0003.fits, is needed to improve the off-aimpoint gap map solution for HRC-I at certain locations.

    New observations of Capella from December 2005 - January 2006 and January 2007 were used to improve the degap solution for the CRSU=12-13 region, while including a slightly more optimized solution for other detector positions. The details of the refinements are presented in the memorandum HRC-I Degap Lookup from Capella Data - 2007 [http://hea-www.harvard.edu/%7Ejuda/memos/hrci_degap_lookup/capella/degap/2007/degap_lookup.html].

    Users must reprocess the data with hrc_process_events to apply the new calibration, e.g. by following the Create a New Level=2 Event File thread. The correct file will automatically be chosen by the tool.


How CIAO 4.0 Beta 2 Affect Your Analysis

The tool updates in CIAO 4.0 Beta 2 are limited to bug fixes. These changes will not adversely affect any analysis in progress.

Tools

acis_process_events

  • Bug fix: the stop time of afterglow badpixels was not being correctly used. The afterglow badpixels are now marked as bad (bit 16) until the stop time, not the end of the observation.

  • Bug fix: after a file is reprocessed, the values of PHA_RO are equal to the summed pulse height of the original, unadjusted event island (PHAS).

axbary

  • Bug fix: corrected a issue that appeared when the nput filename is > 49 characters and the output filename is < 49.

dmdiff

  • Bug fix: the tool would not detect differences between the vector arrays of the input files, e.g. comparing columns CHIP(CHIPX,CHIPY).

dmimgthresh

  • Bug fix: running the tool with cut=<value>: or cut=:<value> would treat the unspecified limit as "0".

dmmakereg

  • Bug fix: a bug existed when the shapes that are being printed don't all have the same number of points (e.g. one is a circle and one is a polygon).

dmstat

  • Images with dmBTYE datatype (8-bit unsigned integer) are now supported.

hrc_dtfstats

  • Bug fix: if the tool was run with the wrong input file, e.g. an evt2 instead of the dtf file, it would appear to run but created no output.

hrc_process_events

  • Bug fix: the tool would fail if given a level 2 file as input, rather than printing an error message.


Parameter Files

The CIAO 4.0 Beta software establishes a separate local parameter file directory, ~/cxcds_param_beta. This allows users to run both CIAO 3.4 and CIAO 4.0 Beta without having to worry about parameter file conflicts.

ciao.par

  • The filtwin_init and max_savestates parameters have been removed from ciao.par, since the filtwin application is no longer part of CIAO.


User Interface

Prism

  • The plotting capabilities of the prism file browsing GUI - i.e. the "Interactive Plot" or "Histogram" options in the "Visualization" menu - are once again available, assuming the ChIPS application is installed.


Documentation

ChIPS Website

  • There is a new website dedicated to the ChIPS plotting package: http://cxc.harvard.edu/chips.

Ahelp

  • The options to have ahelp open a web browser and display an HTML version of the help page have been removed. These options were "-i" (display HTML fom the CIAO website) and "-w" (display HTML packaged with CIAO).

Analysis Threads

  • The CIAO Science Threads are in the process of being updated for the CIAO 4.0 Beta 2 release. Please check the "Last Update" information at the top of each thread to see if it has been reviewed yet.

  • Threads and scripts that were removed at CIAO 4.0 Beta 1 due to dependencies on ChIPS will be made available shortly as well.



Last modified: 28 September 2015
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