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Last modified: 13 December 2017

URL: http://cxc.harvard.edu/caldb/prop_plan/pimms/pimms.html

Cycle 20 PIMMS Effective Area Public Information

Return to: PIMMS Index

Released as of 14 DEC 2017



The Chandra effective areas are built for sixteen configurations implemented in the PIMMS EA viewer and count rate calculator facility. Four of the configurations are for the default aim-point positions for each of the four detector arrays aboard Chandra, specifically the ACIS-I, ACIS-S, HRC-I and HRC-S routines. Cycle 20.

The other twelve configurations involve one or the other of the transmission gratings. For the HETG/ACIS-S configurations the default SIM_Z positions do not correspond to the above aim point settings, but instead are offset to minimize the ACIS CTI effect. A default SIM_Z offset of -3.0 mm (in the direction of the readouts) is used for HETG/ACIS-S.

As in previous years, model observations have been selected so that the zeroth order ARFs, as well as the first order GARFs will correspond to the appropriate positions on the ACIS-S array. The same is true for the LETG/HRC-S configuration, where the default zeroth order position does not necessarily coincide with the default imaging aim point.

PIMMS effective area (EA) files are built using model observations (OBSIDs) with standard/default detector and SIM_Z configurations with the CIAO 4.9 routines mkarf for imaging aimpoint cases and mkgarf for gratings configurations, using the most current CALDB input files (CALDB 4.7.7). The following table gives the input CALDB file information used by mkarf or mkgarf to generate the respective effective area files (as ARFs) for the Cycle 19 (N0019) and Cycle 20 (N0020) proposal cycles. Plots of the PIMMS effective areas may be viewed at the PIMMS Effective Area Data page. You may also use the automated Chandra Effective Area Viewer.

PIMMS Input Data and Procedure Changes for Cycle 20:

CalDB Input File Uprades (since Cycle 19):

  1. HRC-I QE version N0010 replaces N0009: This results in a nearly 20% reduction in the effective area below 672 eV, and 5% reduction for the rest of the spectrum for both HRC-I configurations.

  2. HRC-S QEU upgrade to version N0008, and the switch the 2019 QEU file: The QEU upgrade to version N0008 introduces width changes and shifts in energy of the plate edges in HRC-S. For the orders one or higher, this introduces some streaks in the difference plots near the nominal edge positions. The change from QEU N0007 of 2018 to N0008 of 2019 also results in a uniform -14% broadband change in the EA of all HRC-S-related configurations. See the difference plots for the HRC-S-related configurations on the PIMMS Index Page for CY20. (The other inputs to the HRC-S-related EA's have not changed.)

Parameter Input Changes (versus CY19 inputs):

  1. Imaging aimpoints:Due to the thermal cycling of the Chandra Aspect Camera, the aimpoint drift has become irregular, and an operational scheme has been adopted to fix targets dynamically at the desired location. This results in a permanent aimpoint location for each chip as a matter of course (which may be changed programatically if necessary, but not due to drift. See the Table below, and the Proposers Observatory Guide (POG) Table 6.4. The permanent aim point locations were set for the Cycle 18 release, and remain so for the current cycle.

  2. ACIS CONTAM time-delay parameter: The CIAO ARF- and GARF-generating routines employ a time-delay option in the "detsubsys" parameter specification, wherein a TT date value in seconds may be entered to set the date for the time-dependent CONTAM calculations. For Cycle 20 the value is 674265669.184, which corresponds to UTC date 15 May 2019. For Cycle 19 the value was 642729669.184, corresponding to 15 May 2018. This affects all and only ACIS configurations. For ACIS-S aimpoint position EAs and grating zeroth order EAs, the change is at most -6% at the Carbon Edge, and significantly less elsewhere.


TABLE 1

Configuration (CHIPX, CHIPY) ObsID Used HRMA QE QEU ACIS FI DEAD AREA ACIS CONTAM CONTAM TIME DELAY ACIS OSIP GREFF CALDB Filenames
ACIS-I (970.0, 975.0) 9768 hrmaD1996-12-20axeffaN0008.fits acisD1997-04-17qeN0006.fits acisD2010-02-01qeuN0007.fits acisD1999-09-16dead_areaN0001.fits acisD1999-08-13contamN0010.fits 642729669.184
674265669.184
N/A N/A acisiD2016-11-22pimmsN0019.fits
acisiD2017-11-29pimmsN0020.fits
ACIS-S (210.0, 520.0) 9300 hrmaD1996-12-20axeffaN0008.fits acisD1997-04-17qeN0006.fits acisD2010-02-01qeuN0007.fits acisD1999-09-16dead_areaN0001.fits acisD1999-08-13contamN0010.fits 642729669.184
674265669.184
N/A N/A acissD2016-11-22pimmsN0019.fits
acissD2017-11-29pimmsN0020.fits
HRC-I (7590.0, 7745.0) 8531 hrmaD1996-12-20axeffaN0008.fits hrciD1999-07-22qeN0009.fits
hrciD1999-07-22qeN0010.fits
hrciD1999-07-22qeuN0002.fits N/A N/A N/A N/A N/A hrciD2016-11-22pimmsN0019.fits
hrciD2017-11-29pimmsN0020.fits
HRC-S (2095.0, 8915.0) 9630 hrmaD1996-12-20axeffaN0008.fits hrcsD2012-03-29qeN0014.fits hrcsD2018-01-01qeuN0007.fits
hrcsD2019-01-01qeuN0008.fits
N/A N/A N/A N/A N/A hrcsD2016-11-22pimmsN0019.fits
hrcsD2017-11-29pimmsN0020.fits
HETG0/ACIS-I (970.0, 975.0) 9768 hrmaD1996-12-20axeffaN0008.fits acisD1997-04-17qeN0006.fits acisD2010-02-01qeuN0007.fits acisD1999-09-16dead_areaN0001.fits acisD1999-08-13contamN0010.fits 642729669.184
674265669.184
N/A hetgD1996-11-01greffpr001N0007.fits acisihetg0D2016-11-22pimmsN0019.fits
acisihetg0D2017-11-29pimmsN0020.fits
HETG0/ACIS-S (211.2, 369.3) 7280 hrmaD1996-12-20axeffaN0008.fits acisD1997-04-17qeN0006.fits acisD2010-02-01qeuN0007.fits acisD1999-09-16dead_areaN0001.fits acisD1999-08-13contamN0010.fits 642729669.184
674265669.184
N/A hetgD1996-11-01greffpr001N0007.fits acisshetg0D2016-11-22pimmsN0019.fits
acisshetg0D2017-11-29pimmsN0020.fits
HEG1/ACIS-S (211.2, 369.3) 7280 hrmaD1996-12-20axeffaN0008.fits acisD1997-04-17qeN0006.fits acisD2010-02-01qeuN0007.fits acisD1999-09-16dead_areaN0001.fits acisD1999-08-13contamN0010.fits 642729669.184
674265669.184
acisD2000-01-29osip_ctiN0006.fits hetgD1996-11-01greffpr001N0007.fits acissheg1D2016-11-22pimmsN0019.fits
acissheg1D2017-11-29pimmsN0020.fits
HEGMEG1/ACIS-S (211.2, 369.3) 7280 hrmaD1996-12-20axeffaN0008.fits acisD1997-04-17qeN0006.fits acisD2010-02-01qeuN0007.fits acisD1999-09-16dead_areaN0001.fits acisD1999-08-13contamN0010.fits 642729669.184
674265669.184
acisD2000-01-29osip_ctiN0006.fits hetgD1996-11-01greffpr001N0007.fits acisshegmeg1D2016-11-22pimmsN0019.fits
acisshegmeg1D2017-11-29pimmsN0020.fits
MEG1/ACIS-S (211.2, 369.3) 7280 hrmaD1996-12-20axeffaN0008.fits acisD1997-04-17qeN0006.fits acisD2010-02-01qeuN0007.fits acisD1999-09-16dead_areaN0001.fits acisD1999-08-13contamN0010.fits 642729669.184
674265669.184
acisD2000-01-29osip_ctiN0006.fits hetgD1996-11-01greffpr001N0007.fits acissmeg1D2016-11-22pimmsN0019.fits
acissmeg1D2017-11-29pimmsN0020.fits
LETG0/ACIS-I (970.0, 975.0) 9768 hrmaD1996-12-20axeffaN0008.fits acisD1997-04-17qeN0006.fits acisD2010-02-01qeuN0007.fits acisD1999-09-16dead_areaN0001.fits acisD1999-08-13contamN0010.fits 642729669.184
674265669.184
acisD2000-01-29osip_ctiN0006.fits letgD1996-11-01greffpr001N0007.fits acisiletg0D2016-11-22pimmsN0019.fits
acisiletg0D2017-11-29pimmsN0020.fits
LETG0/ACIS-S (210.0 520.0) 10662 hrmaD1996-12-20axeffaN0008.fits acisD1997-04-17qeN0006.fits acisD2010-02-01qeuN0007.fits acisD1999-09-16dead_areaN0001.fits acisD1999-08-13contamN0010.fits 642729669.184
674265669.184
acisD2000-01-29osip_ctiN0006.fits letgD1996-11-01greffpr001N0007.fits acissletg0D2016-11-23pimmsN0019.fits
acissletg0D2017-11-29pimmsN0020.fits
LEG1/ACIS-S (210.0 520.0) 10662 hrmaD1996-12-20axeffaN0008.fits acisD1997-04-17qeN0006.fits acisD2010-02-01qeuN0007.fits acisD1999-09-16dead_areaN0001.fits acisD1999-08-13contamN0010.fits 642729669.184
674265669.184
acisD2000-01-29osip_ctiN0006.fits letgD1996-11-01greffpr001N0007.fits acissleg1D2016-11-23pimmsN0019.fits
acissleg1D2017-11-29pimmsN0020.fits
LETG0/HRC-I (7590.0, 7745.0) 8531 hrmaD1996-12-20axeffaN0008.fits hrciD1999-07-22qeN0009.fits
hrciD1999-07-22qeN0010.fits
hrciD1999-07-22qeuN0002.fits N/A N/A N/A N/A letgD1996-11-01greffpr001N0007.fits hrciletg0D2016-11-22pimmsN0019.fits
hrciletg0D2017-11-29pimmsN0020.fits
LETG0/HRC-S (2116.9, 8850.3) 331 hrmaD1996-12-20axeffaN0008.fits hrcsD2012-03-29qeN0014.fits hrcsD2018-01-01qeuN0007.fits
hrcsD2019-01-01qeuN0008.fits
N/A N/A N/A N/A letgD1996-11-01greffpr001N0007.fits hrcsletg0D2016-11-22pimmsN0019.fits
hrcsletg0D2017-11-29pimmsN0020.fits
LEG1/HRC-S (2116.9, 8850.3) 331 hrmaD1996-12-20axeffaN0008.fits hrcsD2012-03-29qeN0014.fits hrcsD2018-01-01qeuN0007.fits
hrcsD2019-01-01qeuN0008.fits
N/A N/A N/A N/A letgD1996-11-01greffpr001N0007.fits hrcsleg1D2016-11-22pimmsN0019.fits
hrcsleg1D2017-11-29pimmsN0020.fits
LEGHI/HRC-S (2116.9, 8850.3) 331 hrmaD1996-12-20axeffaN0008.fits hrcsD2012-03-29qeN0014.fits hrcsD2018-01-01qeuN0007.fits
hrcsD2019-01-01qeuN0008.fits
N/A N/A N/A N/A letgD1996-11-01greffpr001N0007.fits hrcsleghiD2016-11-22pimmsN0019.fits
hrcsleghiD2017-11-29pimmsN0020.fits

Notes for Table 1:

None.

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Last modified: 13 December 2017
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