HRC-I Calibration Data Products - Pre-flight/In-Flight
Previous update - 13 December 2000
Update - 20 September 2002
(Added text to Out-of-Band Response section)
Update - 12 November 2002
(Added Chandra Calibration Workshop 2002 Visible/UV Response presentation
and memo on summary of Vega count rate results)Table of Contents
Pre-Flight
Focal Plane Layout
Flat Field Maps
HRC-I QE and Effective Area
QE Fine Structure (postscript file)
HRC-I Out-of-Band Response
Spatial Scale
Active Area
Count Rate Linearity
Point Spread Function
Pulse Height Distributions as a Function of Energy
Quantum Efficiency vs Angle of IncidenceIn-Flight
Degap Corrections
Encircled Energy
Encircled Energy vs Angle Off-axis
Background
Effective Area
Return to previous pageFlat Field Maps (64 x 64; in absolute QE)
In order to download the fits files below, hold down the "Shift" key and click on "fits file".
How to display postscript plots with the Netscape browser.
Postscript images show a surface plot, frequency histogram, and u and v projections.
E(eV) 183 fits file postscript file 277 fits file postscript file 525 fits file postscript file 851 fits file postscript file 1487 fits file postscript file 4511 fits file postscript file 6404 fits file postscript file
Model QE of HRC-I MCPs. Data from the XRCF, flat field, and synchrotron calibrations and tests were incorporated in this model . No values below 277 eV are given due to experimental inconsistencies in the data.
Quantum Efficiency Calibration of HRC-I (postscript file)
Data table containing the HRC-I QE:
HRC-I/HRMA effective area model. Model: hrci_uv.ps (postscript file)
Transmission of UV/Ion shield: hrci_uvt.prn
HRC-I Quantum Efficiency (MCP QE x UVIS Trans.): hrci_uvqe.prn
Transmission and QE files (prn) consist of two columns; first column: wavelength in Angstroms, second column; transmission or qe, respectively.
HRC-I/HRMA effective area model for out-of-band ultraviolet and visible light. (1100 cm^2 x HRC-I QE) U, V axis: 6.429 microns per pixel
u dimension: 92.56 mmv dimension: 92.77 mm
Uncertainty is +/-0.05 mm.
In focus count rate linearity of the HRC-I at 277 eV. See also Count Rate Linearity of the AXAF High Resolution Camera (HRC), D. Pease and H. Donnelly (postscript file) or HTML file).
A model of electronic deadtime and telemetry saturation (extended source count rate linearity).
See HRC Deadtime and Telemetry Saturation, M. Juda and A. Dobrzycki (postscript file) for a complete discussion.
Surface plot of the point spread function of the combined HRC-I and HRMA at Carbon K alpha (277 eV). No FAM motion.
Projection of the PSF above onto the u-axis. The FWHM is 38 um.
Projection of the PSF above onto the v-axis. The FWHM is 32 um.
Encircled energy versus radius of the HRC-I/HRMA at 277 eV.
Pulse Height Distributions as a Function of Energy
HRC-I pulse height distributions versus energy and the centroids of pulse height versus energy.
Quantum Efficiency vs Angle of Incidence
The relative quantum efficiency of a set of MCPs similar to the FM HRC-I MCPs was measured as a function of incident angle for the energy 1.49 keV at two azimuth angles. We have recently extended these measurements in our laboratory to more energies and azimuth angles. A report can be found at http://hea-www.harvard.edu/HRC/calib/pore_ang.ps (postscript file)
The relative QE vs incident angle (E = 1.49 keV, azimuth = 0 degrees)
The relative QE vs incident angle (E = 1.49 keV, azimuth = -180 degrees)
The following diagram defines the angles theta (incident angle) and phi (azimuth angle) for the measurements:
In-Flight
Degap Corrections (31 October 1999)
- U correction for positive fine positions:
hrci_cal_2_good_flatpu_deg.cor- U correction for negative fine positions:
hrci_cal_2_good_flatmu_deg.cor- V correction for positive fine positions:
hrci_cal_2_good_flatpv_deg.cor- V correction for negative fine positions:
hrci_cal_2_good_flatmv_deg.corFor an explanation of the tables above:
Degap Corrections for HRC-I and HRC-S Detectors (A postscript memorandum)
Degap as a Transformation of Probability Distribution Problem (A postscript memorandum)
For the combined HRC-I/HRMA, the predicted and observed (AR Lac) fractional encircled energy as a function of radius for an on-axis point source. The predictions for 0.277 keV and 6.40 keV X-rays include contributions of the finite resolution of HRC-S and the aspect solution to the encircled energy.
Encircled Energy vs Angle Off-axis
Encircled energy as a function of source off-axis angle for 50% and 90% encircled energy for 1.49 keV and 6.40 keV X-rays for the combined HRC-I/HRMA.
HRC-I background map during quiescent periods (anti-coincidence shield veto enabled and ground filtering of events). Average background is 9 x 10 -6 ct s-1 arcsec-2 with an approx. 10% gradient from bottom to top. The detector is oriented as in the Focal Plane Layout figure above (u=0, v=0, at the top corner). Smoothing was done via wavelet decomposition. Contours are 8.3 - 9.7 x 10 -6 ct s-1 arcsec-2. The background can increase from a factor 2 to 10 times the quiescent value due to charged particles. About 20% of the observing time is affected by these events.
The effective area of the HRMA/HRC-I (dashed line) and the "T" region of the central segment of the HRMA/HRC-S (solid line) integrated over the full PSF. Absorption edges are due to the iridium coating of the telescope, the CsI MCP coating, and the polyimide/Al of the UVIS. The results of the low energy in-flight QE calibration have been incorporated into these curves. Effective area table (First column is energy in eV, fifth column is effective area in cm2)
ReferencesPerformance and Calibration of the AXAF High Resolution Camera: I. Imaging Readout (Kenter, A.T., et al., 1997; in postscript) gives details of the measurement procedures, analysis techniques, and results of the XRCF and flat field calibrations.
In-flight Performance of the Chandra High Resolution Camera (Murray, S.S., et al., 2000; in postscript)
In-flight Performance and Calibration of the Chandra High Resolution Camera Imager (Kenter, A.T., et al., 2000; in postscript)
The Out-of-band Response of the HRC on Chandra (Zombeck, M.V., et al., 2000, in postscript)
Event Screening for the Chandra X-ray Observatory High Resoloution Camera (HRC) (Murray, S.S., et al., 2000; in postscript)
Improving Chandra High Resolution Camera event positions via corrections to cross-grid charge detector signals (Juda, M., et al., 2000; in postscript)
Time Tag Investigation (pdf file)
The UV/Visible Light Sensitivity of the HRC, Chandra Calibration Workshop, 2002.
Response of the HRC to Vega, memo, October 28, 2002.
How to display postscript plots with the Netscape browser.
