Optics | Wolter Type-I |
Mirror coatings | Iridium |
Mirror outer diameters (1, 3, 4, 6) | 1.23, 0.99, 0.87, 0.65 m |
Mirror lengths | 84 cm |
Unobscured clear aperture | 1145 cm2 |
Focal length | 10.066 m |
Plate scale | 48.8 µm/arcsec |
PSF FWHM (with detector) | 0.5 arcsec |
Ghost-free field of view | 30 arcmin diameter |
Effective Area: | |
@ 0.25 keV | 800 cm2 |
@ 5.0 keV | 400 cm2 |
@ 8.0 keV | 100 cm2 |
Read more in the HRMA chapter of the Proposer's Observatory Guide |
Focal plane arrays: | |
I-array (ACIS-I) | 4 CCDs placed to lie tangent to the focal surface, used for imaging |
S-array (ACIS-S) | 6 CCDs in a linear
array tangent to the grating Rowland circle, used for either imaging or as a grating readout |
CCD format | 1024 by 1024 pixels |
Pixel size | 24.0 µm (0.492 ± 0.0001 arcsec) |
ACIS-I array size | 16.9 by 16.9 arcmin |
ACIS-S array size | 8.3 by 50.6 arcmin |
On-axis effective area of frontside illuminated (FI) chips (integrated over the PSF to >99% encircled energy): | |
@ 0.5 keV | 110 cm2 |
@ 1.5 keV | 600 cm2 |
@ 8.0 keV | 40 cm2 |
Quantum efficiency for FI chips: | |
3.0 - 5.0 keV | > 80% |
0.8 - 8.0 keV | > 30% |
Quantum efficiency for backside illuminated (BI) chips: | |
0.8 - 6.5 keV | > 80% |
0.3 - 8.0 keV | > 30% |
Maximum readout rate per channel | ~ 100 kpix/sec |
Minimum row readout time | 2.8 ms |
Nominal frame time | 3.2 sec (full frame) |
Allowable frame times | 0.2 to 10.0 sec |
Frame transfer time | 41 µs (per row) |
Point-source sensitivity | 4 X 10-15 ergs/cm2/s in 104 s (0.4 to 6.0 keV) |
Read more in the ACIS chapter of the Proposer's Observatory Guide |
Focal plane arrays: | |
HRC-I: | CsI-coated microchannel plate pairs, 90 X 90 mm |
HRC-S: | CsI-coated microchannel plate pairs, 3-100 X 20 mm |
Field of view: | |
HRC-I | ~ 30 X 30 arcmin |
HRC-S | 6 X 90 arcmin |
Spatial resolution, FWHM: | ~ 20 µm, ~ 0.4 arcsec |
Energy range: | 0.08 - 10.0 keV |
Spectral resolution (E/dE): | ~ 1 @ 1 keV |
Quantum efficiency: | |
@ 1.0 keV | 30% |
@ 8.0 keV | 30% |
On-axis effective area: | |
HRC-I @ 0.277 keV | 133 cm2 |
HRC-I @ 1 keV | 227 cm2 |
Time resolution | 16 µs |
Limiting sensitivity   (point source, 3 sigma detection in 3 X 105 s) | 9 X 10-16erg/cm2/s |
On-orbit quiescent background (before ground processing): | |
HRC-I | 9 X 10-6cts/s/arcsec2 |
HRC-S | 1.8 X 10-4cts/s/(res. elm.) |
Read more in the HRC chapter of the Proposer's Observatory Guide |
HETGS range: | 0.4 - 10.0 keV (31 - 1.2 Å) |
High Energy Grating (HEG) range: | 0.8 - 10.0 keV (15 - 1.2 Å) |
Medium Energy Grating (MEG) range: | 0.4 - 5.0 keV (31 - 2.5 Å) |
Effective area (MEG+HEG first orders, with ACIS-S): | |
@ 0.5 keV | 7 cm2 |
@ 1.0 keV | 59 cm2 |
@ 1.5 keV | 200 cm2 |
@ 6.5 keV | 28 cm2 |
Resolving power (E/dE): | |
HEG: | 65 - 1070 (1000 @ 1 keV, 12.4 Å) |
MEG: | 80 - 970 (660 @ 0.826 keV, 15 Å) |
Resolution: | |
d lambda, HEG: | 0.012 Å FWHM |
d lambda, MEG: | 0.023 Å FWHM |
Absolute wavelength accuracy: | |
HEG: | ± 0.006 Å |
MEG: | ± 0.011 Å |
Wavelength scale: | |
HEG: | 0.0055595 Å / ACIS pixel |
MEG: | 0.0111185 Å / ACIS pixel |
Read more in the HETG chapter of the Proposer's Observatory Guide |
Wavelength range: | |
HRC-S | 1.7 - 170 Å |
ACIS-S | 1.4 - 63 Å |
Energy range: | |
HRC-S | 0.07 - 7.29 keV |
ACIS-S | 0.20 - 8.86 keV |
Resolution: (d lambda, FWHM) | 0.05 Å |
Resolving power: (E/dE) | |
50 - 160 Å | >= 1000 |
3 - 50 Å | ~ 20 ⨉ λ |
Dispersion | 1.148 Å/mm |
Plate scale | 48.80 µm/arcsec |
Effective area (with HRC-S): | |
125 - 170 Å | 1 - 2 cm2 |
60 - 120 Å | 3 - 7 cm2 |
44 - 60 Å | 7 - 12 cm2 |
19 - 40 Å | 4 - 8 cm2 |
6 - 18 Å | 10 - 25 cm2 |
2 - 5 Å | 3 - 5 cm2 |
Background (quiescent) | |
HRC-S, on-orbit | 0.12 counts/pixel/100-ksec |
HRC-S, after filtering | ~ 0.04 counts/pixel/100-ksec |
ACIS-S, on-orbit | « 0.01 counts/pixel/100-ksec |
Read more in the LETG chapter of the Proposer's Observatory Guide |
Last modified: 01/08/21