ACIS
ACIS DOSE Registered-Photon-Map
The steps we took to compute the dose map are;
- Level 1 Event files for a specified month are obtained from archive.
- Image data including I2, I3, S2, S3 CCDs are extracted from all event files.
- All the extracted image data were merged to create a month long exposure map for the month.
- The exposure map is opened with ds9, and check a distribution of count rates against energy. From this, estimate the upper threshold value. Any events beyond this upper threshold are assumed erroneous events such as bad pixels.
- Using this upper threshold, the data is filtered, and create a cleaned exposure map for the month.
- The exposure map from each month from the Sep 1999 is added up to create a cumulative exposure map for each month.
- Using fimgstatistic, we compute count rate statistics for each CCDs.
- For observations with high data drop rates (e.g., Crab nebula, Cas A), we corrected the observations by adding events.
Please check more detail plots at Telemetered Photon Dose Trend page.
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Statistics: # IMAGE NPIX MEAN RMS MIN MAX ACIS_may26 6004901 3.530 4.061 0.0 384 I2 node 0 262654 3.232877 2.050189 0.0 76.0 I2 node 1 262654 3.405158 2.136471 0.0 77.0 I2 node 2 262654 3.317874 2.062444 0.0 98.0 I2 node 3 262654 3.321475 2.146532 0.0 225.0 I3 node 0 262654 3.978031 2.301347 0.0 86.0 I3 node 1 262654 3.908272 2.254287 0.0 96.0 I3 node 2 262654 3.745216 2.169739 0.0 53.0 I3 node 3 262654 3.719002 2.193002 0.0 97.0 S2 node 0 262654 4.606637 2.398170 0.0 69.0 S2 node 1 262654 4.704984 2.745881 0.0 230.0 S2 node 2 262654 4.734417 2.624330 0.0 285.0 S2 node 3 262654 4.593106 2.558230 0.0 384.0 S3 node 0 262654 6.502390 2.791410 0.0 58.0 S3 node 1 262654 7.630268 3.141364 0.0 55.0 S3 node 2 262654 7.260662 2.844607 0.0 36.0 S3 node 3 262654 6.361936 2.639499 0.0 44.0
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Statistics: IMAGE NPIX MEAN RMS MIN MAX ACIS_total 6004901 2786.856 3504.078 0.0 169725 I2 node 0 262654 2418.767074 493.054765 515.0 16372.0 I2 node 1 262654 2560.312607 723.944947 530.0 167719.0 I2 node 2 262654 2589.314166 557.168033 551.0 18288.0 I2 node 3 262654 2600.554503 686.317163 509.0 38025.0 I3 node 0 262654 2829.739944 732.267217 508.0 18320.0 I3 node 1 262654 2885.814954 1765.657592 538.0 56136.0 I3 node 2 262654 2582.247705 488.371010 504.0 15839.0 I3 node 3 262654 2552.540553 523.042698 487.0 38734.0 S2 node 0 262654 3245.383498 525.819006 1745.0 22724.0 S2 node 1 262654 3449.427568 791.287693 1919.0 23416.0 S2 node 2 262654 3828.245378 797.643458 2335.0 34661.0 S2 node 3 262654 3783.708253 659.736139 2050.0 90902.0 S3 node 0 262654 5766.490215 3174.403355 2525.0 56898.0 S3 node 1 262654 6964.714955 2420.521724 0.0 83602.0 S3 node 2 262654 5701.404358 1401.612686 2689.0 27896.0 S3 node 3 262654 4489.025354 800.448477 2695.0 26993.0
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The Mean Detrended CTI
We report CTIs with a refined data definition. CTIs were computed for the temperature dependency corrected data. Please see CTI page for detailed explanation. CTI's are computed for Mn K alpha, and defined as slope/intercept x10^4 of row # vs ADU. Data file: here
Imaging CCDs
Spectral CCDs
Backside CCDs
Focal Plane Temperature
May 2026 Focal Temperature
| The Mean (max) FPT: | |
|---|---|
| -107.53 | +/- 7.69 C |
| Mean Width: | |
| 0.8 | +/- 0.58 days |
Averaged Focal Plane Temperature
We are using 10 period moving averages to show trends of peak temperatures and peak widths. Note, the gaps in the width plot are due to missing/corrupted data.
Focal Plane Temperature, Sun Angle and Altitude
Bad Pixels
The plots below were generated with a new warm pixel finding script. Please see Acis Bad Pixel Page for details.
Front Side CCDs
Back Side CCD (CCD5)
Science Instrument Background Rates
| Name | Low (keV) | High(KeV) | Description |
|---|---|---|---|
| SSoft | 0.00 | 0.50 | Super soft photons |
| Soft | 0.50 | 1.00 | Soft photons |
| Med | 1.00 | 3.00 | Moderate energy photons |
| Hard | 3.00 | 5.00 | Hard Photons |
| Harder | 5.00 | 10.00 | Very Hard photons |
| Hardest | 10.00 | Beyond 10 keV |
The following three plots show trends of SIB from year 2000. CCDs shown here are CCD3, CCD5, and CCD7. Fitted lines are linear fit after eliminating extreme outliers. For >10 keV plots, 2 lines are fit. One is with a 13 keV filter, and another without.
CCD 3
CCD 5
CCD 7
ACIS Histogram Mode Trends
We collected data from acis histogram mode data, and created trend plots of peak portions and peak widths against time (DOM). The peaks were estimated by fitting a simple Gaussian on three peaks (Al, Ti, and Mn), and the widths were estimated by a width at the half max from the peak.
All histogram data are taken under TIMED and GRADED_HIST mode, SIM position is at an external calibration source position, the focal temperature is around -119.7 C, and parameter settings in aciselec, acistemp are set to about same for all.
CCD 3, Peak Position
CCD 3, Peak Widths
CCD 3, Count Rates
HRC
DOSE of Central 4K Pore-Pairs
Please refer to Maximum Dose Trends for more details.
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IMAGE NPIX MEAN STDDEV MIN MAX HRCI_05_2026.fits 16777216 0.011 0.105 0.000 3.000
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IMAGE NPIX MEAN STDDEV MIN MAX HRCI_08_1999_05_2026.fits 16777216 na na na na
No Data
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IMAGE NPIX MEAN STDDEV MIN MAX HRCS_08_1999_05_2026.fits 16777216 na na na na
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Max dose trend plots corrected for events that "pile-up"
in the center of the taps due to bad position information.
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Gratings
Grating Trends/Focus
We plot the width of the zero order streak of ACIS/HETG observations and the width of the zero order image for HRC/LETG observations of point sources. No significant defocusing trend is seen at this time. See Gratings Trends pages.
PCAD
ACA Trending
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Gyro Bias Drift
Radiation History
Radiation Count Rates of May 2026
Sun Spot History (See:NOAA Page)
Trending
Quarterly Trends
- HRMA Heater
| Previous Quarter | |||||||
| MSID | MEAN | RMS | DELTA/YR | DELTA/YR/YR | UNITS | DESCRIPTION | |
| ohrthr03 | -0.001 | 8.917e-05 | (2.96+/-0.00)e2 | 0.09 +/- 0.02 | K | RT 5: HRMA FORWARD APERTURE PLATE | |
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| ohrthr09 | -0.002 | 2.213e-04 | (2.97+/-0.01)e2 | 0.19 +/- 0.06 | K | RT 105: HRMA CAP | |
| ohrthr17 | -0.002 | 2.264e-04 | (2.97+/-0.01)e2 | 0.19 +/- 0.07 | K | RT 125: HSA OUTER CYNLINDER | |
| ohrthr24 | -0.003 | 3.985e-04 | (2.98+/-0.01)e2 | 0.46 +/- 0.18 | K | RT 12: HRMA AFT HEATER PLATE | |
| ohrthr38 | -0.002 | 9.930e-04 | (3.03+/-0.02)e2 | 0.67 +/- 0.66 | K | RT 120: HRMA AFT COLLIMATOR OUTER CYLINDER | |
| ohrthr52 | -0.002 | 2.273e-04 | (2.96+/-0.01)e2 | 0.20 +/- 0.07 | K | RT 100: HRMA CAP | |
- HRMA Thermal
| Previous Quarter | |||||||
| MSID | MEAN | RMS | DELTA/YR | DELTA/YR/YR | UNITS | DESCRIPTION | |
| 4rt568t | -0.002 | 0.001 | (3.02+/-0.02)e2 | 0.84 +/- 0.69 | K | RT 568 - HRMA TEMP | |
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| 4rt569t | -0.002 | 3.541e-04 | (2.98+/-0.01)e2 | 0.38 +/- 0.15 | K | RT 569 - HRMA TEMP | |
| 4rt570t | -0.002 | 2.123e-04 | (2.97+/-0.01)e2 | 0.16 +/- 0.06 | K | RT 570 - HRMA TEMP | |
| 4rt575t | -0.001 | 0.001 | (3.08+/-0.03)e2 | 0.79 +/- 0.91 | K | RT 575 - OB CONE TEMP | |
| 4rt576t | -0.002 | 0.001 | (2.98+/-0.03)e2 | 0.73 +/- 0.71 | K | RT 576 - OB CONE TEMP | |
| 4rt578t | -0.002 | 0.002 | (3.07+/-0.04)e2 | 1.39 +/- 1.10 | K | RT 578 - OB CONE TEMP | |
- MUPS
| Previous Quarter | |||||||
| MSID | MEAN | RMS | DELTA/YR | DELTA/YR/YR | UNITS | DESCRIPTION | |
| pm1thv1t | -0.002 | 0.008 | (3.61+/-0.18)e2 | -0.56 +/- 3.45 | K | MUPS 1 THRUSTER VALVE 01 TEMP | |
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| pline02t | -6.632e-05 | 0.006 | (3.49+/-0.14)e2 | 0.92 +/- 3.39 | K | PROP LINE TEMP 02 | |
| pline03t | -5.320e-04 | 0.006 | (3.39+/-0.14)e2 | 0.72 +/- 2.42 | K | PROP LINE TEMP 03 | |
| pline04t | -0.008 | 0.005 | (3.30+/-0.11)e2 | 2.71 +/- 2.91 | K | PROP LINE TEMP 04 | |
Spacecraft Motions
TSC and FA Cummulative Moter Distance
HETG and LETG Cummulative Insertion Counts
HETG/LETG Insertion/Retraction Angle
Reaction Wheel Rotations
