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_mar26 6004901 5.614 15.717 0.0 2154 I2 node 0 262654 6.006616 3.164629 0.0 61.0 I2 node 1 262654 9.514933 6.189633 0.0 647.0 I2 node 2 262654 9.131047 4.599046 0.0 83.0 I2 node 3 262654 10.479576 5.351817 0.0 386.0 I3 node 0 262654 10.368628 5.826616 0.0 218.0 I3 node 1 262654 9.905619 5.011377 0.0 1143.0 I3 node 2 262654 7.719027 3.879046 0.0 75.0 I3 node 3 262654 5.715516 3.313325 0.0 715.0 S2 node 0 262654 4.659046 5.757867 0.0 647.0 S2 node 1 262654 5.344079 7.292914 0.0 740.0 S2 node 2 262654 6.400571 10.477926 0.0 632.0 S2 node 3 262654 5.660253 8.125090 0.0 637.0 S3 node 0 262654 11.727466 66.556658 0.0 2154.0 S3 node 1 262654 5.693277 6.013989 0.0 168.0 S3 node 2 262654 6.691613 9.977852 0.0 204.0 S3 node 3 262654 6.276179 10.166946 0.0 235.0
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Statistics: IMAGE NPIX MEAN RMS MIN MAX ACIS_total 6004901 2778.660 3496.550 0.0 169725 I2 node 0 262654 2411.109276 491.032648 514.0 16271.0 I2 node 1 262654 2548.954536 719.937691 529.0 167719.0 I2 node 2 262654 2579.768377 553.507916 551.0 18104.0 I2 node 3 262654 2593.200983 684.103142 509.0 37853.0 I3 node 0 262654 2821.201705 730.064644 508.0 17789.0 I3 node 1 262654 2876.907118 1764.548775 537.0 56122.0 I3 node 2 262654 2573.629081 485.992733 504.0 15766.0 I3 node 3 262654 2544.468719 520.705973 486.0 37864.0 S2 node 0 262654 3235.690782 523.932603 1740.0 22707.0 S2 node 1 262654 3438.781754 788.195133 1916.0 22911.0 S2 node 2 262654 3817.027103 794.942242 2330.0 34501.0 S2 node 3 262654 3772.533412 657.083220 2048.0 90122.0 S3 node 0 262654 5748.725176 3164.256502 2520.0 56843.0 S3 node 1 262654 6948.184275 2418.265770 0.0 83602.0 S3 node 2 262654 5685.874433 1399.667684 2678.0 27862.0 S3 node 3 262654 4475.569833 798.774094 2685.0 26967.0
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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
Mar 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 |
ACIS Rejected Events
The links below are plots of stat1 quantities, showing on-board rejected events. The average EVTSENT, DROP_AMP, DROP_POS, DROP_GRD, THR_PIX, and maximum BERR_SUM obtained from L1 acis*stat1.fits files are plotted for each observation. CTI observations are plotted separately from regular science observations.
Column definitions:
- EVTSENT - number of events sent in data record
- DROP_AMP - number of discarded events due to corrected amplitude
- DROP_POS - number of discarded events due to CCD position
- DROP_GRD - number of discarded events due to grade code
- THR_PIX - number of pixels above respective threshold level
- BERR_SUM - number of pixel bias errors so far in science run
Note the half-life decline of the CTI source is clearly evidenced in the steady janline of EVTSENT.
CCD3 Observations
| CTI | Science |
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CCD7 Observations
| CTI | Science |
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ACIS Gain Trends
We computed ACIS gain and offset from ACIS event1 files used in CTI computation, following the step described by C. Grant ACIS gain @ -120C page.
Instead computing gains and offsets from individual observations, we combined all data from each month and computed an monthly averaged gain and offset.
The following plots show CCD3 and CCD5 gains and offset trends.
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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_03_2026.fits 16777216 0.006 0.080 0.000 6.000
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IMAGE NPIX MEAN STDDEV MIN MAX HRCI_08_1999_03_2026.fits 16777216 na na na na
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IMAGE NPIX MEAN STDDEV MIN MAX HRCS_03_2026.fits 16777216 0.000 0.003 0.000 2.000
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IMAGE NPIX MEAN STDDEV MIN MAX HRCS_08_1999_03_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 Mar 2026
Sun Spot History (See:NOAA Page)
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Trending
Critical Trends
| ACIS Temperatures - Daily Maximums | |||||||
|---|---|---|---|---|---|---|---|
| MSID | MEAN | RMS | DELTA/YR | DELTA/YR/YR | UNITS | DESCRIPTION | |
| 1pdeaat | 0.009 | 0.002 | (3.06+/-0.05)e2 | -2.80 +/- 1.31 | K | PSMC DEA PS A TEMP | |
| HRMA Computed Averages - Daily Maximums | |||||||
|---|---|---|---|---|---|---|---|
| MSID | MEAN | RMS | DELTA/YR | DELTA/YR/YR | UNITS | DESCRIPTION | |
| obaavg | -0.018 | 0.001 | (3.02+/-0.03)e2 | -0.60 +/- 0.82 | TEMP | OBA/TFTE | |
| EPHIN Temperatures - Daily Maximums | |||||||
|---|---|---|---|---|---|---|---|
| MSID | MEAN | RMS | DELTA/YR | DELTA/YR/YR | UNITS | DESCRIPTION | |
| teio | -0.013 | 0.009 | (3.36+/-0.21)e2 | 5.15 +/- 3.60 | K | EPHIN ELECTRONICS HOUSING TEMP | |
| tephin | -0.029 | 0.004 | (3.42+/-0.08)e2 | 1.43 +/- 2.72 | K | EPHIN SENSOR HOUSING TEMP | |
| S/C Main Temperatures - Daily Maximums | |||||||
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| MSID | MEAN | RMS | DELTA/YR | DELTA/YR/YR | UNITS | DESCRIPTION | |
| tcylfmzm | 0.010 | 0.004 | (3.26+/-0.10)e2 | -2.11 +/- 2.11 | K | CNT CYL TEMP:-Z SIDE UNDER LAE-1 | |
| tcylfmzp | 0.010 | 0.004 | (3.29+/-0.09)e2 | -0.23 +/- 1.93 | K | CNT CYL TEMP:-Z SIDE UNDER LAE-2 | |
| S/C Ancillary Temperatures - Daily Maximums | |||||||
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| MSID | MEAN | RMS | DELTA/YR | DELTA/YR/YR | UNITS | DESCRIPTION | |
| tfssbkt1 | -0.029 | 0.013 | (3.60+/-0.30)e2 | 5.11 +/- 4.60 | K | FSS BRAC | |
| tfssbkt2 | -0.019 | 0.014 | (3.56+/-0.33)e2 | 5.24 +/- 4.61 | K | FSS BRAC | |
| tsctsf1 | -0.026 | 0.003 | (3.32+/-0.06)e2 | 2.05 +/- 2.05 | K | SC-TS FITTING -1 TEMP | |
| tsctsf6 | -0.030 | 0.003 | (3.31+/-0.06)e2 | 1.06 +/- 2.14 | K | SC-TS FITTING -6 TEMP | |
| MUPS - Daily Maximums | |||||||
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| MSID | MEAN | RMS | DELTA/YR | DELTA/YR/YR | UNITS | DESCRIPTION | |
| pm1thv1t | -0.026 | 0.008 | (3.61+/-0.18)e2 | 2.80 +/- 3.46 | K | MUPS 1 THRUSTER VALVE 01 TEMP | |
| pm2thv1t | -0.024 | 0.010 | (3.51+/-0.24)e2 | 3.47 +/- 4.22 | K | MUPS 2 THRUSTER VALVE 01 TEMP | |
| pm1thv2t | -0.031 | 0.008 | (3.64+/-0.18)e2 | 2.90 +/- 3.65 | K | MUPS 1 THRUSTER VALVE 02 TEMP | |
| pm2thv2t | -0.073 | 0.022 | (3.30+/-0.51)e2 | 6.63 +/- 7.82 | K | MUPS 2 THRUSTER VALVE 02 TEMP | |
| pline02t | -0.022 | 0.006 | (3.49+/-0.14)e2 | 2.71 +/- 3.39 | K | PROP LINE TEMP 02 | |
| pline03t | -0.013 | 0.006 | (3.39+/-0.14)e2 | 2.65 +/- 2.42 | K | PROP LINE TEMP 03 | |
| pline04t | -0.014 | 0.005 | (3.30+/-0.11)e2 | 3.60 +/- 3.04 | K | PROP LINE TEMP 04 | |
Quarterly Trends
- PCAD FTS Temperature and Gradient
| Previous Quarter | |||||||
| MSID | MEAN | RMS | DELTA/YR | DELTA/YR/YR | UNITS | DESCRIPTION | |
| ohrthr27 | -0.004 | 3.497e-04 | (2.98+/-0.01)e2 | 0.25 +/- 0.22 | K | RT 20 : PERISCOPE | |
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| ohrthr42 | -0.009 | 3.294e-04 | (2.98+/-0.01)e2 | 0.11 +/- 0.17 | K | RT 133: PERISCOPE | |
| ohrthr43 | -0.010 | 4.128e-04 | (2.98+/-0.01)e2 | 0.18 +/- 0.25 | K | RT 134: PERISCOPE | |
| oobagrd3 | 6.172e-04 | 1.035e-04 | -0.41 +/- 0.24 | -0.13 +/- 0.09 | K | RT 505 TO RT 504: PERISCOPE GRADIENT MONITOR | |
| oobagrd6 | -7.999e-05 | 3.493e-06 | 0.14 +/- 0.01 | -0.00 +/- 0.00 | K | RT 507 TO RT 506: PERISCOPE GRADIENT MONITOR | |
- SIM Temperature
| Previous Quarter | |||||||
| MSID | MEAN | RMS | DELTA/YR | DELTA/YR/YR | UNITS | DESCRIPTION | |
| 3btu_bpt | 0.009 | 0.002 | (2.71+/-0.05)e2 | -2.47 +/- 1.55 | K | BTU BASEPLATE (+X)), ABORT HTR TSC2 | |
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| 3tsmxcet | -0.034 | 0.019 | (2.43+/-0.44)e2 | -0.53 +/- 5.05 | K | -X TURTLE SHELL NR HRC CEA | |
| 3tsmxspt | -0.168 | 0.081 | (4.35+/-1.89)e2 | -9.43 +/- 23.34 | K | -X TURTLE SHELL NR ACIS SS | |
- SIIM Electronics
| Previous Quarter | |||||||
| MSID | MEAN | RMS | DELTA/YR | DELTA/YR/YR | UNITS | DESCRIPTION | |
| agrndadc | 2.481e-07 | 4.495e-08 | -(5.79+/-1.26)e-4 | -(7.46+/-3.06)e-5 | V | Analog fround A/D convert reading | |
|---|---|---|---|---|---|---|---|
| fatabadc | 9.140e-06 | 2.076e-05 | 4.99 +/- 0.06 | (3.60+/-20.73)e-4 | V | FA Tab Position Sensor A/D Converter | |
| n15vadc | 8.563e-07 | 1.455e-07 | -15.02 +/- 0.00 | (8.56+/-8.72)e-5 | V | -15V Power Supply A/D Converter Reading | |
| p15vadc | 1.548e-08 | 1.371e-07 | 14.96 +/- 0.00 | -(2.73+/-12.04)e-5 | V | +15V Power Supply A/D Converter Reading | |
| p5vadc | 1.109e-05 | 7.512e-07 | 4.94 +/- 0.00 | -(2.31+/-5.81)e-4 | V | +5V Power Supply A/D Converter Reading | |
| tsctabadc | -1.777e-04 | 5.981e-05 | 4.97 +/- 0.17 | -0.01 +/- 0.02 | V | TSC Tab Position Sensor A/D converter | |
Spacecraft Motions
TSC and FA Cummulative Moter Distance
HETG and LETG Cummulative Insertion Counts
HETG/LETG Insertion/Retraction Angle
Reaction Wheel Rotations
