M&TA December 2025 Monthly Report

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

Please check more detail plots at Telemetered Photon Dose Trend page.

December registered-photon-map in fits

December Dose Map

TOTAL

CCD I3

CCD S3

Statistics:
# IMAGE     NPIX     MEAN        RMS        MIN     MAX
ACIS_dec25 6004901       5.005         8.475           0.0      494


I2 node 0  262654	3.557868	2.167352	0.0	 41.0
I2 node 1  262654	3.939513	2.511312	0.0	393.0
I2 node 2  262654	4.770716	3.192166	0.0	 66.0
I2 node 3  262654	7.066396	6.632893	0.0	448.0

I3 node 0  262654	11.637359	11.537262	0.0	434.0
I3 node 1  262654	6.768648	4.073572	0.0	 82.0
I3 node 2  262654	5.000035	2.697366	0.0	 60.0
I3 node 3  262654	4.381016	2.574861	0.0	494.0

S2 node 0  262654	5.326720	5.132274	0.0	 88.0
S2 node 1  262654	5.487103	5.318587	0.0	250.0
S2 node 2  262654	6.660401	9.113385	0.0	258.0
S2 node 3  262654	6.619198	7.769172	0.0	452.0

S3 node 0  262654	8.907667	11.948845	0.0	239.0
S3 node 1  262654	9.335205	13.190150	0.0	207.0
S3 node 2  262654	9.888224	16.260911	0.0	215.0
S3 node 3  262654	8.676498	14.574555	0.0	198.0

Jul 1999 - Dec 2025 registered-photon-map in fits

Cumulative Dose Map

TOTAL

CCD I3

CCD S3


Statistics:
 IMAGE     NPIX      MEAN        RMS           MIN      MAX
ACIS_total   6004901       2762.126         3481.202           0.0   169725


I2 node 0  262654	2397.653326	487.730586	511.0	16130.0
I2 node 1  262654	2530.431689	714.608916	524.0	167719.0
I2 node 2  262654	2559.754380	545.865331	548.0	17921.0
I2 node 3  262654	2567.615266	672.225945	507.0	37733.0

I3 node 0  262654	2783.007529	703.750933	507.0	16803.0
I3 node 1  262654	2851.622248	1760.811181	534.0	56099.0
I3 node 2  262654	2555.382234	480.606163	501.0	15660.0
I3 node 3  262654	2529.706080	517.264339	482.0	37204.0

S2 node 0  262654	3221.120569	520.099263	1733.0	22689.0
S2 node 1  262654	3422.131696	782.336050	1912.0	22359.0
S2 node 2  262654	3795.820083	785.380037	2326.0	34296.0
S2 node 3  262654	3751.951859	645.020652	2045.0	89344.0

S3 node 0  262654	5704.602202	3077.575554	2515.0	55601.0
S3 node 1  262654	6927.652918	2411.680963	0.0	83602.0
S3 node 2  262654	5662.647695	1385.927470	2669.0	27742.0
S3 node 3  262654	4454.246168	784.575786	2673.0	26839.0

Integrated Exposure Maps of Last 12 Months

Sep 2025	Jun 2025	Mar 2025	Dec 2024

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

Dec 2025 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

This page shows scientific instrument background data based on Acis observations. A source region file is generated using get_srcregions and then the input event file is filtered using the regions in that file to remove the sources.

HRC

DOSE of Central 4K Pore-Pairs

Please refer to Maximum Dose Trends for more details.

Dec HRCI Dose in fits

IMAGE                NPIX      MEAN    STDDEV      MIN       MAX
HRCI_12_2025.fits  16777216	0.006 	0.075 	0.000 	3.000

AUG 1999 - Dec 2025 HRCI Dose in fits

IMAGE                       NPIX      MEAN    STDDEV      MIN       MAX
HRCI_08_1999_12_2025.fits  16777216	na	na	na	na

Dec HRCS dose fits image - no observations

 
No Data

AUG 1999 - Dec 2025 HRCS Dose in fits

IMAGE                       NPIX      MEAN    STDDEV      MIN       MAX
HRCS_08_1999_12_2025.fits  16777216	na	na	na	na

Max dose trend plots corrected for events that "pile-up" in the center of the taps due to bad position information.

HRC I: Integrated Exposure Maps of Last 12 Months

Sep 2025	Jun 2025	Mar 2025	Dec 2024

HRC S: Integrated Exposure Maps of Last 12 Months

Sep 2025	Jun 2025	Mar 2025	Dec 2024

TOP

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

ACA Trending - May 2020

ACIS
ACIS
HRCI
HRCI

Fid Light Drift

Fid light positions on ACA drift with time. The drift trends of Fid light 2 with ACIS-I and ACIS-S configurations are shown below.

The top panel shows Fid light 2 drift in ACENT I (app. along with -Y axis), and the bottom panel shows that in ACENT J (app. along with Z axis). The unit is a pixel, and one pixel is approximately 0.5 arcsec. The slope listed at the top right corner is the change in a position per year (arcsec/yr). The vertical line on DOM = 1411 (Jun 1, 2003) indicates a transition date of use of IRU-1 to IRU-2.
See also Tom Aldcroft's updated page: https://cxc.cfa.harvard.edu/mta/ASPECT/fid_drift

Fid 2 (ACIS-I)

Fid 2 (ACIS-S)

Fid 8 (HRC-I)

Fid 12 (HRC-S)

Gyro Bias Drift

TOP

Radiation History

Radiation Count Rates of Dec 2025

Sun Spot History (See:NOAA Page)

TOP

Critical Trends

ACIS Temperatures - Daily Maximums
MSID		MEAN	RMS	DELTA/YR	DELTA/YR/YR	UNITS	DESCRIPTION
1pdeaat		0.042	0.002	(3.04+/-0.06)e2	0.69 +/- 1.71	K	PSMC DEA PS A TEMP

HRMA Computed Averages - Daily Maximums
MSID		MEAN	RMS	DELTA/YR	DELTA/YR/YR	UNITS	DESCRIPTION
obaavg		0.025	0.001	(3.01+/-0.03)e2	2.29 +/- 0.84	TEMP	OBA/TFTE

EPHIN Temperatures - Daily Maximums
MSID	MEAN	RMS	DELTA/YR	DELTA/YR/YR	UNITS	DESCRIPTION
teio	0.023	0.009	(3.35+/-0.21)e2	-1.91 +/- 3.71	K	EPHIN ELECTRONICS HOUSING TEMP
tephin	0.030	0.004	(3.41+/-0.09)e2	4.00 +/- 2.87	K	EPHIN SENSOR HOUSING TEMP

S/C Main Temperatures - Daily Maximums
MSID	MEAN	RMS	DELTA/YR	DELTA/YR/YR	UNITS	DESCRIPTION
tcylfmzm	0.043	0.005	(3.24+/-0.11)e2	1.41 +/- 2.08	K	CNT CYL TEMP:-Z SIDE UNDER LAE-1
tcylfmzp	0.044	0.004	(3.26+/-0.10)e2	1.41 +/- 1.84	K	CNT CYL TEMP:-Z SIDE UNDER LAE-2

S/C Ancillary Temperatures - Daily Maximums
MSID	MEAN	RMS	DELTA/YR	DELTA/YR/YR	UNITS	DESCRIPTION
tfssbkt1	0.043	0.012	(3.58+/-0.29)e2	3.60 +/- 4.66	K	FSS BRAC
tfssbkt2	0.044	0.013	(3.53+/-0.32)e2	2.06 +/- 4.39	K	FSS BRAC
tsctsf1	0.041	0.003	(3.30+/-0.06)e2	5.93 +/- 2.16	K	SC-TS FITTING -1 TEMP
tsctsf6	0.031	0.003	(3.30+/-0.06)e2	7.25 +/- 2.30	K	SC-TS FITTING -6 TEMP

MUPS - Daily Maximums
MSID	MEAN	RMS	DELTA/YR	DELTA/YR/YR	UNITS	DESCRIPTION
pm1thv1t	0.053	0.008	(3.59+/-0.18)e2	-0.04 +/- 3.62	K	MUPS 1 THRUSTER VALVE 01 TEMP
pm2thv1t	0.222	0.016	(3.40+/-0.39)e2	2.54 +/- 5.42	K	MUPS 2 THRUSTER VALVE 01 TEMP
pm1thv2t	0.055	0.008	(3.62+/-0.18)e2	1.00 +/- 3.90	K	MUPS 1 THRUSTER VALVE 02 TEMP
pm2thv2t	0.123	0.022	(3.27+/-0.52)e2	0.72 +/- 8.31	K	MUPS 2 THRUSTER VALVE 02 TEMP
pline02t	0.053	0.006	(3.46+/-0.14)e2	-0.89 +/- 3.33	K	PROP LINE TEMP 02
pline03t	0.042	0.006	(3.37+/-0.14)e2	0.52 +/- 2.44	K	PROP LINE TEMP 03
pline04t	0.054	0.005	(3.27+/-0.11)e2	-3.65 +/- 2.87	K	PROP LINE TEMP 04

Quarterly Trends

HRMA Struts

Previous Quarter
MSID	MEAN	RMS	DELTA/YR	DELTA/YR/YR	UNITS	DESCRIPTION
4rt584t	0.018	7.515e-04	(3.04+/-0.02)e2	1.58 +/- 0.58	K	RT 584 - STRUT TEMP
4rt585t	0.020	7.507e-04	(3.04+/-0.02)e2	1.29 +/- 0.57	K	RT 585 - STRUT TEMP
4rt586t	0.018	6.258e-04	(3.00+/-0.02)e2	0.95 +/- 0.47	K	RT 586 - STRUT TEMP
4rt587t	0.015	4.871e-04	(2.93+/-0.01)e2	0.81 +/- 0.36	K	RT 587 - STRUT TEMP
4rt597t	0.023	0.002	(3.13+/-0.04)e2	2.04 +/- 1.17	K	RT 597 - TFTE TEMP
4rt598t	0.025	0.002	(3.13+/-0.04)e2	1.75 +/- 1.19	K	RT 598 - TFTE TEMP

OB Forward Bulkhead

Previous Quarter
MSID	MEAN	RMS	DELTA/YR	DELTA/YR/YR	UNITS	DESCRIPTION
4rt705t	0.021	8.792e-04	(2.94+/-0.02)e2	0.67 +/- 0.73	K	RT 705 - OB BUL
4rt706t	0.021	8.906e-04	(2.93+/-0.02)e2	0.90 +/- 0.73	K	RT 706 - OB BUL
4rt707t	0.022	8.885e-04	(2.96+/-0.02)e2	0.75 +/- 0.73	K	RT 707 - OB BULKHEAD TEMP
4rt708t	0.023	9.759e-04	(3.01+/-0.02)e2	0.83 +/- 0.79	K	RT 708 - OB BULKHEAD TEMP
4rt709t	0.024	0.001	(3.03+/-0.03)e2	0.81 +/- 0.85	K	RT 709 - OB BULKHEAD TEMP
4rt710t	0.026	0.001	(3.05+/-0.03)e2	1.19 +/- 0.91	K	RT 710 - OB BULKHEAD TEMP

HRMA Thermal

Previous Quarter
MSID	MEAN	RMS	DELTA/YR	DELTA/YR/YR	UNITS	DESCRIPTION
4rt568t	0.021	9.607e-04	(3.02+/-0.02)e2	1.67 +/- 0.74	K	RT 568 - HRMA TEMP
4rt569t	0.010	2.714e-04	(2.98+/-0.01)e2	0.35 +/- 0.16	K	RT 569 - HRMA TEMP
4rt570t	0.006	1.428e-04	(2.96+/-0.00)e2	0.11 +/- 0.07	K	RT 570 - HRMA TEMP
4rt575t	0.024	0.001	(3.07+/-0.03)e2	1.85 +/- 0.95	K	RT 575 - OB CONE TEMP
4rt576t	0.022	9.642e-04	(2.97+/-0.02)e2	1.39 +/- 0.77	K	RT 576 - OB CONE TEMP
4rt578t	0.028	0.002	(3.06+/-0.04)e2	1.12 +/- 1.15	K	RT 578 - OB CONE TEMP

Spacecraft Motions

TSC and FA Cummulative Moter Distance

HETG and LETG Cummulative Insertion Counts

HETG/LETG Insertion/Retraction Angle

Reaction Wheel Rotations

TOP

Links to Past Monthly Reports

Year Month

2025 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov

2024 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2023 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2022 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2021 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2020 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2019 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2018 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2017 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2016 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2015 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2014 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2013 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2012 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2011 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2010 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2009 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2008 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2007 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2006 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2005 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2004 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2003 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2002 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2001 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2000 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

1999 Jul Aug Sep Oct Nov Dec

Back to SOT page
If you have any questions about this page, please contact swolk@head.cfa.harvard.edu.

Year	Month
2025	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov
2024	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2023	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2022	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2021	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2020	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2019	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2018	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2017	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2016	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2015	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2014	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2013	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2012	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2011	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2010	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2009	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2008	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2007	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2006	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2005	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2004	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2003	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2002	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2001	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2000	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
1999							Jul	Aug	Sep	Oct	Nov	Dec

- M&TA MONTHLY REPORT -

December 2025

OUTLINE

Configuration/Radiation Overview for December 2025