MTA Monitoring Report 04/13/18 - 04/19/18

Archive of all weekly reports
Archive of monthly reports

Radiation

Quiet

Detrended CTI

Although we prefer to quote CTI values of the cleanest data (FT <= -119.7 C, int time > 7000sec), the data that fulfills these conditions are getting rare. We now quote CTI based on temperature corrected data for Focal plane temperature <= -118.5 C).

The unit is now CTI/year not CTI/day.

ACIS Warm Pixels

We display all bad pixels that have showed up in past, and, if any, previously unknown bad pixels appeared in the last 14 days. We also list hot pixels (defined as 1000 above the average of bias background). Warm columns 509-514 are probably due to boundaries.

New definitions of warm pixels and flickering pixels (May 15, 2014). If a pixel displays the level beyond a threshold for more than 70% of the time in the past two weeks, the pixel is categorized as a "warm" pixel. If a pixel is above the threshold more than 30% of time but less than 70% of the time in the past two weeks, the pixel is categorized as a "flickering" pixel.

ACIS Focal Plane Temperature

For this period, 11 peaks are observed.

Day (DOY)	Temp (C)	Width (Days)
103.27	-114.49	0.30
103.88	-115.39	0.61
104.37	-114.72	0.43
104.78	-113.57	0.68
105.59	-113.48	0.57
105.83	-115.41	0.16
106.6	-115.26	0.71
107.18	-116.17	0.46
107.7	-115.86	0.53
108.21	-115.44	0.48
108.68	-118.28	0.43

Weekly focal plane temperature with sun angle, earth angle, and altitude overplotted. Sun angle is the solar array angle, that is the angle between the sun and the optical axis (+X axis). The earth angle is the angle between earth and the ACIS radiator (+Z axis). Altitude varies from 34 kkm to 128 kkm.

SIM Movements

7 TSC moves this period

weekly average time/step	0.00132 s
mission average time/step	0.00136 s

Telemetry

New violations or new extrema are shown in blue cells.

IRUs

• Gyro Bias Drift
• Gyro Bias Drift Histogram

Recent Observations

Trending

This week's focus is Ground Computations

Last reported on Jan 25.

Only the most interesting or representative msids are shown below. For a full listing choose the bulletted link.

Min/max envelopes in dark blue appear on the trending plots. The envelopes are 4th degree fits to the monthly minimum and maximum values for each MSID. The final polynomial form and binning are still being experimented with. We will soon add to the trending pages a report of the fits and predictions they give on future limit violations. The light blue curve is our original smoothing of all the data over 30 day moving boxcars. The green/yellow line is a linear fit to all the data; the break occurs at a limit change.

• ACIS Electronics

Computed ACIS Electronics
MSID	MEAN	RMS	DELTA/YR	DELTA/YR/YR	UNITS	DESCRIPTION
1DPPWRA	38.17	1.99	-2.802e-01	3.418e-01	W	DPA POWER A
1DPPWRB	34.21	1.54	-3.132e-01	5.948e-02	W	DPA P WER B

• Computed SIM Thermal

Computed SIM Theraml
MSID	MEAN	RMS	DELTA/YR	DELTA/YR/YR	UNITS	DESCRIPTION
FLEXADIF	65.86	1.93	-9.429e-01	-2.333e-02	POINT	DIFF FLEX A & SET
FLEXBDIF	59.70	1.91	-9.292e-01	1.866e+00	POINT	DIFF FLEX B & SET
FLEXCDIF	74.29	6.90	-2.565e+00	4.637e+00	POINT	DIFF FLEX C & SET

If you have any questions, please contact: swolk@head.cfa.harvard.edu