MTA Monitoring Report 10/15/04 - 10/21/04

Archive of all weekly reports

Archive of monthly reports

Radiation

Quiet.

Detrended CTI

CTI page was updated. The top panel shows an example of detrended CTI measurements from the front illuminated CCD3 Node 0. The top plot is all data points without any temperature dependency correction. The middle plot is data with the focal temperature equal or colder than -119.7 C, and the integration time longer than 7,000 sec. The bottom plot is all data with the temperature correction.

The values quoted below are temperature factor corrected ones.
Average of ACIS-I CCDs (MnKa) slope 5.556e-9 CTI/day
Detrended slope 6.510e-9 CTI/day

ACIS Warm Pixels

We display all bad pixels 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 a computational artificial effect due to boundaries.


ACIS Focal Plane Temperature

For this period, 6 peaks are observed.

SIM Movements

8 TSC moves this period
weekly average time/step 0.00125 s
mission average time/step 0.00137 s

Telemetry

IRUs


Recent Observations

"Prob" means that there was probably bad time data included in the manual runs. This will probably be corrected in future AP processing.

OBSID DETECTOR GRATING TARGET ANALYSIS ACA
6146 ACIS-S NONE Abell426 OK Prob
6145 ACIS-S NONE Abell426 OK OK
4692 ACIS-S NONE NGC3384 OK OK
4560 ACIS-S HETG IGRJ18410-0535 OK /OK OK
4599 ACIS-I NONE RCW103 OK Missing
4953 ACIS-S NONE Abell426 OK OK
4951 ACIS-S NONE Abell426 OK OK
4478 ACIS-I NONE IC1396-N OK OK
4952 ACIS-S NONE Abell426 OK OK

Trending

There is a concern about the cooling of the propulsion fuel lines number 3 and 4.
Summary (from the FOT):
PLINE03T and PLINE04T have begun to dip below their caution low limits. The violations always occur on the first heater cycle after a maneuver to a cold attitude. The previous attitude varies. PLINE03T is on the MUPS-2, A-side feedline and can be isolated with Isovalve 3 (Open, must be open for MUPS A-side operation). PLINE04T is on the RCS-2, A-side feedline and is isolated with Isovalve 8 (Closed). The Long Term Trending shows a decline in the lowest temperatures on PLINE03 and PLINE04.

PLINE02T is on the same circuit as PLINE03T and PLINE04T. The thermostat that controls the heaters is near PLINE02T, which does not show the same trend in the minimum temperature. PLINE02T and the thermostats for the heater circuit of concern are on the MUPS-1 feedlines. So the thermostats controlling the circuit are on the -Y/-Z side of the spacecraft, while the lines of concern are on the +Y/-Z side. It was anticipated, prior to launch, that the propulsion components on the ?Y side would be cooler than the +Y side. For PLINE03T, this is the case at forward sun attitudes, but not at tail-sun attitudes. At tail-sun the +Y side cools faster and further than the ?Y side, allowing PLINE03T to dip below the heater set point for the circuit. PLINE04T was generally warmer than PLINE02T for the first few years of the mission, but this is no longer the case. Therefore, on a maneuver to a tail sun attitude, PLINE04T starts out cooler than PLINE02T and continues to be cooler until the heater turns on. This allows PLINE04T to dip below the heater set point for the circuit until PLINE02T cools enough for the heater to turn on.

The following plots show the minimum observed average (over 5 minutes) temperatures on PLINE03 and PLINE04 since launch. The actual minimums are lower, as the averaging process raises them. MTA databases have a small gap which we are filling. More complete data is available via the FOT OCC website.

This Week's focus is HRC.

Trends last reported on July 29.

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