CALBLOCK-PV-034: VIS Charge Injection Timing

Parent requirement

R-CAL-B-VS-4355
R-CAL-B-VS-4356

Observation configuration file

ocf_CALBLOCK-PV-034_CI-DELAY.csv
ocf_CALBLOCK-PV-034_CI-DARKS-15.csv

Scheduling

In case of failure, repeat as soon as possible. This calibration should be taken when radiation damage to the detectors is still very low.

  • CI-DELAY variant:

Execute 2 sequence blocks during PV phase; each block consisting of 4x the CIL sequence listed below.

One block to be executed at the beginning with CALBLOCK-PV-028, and one at the end of PV phase.

  • CI-DARKS-15 variant:

Run once for each particular SAA/AA spacecraft attitude of interest.

Time-critical

The observations should be performed as close in time as possible to the ROS-type (32 CIL pattern) nominal charge injection block CALBLOCK-PV-028: VIS CTI Charge Injection.

Dependencies

None

Objective

  • CI-DELAY variant:

Add additional information about trap capture and release times by varying the charge injection speed.

  • CI-DARKS-15 variant:

These observations provide verification of straylight signal reconstruction in Charge Injection images. The reconstruction will be derived from a standard Dark image with the same straylight attitude. For details, refer to the CI-DARK-AB variant Objective of CALBLOCK-PV-028: VIS CTI Charge Injection.

Observations

  • CI-DELAY variant:

THere are 6 different combinations of ID_DELAY and TOI_CHG_INJ to be executed:

Table 69: Variable charge injection data (PV). CSV file

# Number

ID_Delay [us]

TOI_CHINJ [us]

1

128

86

2

191

114

3

191

143

4

381

250

5

762

500

6

1500

1000

Constant CIL parameters for all ID_DELAY and TOI_CHG_INJ combinations:

  • EXPTIME = 1 ms

  • DAC_IDL = 10.5 V

  • ID_WIDTH = 60 us

  • CHG_INJ_ON = 260

  • CHG_INJ_OFF = 1790

  • VSTART_CHJ_INJ = 16

  • VEND_CHJ_INJ = 2066

  • VSTART = 0

  • VEND = 2086

  • \(30\mu{\rm s}\) DWELL (CHINJ_RoDly) = OFF

  • DAC_IG1 = 4.75 V

  • DAC_IG2 = 6 V

The 6 different CIL sequences are interleaved with a BIAS to constitute a timing scan. The scan is repeated 4x in a single sequence block:

Observation instructions 50: Charge Injection Timing Scan, single sequence block. This sequence block is to be executed twice during PV.
Repeat 4x:
   BIAS, CIL-1, CIL-2, CIL-3
   dither (for HGA repointing)
   BIAS, CIL-4, CIL-5, CIL-6
   dither (for HGA repointing)

  • CI-DARKS-15 variant:

The timing parameters (ID_DELAY, TOI_CHG_INJ) affect the CI-Dark outcome, and hence we have 5 different CI parameter configurations 1, 2, 3, 4 and 5.

These configuration correspond to the first 5 CI timing configurations as given above. Entry 6 in the table is the same as configurations B in the CI-DARK-AB variant of CALBLOCK-PV-028: VIS CTI Charge Injection, and will not be repeated in this CALBLOCK.

At each pointing, take a Bias, 2x Darks, and 4x charge injections (CI) frames with no charge injected (“CI-Dark”). The straylight dependence will be studied in depth in CALBLOCK-PV-028: VIS CTI Charge Injection, which require >3 straylight levels. Here we study the timing dependence, hence a minimal set of straylight levels is used.

Observation instructions 51: Timing-related Charge-Injection Dark (CI-Dark) sequence.
for each AA = [0.0, -2.5, -5.5]:
   BIAS, DARK, DARK, CIDark-1, CIDark-1, CIDark-1, CIDark-1
   dither
   BIAS, DARK, DARK, CIDark-2, CIDark-2, CIDark-2, CIDark-2
   dither
   BIAS, DARK, DARK, CIDark-3, CIDark-3, CIDark-3, CIDark-3
   dither
   BIAS, DARK, DARK, CIDark-4, CIDark-4, CIDark-4, CIDark-4
   dither
   BIAS, DARK, DARK, CIDark-5, CIDark-5, CIDark-5, CIDark-5
   dither

Fulfilling

Complements CALPRODUCT-VS-005: VIS CTI Charge Injection Lines

Targets and pointing constraints

Pointing: Straylight suppression as per MOCDA-SYS-003, and specifically \({\rm SAA} > 92\) for CI-DELAY variant.

Pointing: Straylight variability for CI-DARKS-15 variant: \({\rm AA} = [-5.5, -2.5, 0.0]\).

No specific target required.

Instrument configuration

Instrument: Wide survey

Inter-operability constraints

None

In-orbit duration

In-orbit Duration: 16.1 h + dither (x31)

CI-DELAY Variant: 2.5 h + dither (x8) [single block duration]

A block must be repeated once later in the PV phase, for a total of two blocks.

CI-DARKS-15 Variant: 2659s x 5 x 3 = 11.1 h + dither (x15)

Note that 66s of CDPU processing time has been absorbed into each dither/slew.

Data volume

Total = 28310 MB

(2*4+15)*VB  = 5750 MB for the Bias
6*VC(330MB) * 4 = 7920 MB for the CI
15*VC(330MB)  = 4950 MB for the CI-Dark
30*VD = 9690 MB for the Darks

Processing input

Ground Processing Input Data:

Data Description: 8 BIAS (LE1) and 24 CIL (LE1) [CI-DELAY variant]

15 BIAS, 30 DARKs, 60 CI-Darks (LE1)

Processing method

Binning, Cosmic Ray Flagging, CTI correction tools in VIS_CTI PE.

Processing output

Master Charge Injection Non-uniformity Pattern.

Statistics on Charge Injection temporal consistency.

Initial CTI model.

Required accuracy, constraints

R-CAL-B-VS-4354
R-CAL-B-VS-4355
R-CAL-B-VS-4356
R-CAL-B-VS-4358

Processing tools

VIS_CTI IOT analysis

Quality control parameters

DataModel: https://gitlab.euclid-sgs.uk/

Contact person

VIS instrument scientist