NIRISS Dark Template Parameters

JWST's NIRISS Dark Engineering template, available in the Astronomer’s Proposal Tool (APT), is used for calibration observations for the NIRISS instrument. 

Introduction

Purple text indicates the parameter is Limited Access.

Boldface italics type indicates the name of an APT parameter or a value for a parameter.

(warning)Red text indicates restrictions on a parameter.

(red star) Black text indicates an important note.

Brown text indicates notes for the developers.

Green text indicates the name of the parameter used by Commanding.

Items in brackets - <value> - are required values.

Items in square brackets - [<value>] - are optional.

These parameters are required to obtain Dark observations.  Darks can be obtained with NIRISS as parallel observations (i.e. when another primary instrument is conducting science observations).

The NIRISS Dark template consists of the following parameters:

FieldDetailsValues Notes
General Information   
Observation Numberassign observation number

number



Observation Label provide observation labeltextoptional
Observation Commentsprovide observation commentstextoptional
Special Requirementsspecify special requirementschoose from listif needed
Template Specific Information   

Subarray

select Subarray

choose from list


Readout Patternspecify readout patternNIS, NISRAPID
Number of Groups/Integration specify number of groups per integrationnumber 
Number of Integrations/Exposure specify number of integrations per exposurenumber 

General Information 

The following parameters are generic to all templates, and are not discussed in this article: Observation Number,  Observation Label, Observations Comments,    and Special Requirements.

Subarray 

SUBARRAY [SUBARRAY] = FULL, SUB64, SUB80, SUB128, SUB256,WFSS64R, WFSS64C, WFSS128R, WFSS128C, SUBSTRIP96, SUBSTRIP256

This parameter specifies the region of the SCA that is to be read out; see Table 1 for details.

Table 1. Subarrays for NIRISS Dark Image  

Subarray

Size (cols x row)

Col corner

 Row corner

FULL

2048 x 2048

1

1

SUB64

64 x 64

1

1

SUB80

80 x 80

1969

925

SUB128

128 x 128

1

1

SUB256

256 x 256

1

1

WFSS64R

2048 x 64

1

1

WFSS64C

64 x 2048

1

1

WFSS128R

2048 x 128

1

1

WFSS128C

128 x 2048

1

1

SUBSTRIP96

96 x 2048

151

1

SUBSTRIP256

256 x 2048

1

1

SUBTAAMI64 x 641905932
SUBTASOSS64 x 6481963
SUBAMPCAL1792 x 5122571537

Readout Pattern  

READOUT PATTERN [READOUT PATTERN] = NIS, NISRAPID

This field specifies the readout pattern to be used to obtain the data. NIS is used for faint targets, while NISRAPID is used for bright targets or scenes with high backgrounds.         

Number of Groups/Integration 

NUMBER OF GROUPS/INTEGRATION [NGROUPS] specifies the number of groups in an integration. (warning)For readout pattern NIS, the range is 1-200, while for NISRAPID the range is 1-800.

Number of Integrations/Exposure  

NUMBER OF INTEGRATIONS/EXPOSURE [NINTS] field specifies the number of times the integration is repeated. (warning)The range is 1-65535.

Change log

The initial version of this chapter was provided by Lily Liu.


Version 6 (October 20, 2021)

  1. Editorial change (fixed typo).


Version 5 (April 18, 2019)

  1. Editorial change (moved change log to main article).


Version 4 (September 21, 2017)

  1. PR 87947 - add 3 new subarrays


Version 3 (September 18, 2017)

  1. PR 87895 - updated Exposure field labels to Groups/Integration and Integrations/Exposure


Version 2 (January 4, 2017)

  1. PR 85591 - updated Subarray name for SUBSTRIP96 and Row Corner for SUB80


Version 1 (October 26, 2016)

This is the converted Word File from Chapter 49.