NIRISS Internal Flat Template Parameters
JWST's NIRISS Internal Flat 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.
Red text indicates restrictions on a parameter.
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 used to define each lamp exposure in an observation. Note that this type of observation cannot be obtained as a parallel to normal science observations, but can be in parallel with slews.
The NIRISS Internal Flat template consists of the following parameters:
| Field | Details | Values | Notes |
|---|---|---|---|
| General Information | |||
| Observation Number | assign observation number | number | |
| Observation Label | provide observation label | text | optional |
| Observations Comments | provide observation comments | text | optional |
| Mosaic Properties | specify mosaic parameters | number | if needed |
| Special Requirements | specify special requirements | choose from list | if needed |
| Template Specific Information | |||
| select target name | choose from list | ||
| Pointing Type | select pointing type | PARALLEL, PRIME | |
| Filter | select filter name | choose from list | |
| Readout Pattern | select readout pattern | NIS, NISRAPID | |
| Number of Groups/Integration | specify number of groups per integration | number | |
| Number of Integrations/Exposure | specify number of integrations per exposure | number | |
| Lamp Name | select lamp name | choose from list | |
| Lamp Power | select lamp power level | choose from list | |
General Information
The following parameters are generic to all templates, and are not discussed in this article: Observation Number, Observation Label, Observations Comments, Target Name, Mosaic Properties, and Special Requirements.
Target Name
Select the TARGET NAME [TBD] from the list of targets previously entered; see list of targets. If POINTING TYPE = PARALLEL, TARGET NAME = NONE. If POINTING TYPE = PRIME, NONE is not available.
Pointing Type
POINTING TYPE = PARALLEL (default), PRIME
Note for developers: This field is not saved directly into the database.
If PRIME, make TARGET NAME required, make the default “None Selected,” and remove the NONE option (so the user is prompted to select a target). Give an error if any PARALLEL special requirement is present.
If PARALLEL, set TARGET NAME = NONE (not changeable), and add a PARALLEL SLEW ONLY special requirement. Give an error if the PARALLEL SLEW ONLY special requirement is not present.
Exposure Specifications
For each exposure to be executed, specify the FILTER, READOUT PATTERN, NUMBER OF GROUPS/INTEGRATION, NUMBER OF INTEGRATIONS/EXPOSURE, LAMP NAME, and LAMP POWER.
Filter
FILTER [FILTER] = GR700XD, F090W, F115W, F140M, F150W, F158M, F200W, F277W, F356W, F380M, F430M, F444W, F480M
This parameter specifies the filter to be used for the exposure.
Note for developers: Even though GR700XD is a grism, it will be stored in the filter table.
Readout Pattern
READOUT PATTERN [READOUT PATTERN] = NIS, NISRAPID
This field specifies the readout pattern to be used to obtain the science data. NIS is used for longer flat exposures and NISRAPID is used for shorter flat exposures.
Number of Groups/Integration
NUMBER OF GROUPS/INTEGRATION [NGROUPS] specifies the number of groups in integration. For readout pattern NIS, the range is 1-45, while for NISRAPID, the range is 1-64.
Number of Integrations/Exposure
NUMBER OF INTEGRATIONS/EXPOSURE [NINTS] field specifies the number of times the integration is repeated. The range is 1-90.
Lamp Name
LAMP NAME [LAMP] = FLAT1, FLAT2, LINE1, LINE2
This field specifies the lamp to be used during the exposure.
Lamp Power
LAMP POWER [POWER] = OFF, LEVEL1, LEVEL2, LEVEL3, LEVEL4, LEVEL5, LEVEL6, LEVEL7
This field specifies the illumination level for the chosen lamp.