11.4 Tabular Reference Data

11.4.1 Spectral Elements for WFC

Table 11.2: Spectral Elements for use with ACS/WFC Configurationa

Wheel	Position	Name	Description	Allowed Configurations
1	2	F555W	Johnson V	ACS/WFC
1	3	F775W	SDSS i	ACS/WFC
1	4	F625W	SDSS r	ACS/WFC
1	5	F550M	narrow V	ACS/WFC
1	6	F850LP	SDSS z	ACS/WFC
1	8	POL0UV	UV polarizer 0 deg	ACS/WFC
1	9	POL60UV	UV polarizer 60 deg	ACS/WFC
1	10	POL120UV	UV polarizer 120 deg	ACS/WFC
1	11	F892N	methane	ACS/WFC
1	12	F606W	broad V	ACS/WFC
1	13	F502N	O III	ACS/WFC
1	14	G800L	GRISM	ACS/WFC
1	15	F658N	Hα	ACS/WFC
1	16	F475W	SDSS g	ACS/WFC
2	2	F660N	N II	ACS/WFC
2	3	F814W	Johnson I	ACS/WFC
2	4	FR388N	O II Ramp	ACS/WFC
2	4	FR423N	O II Ramp	ACS/WFC
2	4	FR462N	O II Ramp	ACS/WFC
2	5	F435W	Johnson B	ACS/WFC
2	6	FR656N	Hα ramp	ACS/WFC
2	6	FR716N	Hα ramp	ACS/WFC
2	6	FR782N	Hα ramp	ACS/WFC
2	8	POL0V	visible polarizer 0 deg	ACS/WFC
2	10	POL60V	visible polarizer 60 deg	ACS/WFC
2	12	POL120V	visible polarizer 120 deg	ACS/WFC
2	16	FR914M	Broad Ramp	ACS/WFC
2	16	FR853N	IR Ramp	ACS/WFC
2	16	FR931N	IR Ramp	ACS/WFC
2	17	FR459M	Broad Ramp	ACS/WFC
2	17	FR647M	Broad Ramp	ACS/WFC
2	17	FR1016N	IR Ramp	ACS/WFC
2	18	FR505N	O III Ramp	ACS/WFC
2	18	FR551N	O III Ramp	ACS/WFC
2	18	FR601N	O III Ramp	ACS/WFC

a. Note: Normally only one spectral element may be specified for an exposure. The exceptions are:

1) The polarizers must be used with another spectral element. This is required to maintain focus. The UV polarizers (POL0UV, POL60UV, POL120UV) must be used with a spectral element on wheel 2 except for: POL0V, POL60V, POL120V, and any inner or outer ramp filter segment (see Table 11.4). The visible polarizers (POL0V, POL60V, POL120V) must be used with a spectral element on wheel 1 except for: F850LP, F892N, POL0UV, POL60UV, and POL120UV.

11.4.2 Permitted Filter Combinations

Only a subset of possible combinations of spectral elements are permitted. In the following tables, an "S" indicates combinations that are supported. Combinations marked with "O" are permitted ONLY for Mode = ACQ exposures and are intended for use with bright targets.

Table 11.3: Permitted WFC filter combinations for Mode = ACCUM

Filter Wheel 1 Spectral Element

F555W

F775W

F625W

F550M

F850LP

POL0UV

POL60UV

POL120UV

F892N

F606W

F502N

G800L

F658N

F475W

Filter Wheel 2 Spectral Element

F660N

F814W

FR388N

FR423N

FR462N

F435W

FR656N

FR716N

FR782N

POL0V

S

S

S

POL60V

S

S

S

POL120V

S

S

S

PR200L

F344N

FR914M

FR853N

FR931N

FR459M

FR647M

FR1016N

FR505N

FR551N

FR601N

 

11.4.3 Ramp Filter Wavelength Ranges

Table 11.4: Wavelength Ranges for the WFCRamp Filters

Name	Minimum Wavelength (å)	Maximum Wavelength (å)	WFC FOV location
FR388N	3710	4049	middle
FR423N	4049	4420	inner
FR462N	4420	4824	outer
FR505N	4824	5266	middle
FR551N	5266	5748	inner
FR601N	5748	6274	outer
FR656N	6274	6848	middle
FR716N	6848	7474	inner
FR782N	7474	8158	outer
FR853N	8158	8905	inner
FR931N	8905	9719	outer
FR1016N	9719	10609	outer
FR459M	3810	5366	middle
FR647M	5366	7574	inner
FR914M	7574	10709	middle

11.4.4 Spectral Elements for ACS/SBC

Table 11.5: Spectral Elements for use with the ACS/SBC Configuration

Wheel	Position	Name	Description
3	2	F115LP	MgF2
3	3	F125LP	CaF2
3	5	F140LP	BaF2
3	6	F150LP	crystal quartz
3	8	F165LP	Suprasil
3	9	F122M	Ly-α
3	11	PR130L	CaF2 PRISM
3	12	PR110L	LiF2 PRISM

11.4.5 Allowed Combinations of Aperture, Spectral Element & Readout

Table 11.6: Allowed Aperture, Spectral Element & Readout Combinations

Aperture	Allowed Spectral Elements1	Readout
WFC	F S	full frame2
WFC-FIX	F	full frame
WFC1	F S	full frame2
WFC1-FIX	F	full frame
WFC2	F S	full frame2
WFC2-FIX	F	full frame
WFCENTER	F	full frame
WFC1-CTE	F	full frame
WFC1-512	F	subarray fixed by STScI
WFC1-1K	F	subarray fixed by STScI
WFC1-2K	F	subarray fixed by STScI
WFC1-IRAMP	F I	full frame
WFC1-MRAMP	F M S	full frame
WFC2-MRAMP	F M S	full frame
WFC2-ORAMP	F O	full frame
WFC1-IRAMPQ	F I	subarray fixed by STScI
WFC1-MRAMPQ	F M S	subarray fixed by STScI
WFC2-ORAMPQ	F O	subarray fixed by STScI

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1

F = normal WFC filters and G800L
S = small elements (polarizers and F892N)
I = inner ramp filter segments
M = middle ramp filter segments
O = outer ramp filter segments

2

A subarray fixed by STScI will apply to WFC, WFC1, WFC2 when a small
spectral element (polarizer of F892N) is selected.