Phase 2 Proposal Instructions for Cycle 10

3.10 Bright-Object Constraints

Several of the Scientific Instruments must be protected against over-illumination. Table 3.13 summarizes the safety restrictions by instrument. You should not propose observations which violate these guidelines. Non-linearity, saturation, or other temporary effects which may occur at substantially fainter limits than those identified below are described in the Instrument Handbooks.
Table 3.13: Bright-Object Constraints

Instrument Description

STIS The STIS MAMA (UV) detectors are subject to strict bright-object controls to prevent potentially fatal damage. Maximum permissible local and global count rates have been established for the STIS MAMA detectors, both for imaging and spectroscopy; see the STIS Instrument Handbook. These limits have been translated into extensive tables of magnitude and flux guides for the various configurations and modes; consult the STIS Instrument Handbook. Some of these limits are quite faint. All potential targets should be checked for safety with the STIS Exposure Time Calculator on the Web. Measured UV fluxes must be provided for any objects within 1 magnitude of the spectroscopic limits; if not previously available, they must be first observed with a safe STIS mode. Magnitudes and colors, or a UV image, must be provided for all objects in the fields of proposed PRISM and MAMA direct-imaging observations, including the background fields of solar-system targets. There are no safety-related brightness limits for the STIS CCD. See the STIS Instrument Handbook for a description of saturation levels, residual charge, and other effects.

WFPC2 There are no safety-related brightness limits for the WFPC2. See the WFPC2 Instrument Handbook for a description of saturation levels, residual charge, etc.

FGS The FGS may not be used to view objects brighter than mV = 1.8. The FGS may view objects brighter than mV = 8.0 only if the neutral-density filter is in place.

NICMOS There are no safety-related brightness limits for the NICMOS. See the NICMOS Instrument Handbook for a description of saturation levels, residual charge, etc.

Instrument	Description
STIS	The STIS MAMA (UV) detectors are subject to strict bright-object controls to prevent potentially fatal damage. Maximum permissible local and global count rates have been established for the STIS MAMA detectors, both for imaging and spectroscopy; see the STIS Instrument Handbook. These limits have been translated into extensive tables of magnitude and flux guides for the various configurations and modes; consult the STIS Instrument Handbook. Some of these limits are quite faint. All potential targets should be checked for safety with the STIS Exposure Time Calculator on the Web. Measured UV fluxes must be provided for any objects within 1 magnitude of the spectroscopic limits; if not previously available, they must be first observed with a safe STIS mode. Magnitudes and colors, or a UV image, must be provided for all objects in the fields of proposed PRISM and MAMA direct-imaging observations, including the background fields of solar-system targets. There are no safety-related brightness limits for the STIS CCD. See the STIS Instrument Handbook for a description of saturation levels, residual charge, and other effects.
WFPC2	There are no safety-related brightness limits for the WFPC2. See the WFPC2 Instrument Handbook for a description of saturation levels, residual charge, etc.
FGS	The FGS may not be used to view objects brighter than mV = 1.8. The FGS may view objects brighter than mV = 8.0 only if the neutral-density filter is in place.
NICMOS	There are no safety-related brightness limits for the NICMOS. See the NICMOS Instrument Handbook for a description of saturation levels, residual charge, etc.

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