Phase 2 Proposal Instructions for Cycle 10

3.12 Generic Targets List [Generic_Targets]

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Generic targets are those that during Phase II can only be described in terms of astronomical characteristics or general location in the sky. This category is used only for Targets of Opportunity and parallel exposures.

For parallel exposures, both pure-parallel and coordinated-parallel (see Chapter6:Parallel Science Exposures), the pointing is determined by the primary observation, and the specification of a generic target for the parallel exposure denotes a region within which the parallel aperture is expected to point. If the parallel pointing does not matter and the intent is simply to sample whatever the parallel aperture happens to detect, it is not necessary to define a generic target; instead the special target ANY should be used (see5.7Target Name [Target_Name]).

Note: Generic Target region coordinates are assumed to be in the J2000 reference frame.

3.12.1 Target Number(s) [Target_Number]

Generic targets should be given individual names and numbers just like fixed targets; however, it is possible to enter a range of target numbers associated with a single target name. If a range is specified, the number of targets must reflect the number of separate fields that will be observed. For example, if WFPC2 observations of 10 different fields, all named QSO-SURVEY-FIELD, are required for a quasar search, the value of the Target_Number keyword would be 1Ð10.

3.12.2 Target Name [Target_Name]

A descriptive name must be provided. If a name cannot be specified in advance, a provisional name should be supplied. When the actual observation is made, a more specific name will be added to the target designation. Either the provisional name or the updated name can then be used for archival searches (e.g., SN might be the provisional name, while SN-1995D might be the updated name). A unique target name must be assigned to each generic target.

3.12.3 Target Description [Description]

See 3.3Target Description [Description].

3.12.4 Flux Data [Flux]

See 3.9Flux Data [Flux].

Flux data are not required for pure parallel observations of generic targets.

3.12.5 Comments [Comments]

See 3.11Comments [Comments].

3.12.6 Generic Target Specifications

A way to specify generic celestial regions and target lists in a machine-readable fashion is described below, and should be used for the Generic Targets List. It is important that these instructions be followed in order for pure parallels with generic targets to be schedulable.

Two types of generic target specifications are permitted:

• Region generic targets: a celestial region specified in one of three coordinate systems
• Target Lists: lists of fixed or generic targets

The Selection Criteria column should use the syntax specified below whenever the selection criteria can be fully specified by a celestial region in one of the supported coordinate systems, or by a list of fixed or generic targets.

In all other cases a text description should continue to be provided after the ÒOther:Ó header.

Region Generic Targets

Three coordinate systems are supported:

• Equatorial: right ascension (RA) and declination (DEC)
• Galactic: Galactic longitude (LII) and Galactic latitude (BII)
• Ecliptic: ecliptic longitude (LAMBDA) and ecliptic latitude (BETA)

Regions may be any of:

1. ÒRectangularÓ regions, i.e. bounded by latitude and longitude limits in the appropriate coordinate system
2. Circular regions, specified as within some angular limit of a point specified in any of the three supported coordinate systems
3. Polar caps or equatorial bands in any supported coordinate system

The following table provides examples of each of these types of region specifications. Note that the same rules for specifying RA and Dec apply as for fixed targets (See Equatorial Coordinates)

Region type	Equatorial coordinates	Galactic coordinates	Ecliptic coordinates
rectangular	RA = 5H 30M 0S +/- 180M,	LII = 45D+/-10D,	LAMBDA = 56D+/-5D,
	DEC = -65D +/- 10D	BII = 15D+/-10D	BETA = 60D+/-15D
circular	RA = 1H 30M 0S,	LII = 0D,	LAMBDA = 45D,
	DEC = -15D, R=10D	BII = 15D, R=5D	BETA = -15D, R = 5.5D
polar cap	DEC > 60D	BII < -30D	BETA > 10D
both polar caps	ABS_DEC > 60D	ABS_BII > 30D	ABS_BETA > 10D
equatorial band	ABS_DEC < 10D	ABS_BII < 30D	ABS_BETA < 45D

 

Note that for rectangular and circular regions, the syntax is identical to that of fixed target regions except that the indicator REGION is omitted, and galactic and ecliptic coordinates are allowed.

Target Lists

In some cases it may be desirable to specify as a Generic Target any of a list of Fixed Target positions or Generic Target regions. In this case the fixed targets should be provided as usual on the Fixed Target List, and the generic target regions should be specified as above on the Generic Target List. Then a new generic target can be defined with Selection Criteria specified by:

TARGETS = <target-number-list>

This will be taken to indicate that any of the targets in <target-number-list> are suitable as targets. Note that target numbers are required to be unique across all targets in a proposal, whether on the Fixed, Generic, or Solar System Target Lists.

This type of target is particularly useful when a known list of objects of interest is available, and it is desired to observe one of these objects with an imaging SI when a primary exposure with a spectrograph is positioned appropriately nearby.