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Fine Guidance Sensor Instrument Handbook for Cycle 22 > Chapter 6: Writing a Phase II Proposal > 6.5 Proposal Logsheet Examples

6.5
This section provides several examples of RPS2 formatted proposal logsheets for the following types of investigations:
 
While formatted exposure logsheets became obsolete when APT replaced RPS2, the logsheets provided here are intended to assist proposers in to obtain a high level understanding of an FGS observing program within a single HST orbit.
6.5.1 Parallax program using FGS1r in Pos mode
Goal: Determine the parallax and proper motion of star, “OGF_1”.
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Figure 6.1 illustrates the field geometry and the orient angles of a typical FGS observation, while Table 6.8 summarizes the details of the exposures in the visit.
Figure 6.1: Example 1: Field of View at Special Orientation
OGF-7-REF1
1
The “REF” appendix is not required. Rather its use is suggested simply for book keeping purposes.

Reference/Check Star Pattern: Check Stars in this observation are REF-7, REF-11, and OGF_1. Observing sequence:
OGF_1--> 12 -- 11 -- 7 -- OGF_1 -- 11 -- 21 -- 3 -- 7 -- OGF_1
-----> 9 -- 7 -- 11 -- OGF_1 -- 21 -- 12 -- 11 -- 9 -- OGF_1
 
The Exposure Logsheet Template: The Optional_Parameters entry is missing since, for this example, all Pos mode optional parameters are DEFAULT values
Visit_Number: 1
Visit_Requirements: BETWEEN 14-MAR-1998 AND 15-MAR-1998
ORIENT -18.5D TO -19.5D FROM NOMINAL
Visit_Comments: Two Guide Star FineLock Required.Exposure_Number: 01
Target_Name: OGF_1
Config: FGS
Opmode: POS
Aperture: 1
Sp_Element: F583W
Time_Per_Exposure: 20S
Special_Requirements: SEQ 1-4 NON-INT;POS TARG -33,-60.
 
Exposure_Number: 02
Target_Name: OGF-12-REF
Config: FGS
Opmode: POS
Aperture: 1
Sp_Element: F583W
Time_Per_Exposure: 30S
Special_Requirements: SAME POS AS 1;
 
Exposure_Number: 03
Target_Name: OGF-11-REF
Config: FGS
Opmode: POS
Aperture: 1
Sp_Element: F583W
Time_Per_Exposure: 30S
Special_Requirements: SAME POS AS 1;
Comments:
 
Exposure_Number: 04
Target_Name: OGF-7-REF
Config: FGS
Opmode: POS
Aperture: 1
Sp_Element: F583W
Time_Per_Exposure: 20S
Special_Requirements: SAME POS AS 1;
Comments:
 
...and continues until the orbit is filled.
 
6-months after Visit 1, the HST Nominal Orient Angle is 180 from the Nominal HST Orientation in Visit 1. Nominal orient angle = 247, off-nominal orient angle = 228, pos targ = (+60,+33).
 
Visit_Number: 2
Visit_Requirements: BETWEEN 14-SEP-1998 AND 15-SEP-1998;
ORIENT -18.5D TO -19.5D FROM NOMINAL
Visit_Comments: Two Guide Star FineLock Required.
Exposure_Number: 01
Target_Name: OGF_1
Config: FGS
Opmode: POS
Aperture: PRIME
Sp_Element: F583W
Time_Per_Exposure: 20S
Special_Requirements: SEQ 1-4 NON-INT;POS TARG +33,+60
Comments:
Exposure_Number: 02
Target_Name: OGF-12-REF
Config: FGS
 
...Continues until the orbit is filled. Visit 3 is identical to Visit 1 except that it executes 1 year later.
Running the proposal template file through APT will inform the observer whether the syntax is correct, whether the exposures fit in an orbit and how much time is left, and finally whether the observing dates are viable for the requested ORIENT angle.
6.5.2 Determining a binary’s orbital elements using FGS1r in Trans mode
Goal: Observe a known faint (V=16) close (separation ~40 mas) binary in Trans mode in order to determine the system’s relative orbit from which the orbital element, and hence, the system’s mass can be derived.
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Figure 6.2 illustrates the geometry of the binary with respect to the POS TARG and detector reference frames.
Figure 6.2: Example 2: Field of View at Special Orientation
Visit_Number: 1
Visit_Requirements: ORIENT 46.6D TO 48.6D
Visit_Comments: Two Guide Star FineLock Required. Please notify Contact Scientist if two guide stars cannot be found.
Exposure_Number: 01
Target_Name: Close_Binary
Config: FGS
Opmode: TRANS
Aperture: 1
Sp_Element: F583W
Optional_Parameters: SCANS=83, STEP-SIZE=0.6
Time_Per_Exposure: 1729S
Special_Requirements:
Comment:
Visit_Number: 2
Visit_Requirements: AFTER 1 BY 30D TO 32D
ORIENT -24D TO -25D FROM NOMINAL
Visit_Comments: Two Guide Star FineLock Required.
Exposure_Number: 01
Target_Name: Close_Binary
Config: FGS
Opmode: TRANS
Aperture: 1
Sp_Element: F583W
Optional_Parameters: SCANS=83, STEP-SIZE=0.6
Number_of_Iterations: 1
Time_Per_Exposure: 1729S
Special_Requirements:
 
And similar Visits for 3 and 4.
 
Running the proposal template file through APT will inform the observer whether the syntax is correct, whether the exposures fit in an orbit and how much time is left if they do not; and finally, whether the observing dates are viable for the requested ORIENT angle.
6.5.3 Mass determination: Trans and Pos mode
Goal: A bright (V=13), wide binary system (separation = 0.4") is to be observed with FGS1r. Pos mode observations of the binary and neighboring reference stars will be used to determine the binary’s parallax, proper motion, and barycenter. Trans mode observations will be used to establish the system’s relative orbit so that its orbital elements can be derived. Combining these data from several epochs will allow for a dynamical mass determination of the system’s components.
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Texposure = 0.025 * [ScanLength/StepSize] * Nscans
where in this example ScanLength = 1.6 arcsec, StepSize = 0.0006 arcsec, and the number of scans Nscans = 25
 
Figure 6.3 illustrates the geometry of the target and reference stars, while Table 6.9 and Table 6.10 summarize the details of the exposures in the visit.
Figure 6.3: Example 3: Trans + Pos Mode Visits
Wide_Binary1
σSx = 0.008
BL-1-REF2
1
The primary target needs only be listed once in the fixed target list.
2
The “REF” appendix is not required. Rather its use is suggest simply for book keeping purposes.

Table 6.10: Reference/Check Star Pattern
6.5.4 Faint binary with Trans mode: special background measurements
Goal: A faint (V=15) object suspected to be a close (sep < 30 mas) binary is embedded in nebulosity which contributes about 20% of the light in the vicinity of the target. The putative binary is to be observed in Trans mode. Special additional observations are needed accurately measure the background. To do so, the RA,Dec of two points on the sky about 1 arcmin from the target and to either side of it are specified as “targets” in the proposal. These “targets” are to be observed in Pos mode after the Trans mode observation of the faint science target (the FGS high voltage, which enable the PMTs to count photons, does not get turned on until after the IFOV is placed at the expected location of the first target to be observed in the visit. The background data is to be acquired as the IFOV slews away from the science object to the reference “targets”. During this time the PMTs record the background counts.)
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Figure 6.4 illustrates a possible geometry of the field, while Table 6.11 summarizes the total exposure times for the target and reference star, and dark sky observations.
Figure 6.4: Example 4: Trans + Pos Mode Exposures
Table 6.11: Target and Exposure Input for Example 4
Specify the background targets to be bright (V=8) to minimize target acquisition overheads. Note: these targets will fail to be acquired in FineLock since no coherent source is present. However, the desired photometry will be recorded.
Visit_Number: 1
Visit_Requirements:
Visit_Comments:
 
Exposure_Number: 01
Target_Name: HDFAINT
Config: FGS
Opmode: TRANS
Aperture: 1
Sp_Element: F583W
Optional_Parameters: SCANS=69, STEP-SIZE=0.6
Time_Per_Exposure: 1380S
Special_Requirements: POS TARG = 0,0 SEQ 1-3 NON-INT
 
Exposure_Number: 02
Target_Name: DARK_SKY1
Config: FGS
Opmode: POS
Aperture: 1
Sp_Element: F583W
Optional_Parameters:
Time_Per_Exposure: 60 S
Special_Requirements: SAME POS AS 1
 
Exposure_Number: 03
Target_Name: DARK_SKY2
Config: FGS
Opmode: POS
Aperture: 1
Sp_Element: F583W
Optional_Parameters:
Time_Per_Exposure: 60 S
Special_Requirements: SAME POS AS 01
 

Fine Guidance Sensor Instrument Handbook for Cycle 22 > Chapter 6: Writing a Phase II Proposal > 6.5 Proposal Logsheet Examples

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