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FGS Transfer Mode Reference Targets

FGS Transfer Mode Reference Targets

The following tables describe the reference transfer functions for FGS 3 and FGS 1R, available here in polynomial representations. Table 1 lists the targets, their V magnitudes, B-V color indices, and references where appropriate for all targets for which reference Transfer Functions are available. Table 2a and Table 2b specify the actual reference Transfer Functions for FGS 3 and FGS 1R respectively.

We note that the filters available for astrometry with FGS 3 are listed in Table 5.6 of the FGS Instrument Handbook.

Further details about Transfer Mode observing and calibration can be found in Chapter 5 of the FGS Instrument Handbook.

Table 1. Reference Transfer Function Targets

Target V B-V RA (J2000.0) DEC(J2000.0)
LatCol 1A 9.70 1.92 5h 59m 29.09s +22o 34' 50.23"
HD 28484 7.90 1.70 4h 30m 05.11s +16o 10' 17.10"
SAO 185689 9.30 1.50 17h 45m 06.86s -29o 08' 36.90"
HD 59149 6.70 1.28 7h 29m 30.65s +19o 38' 00.00"
HD 233877 9.70 1.10 11h 52m 54.06s +49o 23' 46.10"
Upgren 69* 9.60 0.50 0h 42m 41.94s +85o 14' 14.08"
LatCol 1B 9.60 0.18 5h 59m 27.33s +22o 34' 39.72"
HD 65896 9.18 0.12 7h 57m 31.82s -60o 37' 51.73"
HD 176425 6.23 0.00 19h 02m 08.30s -41o 54' 36.50"
HD 28149 5.50 -0.00 4h 27m 17.41s +22o 59' 47.50"
HD 68657 5.82 -0.15 8h 11m 11.10s -48o 27' 43.00"
HD 34816 4.30 -0.26 5h 19m 34.46s -13o 10' 36.38"
HD 38666 5.17 -0.28 5h 44m 08.32s -32o 19' 27.47"
*Upgren 69 reference: Upgren, Mesrobian, and Kerridge (1972), AJ, 77, 74.

In the reduction of their data, observers should use that reference Transfer Function (see Table 2) which is closest in time to their observed data, using the same filter on a target of similar color index and close in the field of view to their observation.

In Table 2, the rootname of the reference Transfer Function is given in Column 6. The actual reference files have names of the form ROOTx.poly and ROOTy.poly; and ROOTx.FIT and ROOTy.FIT. The POLY files contain the polynomial representations for the data, and the FIT files contain the polynomial fits evaluated at 1 milli-arcsecond bins. All the files are in ASCII format.

Column 1 gives the date the reference data was observed. The secondary mirror was moved in 1993 on Day 352 (1993.352) in conjunction with the First HST Servicing Mission. Consequently, data taken before 1993.352 should NOT make use reference data after that date. Similarly, data taken after 1993.352 should NOT make use of reference data taken before that date.

Table 2a. FGS 3 Reference Transfer Functions for Pickle Center

Filter: F583W
Date Target V B-V Program Dataset ID
1999 101 LatCol 1A 9.3 1.92 7681 F43P0702M
1998 002 LatCol 1A 9.3 1.92 7681 F43P0202M
1996 291 LatCol 1A 9.3 1.92 6923 F3H50102M
1995 249 LatCol 1A 9.3 1.92 6180 F2VU0102M
1998 225 SAO 185689 9.3 1.50 7681 F43P0602M
1997 220 SAO 185689 9.3 1.50 7681 F43P0102M
1996 293 SAO 185689 9.3 1.50 6923 F3H50202M
1995 249 SAO 185689 9.3 1.50 6180 F2VU0302M
1998 004 HD 233877 9.7 1.1 7681 F43P0502M
1999 121 Upgren 69 9.6 0.5 7598 F44V0802M
1999 017 Upgren 69 9.6 0.5 7598 F44V0701M
1998 184 Upgren 69 9.6 0.5 7598 F44V0602M
1998 141 Upgren 69 9.6 0.5 7598 F44V0502M
1998 034 Upgren 69 9.6 0.5 7609 F4H10101M
1998 001 Upgren 69 9.6 0.5 7598 F44V0402M
1997 262 Upgren 69 9.6 0.5 7598 F44V0301M
1997 217 Upgren 69 9.6 0.5 7598 F44V0201M
1997 205 Upgren 69 9.6 0.5 7598 F44V0101M
1997 090 Upgren 69 9.6 0.5 6919 F3H85502M
1997 024 Upgren 69 9.6 0.5 6919 F3H80502M
1996 297 Upgren 69 9.6 0.5 6919 F3H80202M
1995 255 Upgren 69 9.6 0.5 6175 F2VC0202M
1994 163 Upgren 69 9.6 0.5 4724 F2CS0504M
1994 011 Upgren 69 9.6 0.5 4892 F1IT2501M
1993 134 Upgren 69 9.6 0.5 4892 F1AM0402M
1990 323 Upgren 69 9.6 0.5 3089 F0EJ0501M
1996 009 LatCol 1B 9.6 0.18 6180 F2VU0402M
1996 007 LatCol 1B 9.6 0.18 6922 F3JP0102M
Filter: F5ND
Date Target V B-V Program Dataset ID
1998 003 HD 28484 7.9 1.7 7681 F43P0301M
1996 293 HD 28484 7.9 1.7 6923 F3H50301M
1995 259 HD 28484 7.9 1.7 6181 F2VM0201M
1998 246 HD 59149 6.7 1.28 7681 F43P0402M
1996 291 HD 59149 6.7 1.28 6923 F3H50401M
1995 258 HD 59149 6.7 1.28 6181 F2VM0101M
1997 090 Upgren 69 9.6 0.5 6919 F3H85503M
1997 024 Upgren 69 9.6 0.5 6919 F3H80503M
1996 297 Upgren 69 9.6 0.5 6919 F3H80301M
1995 255 Upgren 69 9.6 0.5 6175 F2VC0203M
1993 134 Upgren 69 9.6 0.5 4724 F1AM0405M
1997 272 HD 65896 9.18 0.12 7682 F44A0401M
1997 202 HD 176425 0.23 0.0 7682 F44A0301M
1995 260 HD 28149 5.5 -0.1 6181 F2VM0301M
1997 343 HD 68657 5.82 -0.15 7682 F44A0501M
1998 008 HD 34816 4.3 -0.26 7682 F44A0101M
1999 008 HD 38666 5.17 -0.28 7682 F44A0602M
1997 223 HD 38666 5.17 -0.28 7682 F44A0201M
Filter: PUPIL
Date Target V B-V Program Dataset ID
1998 002 LatCol 1A 9.7 1.92 7681 F43P0201M
1996 291 LatCol 1A 9.7 1.92 6923 F3H50101M
1995 249 LatCol 1A 9.7 1.92 6180 F2VU0101M
1998 225 SAO 185689 9.3 1.5 7681 F43P060BM
1997 220 SAO 185689 9.3 1.5 7681 F43P0101M
1996 293 SAO 185689 9.3 1.5 6923 F3H50201M
1995 249 SAO 185689 9.3 1.5 6180 F2VU0301M
1995 089 SAO 185689 9.3 1.5 6151 F2NM0601M
1998 004 HD 233877 9.7 1.1 7681 F43P0501M
1999 017 Upgren 69 9.6 0.5 7609 F44V0702M
1998 034 Upgren 69 9.6 0.5 7609 F4H10102M
1997 262 Upgren 69 9.6 0.5 7598 F44V0302M
1997 205 Upgren 69 9.6 0.5 7598 F44V0102M
1997 090 Upgren 69 9.6 0.5 6919 F3H85501M
1997 024 Upgren 69 9.6 0.5 6919 F3H80501M
1996 297 Upgren 69 9.6 0.5 6919 F3H80201M
1995 255 Upgren 69 9.6 0.5 6175 F2VC0201M
1994 163 Upgren 69 9.6 0.5 5555 F2CS0502M
1993 134 Upgren 69 9.6 0.5 4724 F1AM0408M
1990 323 Upgren 69 9.6 0.5 3089 F0EJ0502M
1997 007 LatCol 1B 9.6 0.18 6922 F2VU0401M
1996 009 LatCol 1B 9.6 0.18 6180 F3JP0101M

Table 2b. FGS 1R Reference Transfer Functions for Pickle Center

Filter: F583W
Date Target V B-V Program Dataset ID
1999 121 Upgren 69 9.6 0.5 7597 F44S0901M
1999 081 Upgren 69 9.6 0.5 7597 F44S0801M
1999 010 Upgren 69 9.6 0.5 7597 F44S0701M
1998 285 Upgren 69 9.6 0.5 7954 F4TC1903M
Filter: F550W
1999 010 Upgren 69 9.6 0.5 7597 F44S0702M
Filter: PUPIL
1998 285 Upgren 69 9.6 0.5 7597 F4TC1901M