UKIRT Faint Standards tramsformed to the (new) Mauna Kea Observatory (MKO-NIR) system
Both UKIRT cameras (UFTI and IRCAM) are now equipped with filters from the Mauna Kea Consortium (MKO-NIR) filter set (see the papers “The Mauna Kea Observatories Near-Infrared Filter Set. I. Defining Optimal 1-5 Micron Bandpasses” by Simons & Tokunaga 2002 PASP 114, 169 and “The Mauna Kea Observatories Near-Infrared Filter Set. II. Specifications for a New JHKL’M’ Filter Set for Infrared Astronomy” by Tokunaga et al. 2002 PASP, 114, 180). These filters have been designed to be a better match to the atmospheric windows, offering maximum sensitivity together with minimum dependance on altitude and atmospheric water-vapour content, and are also of excellent optical quality.
The MKO-NIR filter set has been in UFTI since commissioning in October 1998, replaced the old JHK set in IRCAM/TUFTI prior to commissioning of its new plate scale in September 1999, and were installed in UIST prior to its 2002 commissioning. Both the J and H filters are significantly different from the old filters and hence the magnitudes for the Faint Standards on the old IRCAM3 system are no longer on the natural systems of the imagers. Colour transformations have been derived in two ways: one empirically based on UFTI photometry and the other calculated by convolving the known filter profiles with spectroscopic data for a representative set of red stars. The two determinations agree reasonably well but the actual measurements should be used in preference to the transformed values given below. Note that the transformations for IRCAM/TUFTI with the same filter set should be effectively identical.
The transformations between the old IRCAM3 system and the new MKO-NIR system at H and K are well behaved and single-valued. However for the J filter different terms have to be applied depending whether or not the standard star has intrinsic water absorption features. This is due to the fact that the new J filter cuts off shorter than the old filter, specifically to avoid water absorption in the terrestrial atmosphere. We have determined that for stars with no intrinsic water features the colour transformations are:
K(old) = K(new) + 0.020[+/-0.005](J-K)(new) (J-H)(old) = 1.040[+/-0.010](J-H)(new) (H-K)(old) = 0.830[+/-0.010](H-K)(new) (J-K)(old) = 0.960[+/-0.010](J-K)(new) K(new) = K(old) - 0.020[+/-0.005](J-K)(old) (J-H)(new) = 0.960[+/-0.010](J-H)(old) (H-K)(new) = 1.205[+/-0.010](H-K)(old) (J-K)(new) = 1.040[+/-0.010](J-K)(old)
however for stars with significant water absorption, stars with spectral type M4 through to the L class (but not including the T class with methane absorption, see Stephens & Leggett 2004 PASP 116, 9):
K(new) = K(old) - 0.020[+/-0.005](J-K)(old) (J-H)(new) = 0.870[+/-0.010](J-H)(old) (H-K)(new) = 1.205[+/-0.010](H-K)(old) (J-K)(new) = 0.980[+/-0.010](J-K)(old)
We have applied the appropriate transformations to the UKIRT Faint Standards and the Table below lists the combined fundamental and extended standards list with the photometry given in the cameras’ current natural system, which is defined by the Mauna Kea consortium JHK filters. The errors include both observational error and system transformation uncertainty.
For more information on e.g. selection of standard stars see the following sections on either the original Fundamental List of UKIRT standards or the later Extended List.
Number Other RA (J2000) Dec K sem N J-H sem N H-K sem N Invis
Name on TV?
FS 1 G158-100 00 33 54.48 -12 07 58.1 12.955 (0.005) [09] 0.372 (0.005) [10] 0.069 (0.004) [09]
FS 2 SA92-342 00 55 09.93 +00 43 13.1 10.467 (0.004) [12] 0.198 (0.004) [11] 0.042 (0.002) [12]
FS 3 F11 01 04 21.63 +04 13 36.0 12.827 (0.003) [07] -0.107 (0.003) [07] -0.107 (0.005) [08]
FS 4 SA93-317 01 54 37.70 +00 43 00.5 10.279 (0.002) [11] 0.229 (0.005) [11] 0.039 (0.002) [11]
FS 5 F16 01 54 34.65 -06 46 00.4 12.339 (0.005) [08] 0.004 (0.002) [07] -0.006 (0.002) [08]
FS 6 F22 02 30 16.64 +05 15 51.1 13.385 (0.005) [08] -0.057 (0.005) [08] -0.083 (0.005) [08]
FS 7 SA94-242 02 57 21.21 +00 18 38.2 10.942 (0.002) [14] 0.121 (0.002) [14] 0.039 (0.001) [14]
FS 10 GD50 03 48 50.20 -00 58 31.2 14.987 (0.011) [09] -0.100 (0.006) [09] -0.142 (0.010) [09]
FS 11 SA96-83 04 52 58.92 -00 14 41.6 11.252 (0.002) [18] 0.062 (0.001) [18] 0.027 (0.001) [18]
FS 12 GD71 05 52 27.66 +15 53 14.3 13.920 (0.006) [13] -0.110 (0.003) [13] -0.113 (0.005) [13]
FS 13 SA97-249 05 57 07.59 +00 01 11.4 10.133 (0.003) [12] 0.300 (0.004) [13] 0.058 (0.001) [12]
FS 14 Rubin149 07 24 14.40 -00 33 04.1 14.200 (0.008) [08] -0.062 (0.007) [08] -0.037 (0.010) [08]
FS 15 M67-I-48 08 51 05.81 +11 43 46.9 12.340 (0.004) [13] 0.324 (0.005) [13] 0.065 (0.002) [13]
FS 16 M67-IV-8 08 51 15.01 +11 49 21.2 12.621 (0.004) [11] 0.278 (0.004) [11] 0.049 (0.002) [11]
FS 17 M67-IV-27 08 51 19.31 +11 52 10.4 12.266 (0.003) [10] 0.314 (0.004) [10] 0.067 (0.002) [10]
FS 18 SA100-280 08 53 35.51 -00 36 41.7 10.521 (0.002) [11] 0.242 (0.004) [11] 0.049 (0.002) [11]
FS 19 G162-66 10 33 42.75 -11 41 38.3 13.786 (0.006) [09] -0.082 (0.005) [09] -0.139 (0.007) [09]
FS 20 G163-50 11 07 59.93 -05 09 26.1 13.503 (0.010) [06] -0.036 (0.006) [06] -0.078 (0.008) [06]
FS 21 GD140 11 37 05.15 +29 47 58.4 13.150 (0.002) [09] -0.066 (0.004) [09] -0.108 (0.004) [09]
FS 33 GD153 12 57 02.30 +22 01 52.8 14.258 (0.005) [06] -0.108 (0.002) [05] -0.124 (0.008) [05]
FS 23 M3-193 13 41 43.57 +28 29 49.5 12.363 (0.004) [11] 0.506 (0.006) [11] 0.080 (0.003) [11]
FS 27 M13-A14 16 40 41.56 +36 21 12.4 13.121 (0.005) [10] 0.294 (0.006) [10] 0.058 (0.004) [10]
FS 35 anon 18 27 13.52 +04 03 09.4 11.739 (0.005) [14] 0.354 (0.005) [15] 0.101 (0.002) [15]
FS 34 EG141 20 42 34.73 -20 04 34.8 13.003 (0.004) [09] -0.074 (0.003) [09] -0.089 (0.005) [09]
FS 29 G93-48 21 52 25.36 +02 23 20.7 13.314 (0.003) [11] -0.065 (0.002) [11] -0.084 (0.003) [11]
FS 30 SA114-750 22 41 44.72 +01 12 36.5 12.023 (0.003) [15] -0.040 (0.002) [13] -0.037 (0.002) [14]
FS 31 GD246 23 12 21.60 +10 47 04.1 14.042 (0.007) [10] -0.125 (0.005) [10] -0.119 (0.005) [10]
FS 32 F108 23 16 12.37 -01 50 34.6 13.680 (0.007) [08] -0.103 (0.003) [08] -0.104 (0.005) [08]
FS 101 fs2-29 00 13 43.58 +30 37 59.9 10.381 (0.006) [08] 0.133 (0.004) [08] 0.039 (0.003) [08]
FS 102 p525-e 00 24 28.50 +07 49 00.1 11.211 (0.005) [06] 0.305 (0.006) [07] 0.063 (0.002) [06]
FS 103 p241-g 00 36 29.60 +37 42 54.3 11.719 (0.007) [06] 0.494 (0.006) [06] 0.101 (0.006) [06]
FS 104 p194-r 01 04 59.43 +41 06 30.8 10.406 (0.005) [07] 0.097 (0.004) [07] 0.031 (0.002) [07]
FS 105 p527-f 01 19 08.19 +07 34 11.5 10.959 (0.005) [06] 0.452 (0.009) [06] 0.096 (0.001) [06]
FS 106 p152-f 01 49 46.94 +48 37 53.2 11.745 (0.006) [05] 0.591 (0.008) [06] 0.124 (0.006) [05]
FS 107 fs2-03 01 54 10.14 +45 50 38.0 10.226 (0.015) [03] 0.204 (0.010) [03] 0.060 (0.004) [03]
FS 108 fs2-04 03 01 09.85 +46 58 47.7 9.724 (0.004) [05] 0.278 (0.005) [05] 0.071 (0.003) [06]
FS 109 g-129 03 13 24.16 +18 49 38.4 10.795 (0.007) [06] 0.445 (0.007) [07] 0.194 (0.004) [07]
FS 110 p533-d 03 41 02.22 +06 56 15.9 11.316 (0.004) [06] 0.296 (0.004) [07] 0.094 (0.004) [07]
FS 111 fs2-05 03 41 08.55 +33 09 35.5 10.282 (0.006) [07] 0.252 (0.007) [07] 0.107 (0.002) [07]
FS 112 s618-d 03 47 40.70 -15 13 14.4 10.893 (0.005) [06] 0.253 (0.005) [06] 0.057 (0.005) [06]
FS 113 p117-f 04 00 14.07 +53 10 38.5 12.422 (0.006) [06] 0.357 (0.005) [06] 0.131 (0.005) [06]
FS 114 Hy214 04 19 41.72 +16 45 22.4 13.426 (0.008) [05] 0.525 (0.006) [06] 0.406 (0.007) [05]
FS 115 b216-b5 04 23 18.17 +26 41 16.4 10.124 (0.012) [06] 1.522 (0.018) [07] 0.930 (0.009) [07] *
FS 116 b216-b7 04 23 50.18 +26 40 07.7 10.914 (0.009) [07] 1.211 (0.014) [06] 0.616 (0.006) [07] *
FS 117 b216-b9 04 23 56.61 +26 36 38.0 10.050 (0.008) [07] 0.912 (0.012) [07] 0.527 (0.005) [07]
FS 118 b216-b13 04 24 33.49 +26 33 37.8 10.426 (0.007) [06] 0.694 (0.009) [06] 0.321 (0.003) [06]
FS 119 fs2-53 05 02 57.44 -01 46 42.6 9.850 (0.004) [06] 0.043 (0.006) [06] 0.023 (0.002) [06]
FS 120 lhs216 06 14 01.44 +15 09 58.3 10.612 (0.007) [06] 0.483 (0.006) [07] 0.240 (0.006) [07]
FS 121 s772-g 06 59 46.82 -04 54 33.2 11.302 (0.004) [07] 0.539 (0.006) [07] 0.130 (0.003) [07]
FS 122 p161-d 07 00 52.02 +48 29 24.0 11.332 (0.003) [07] 0.257 (0.004) [06] 0.055 (0.003) [07]
FS 123 p486-r 08 51 11.88 +11 45 21.5 10.212 (0.004) [10] -0.012 (0.002) [10] -0.027 (0.004) [10]
FS 124 lhs254 08 54 12.07 -08 04 58.9 10.761 (0.005) [06] 0.418 (0.008) [07] 0.321 (0.006) [07]
FS 125 p259-c 09 03 20.60 +34 21 03.9 10.365 (0.005) [10] 0.361 (0.004) [09] 0.063 (0.003) [10]
FS 126 p487-f 09 19 18.73 +10 55 54.2 11.667 (0.006) [10] 0.541 (0.006) [10] 0.127 (0.003) [09]
FS 127 p212-c 10 06 29.03 +41 01 26.6 11.648 (0.004) [10] 0.251 (0.005) [09] 0.048 (0.003) [10]
FS 128 lhs2347 11 05 10.40 +07 06 48.7 12.059 (0.006) [05] 0.536 (0.007) [05] 0.372 (0.006) [06]
FS 129 lhs2397a 11 21 48.95 -13 13 07.9 10.686 (0.008) [08] 0.630 (0.009) [08] 0.512 (0.005) [07]
FS 130 p264-f 11 24 55.92 +34 44 38.5 12.238 (0.005) [06] 0.572 (0.008) [07] 0.119 (0.004) [06]
FS 131 p266-c 12 14 25.40 +35 35 55.6 11.308 (0.005) [05] 0.249 (0.004) [06] 0.039 (0.004) [05]
FS 132 s860-d 12 21 39.36 -00 07 13.3 11.830 (0.004) [06] 0.278 (0.004) [07] 0.041 (0.005) [06]
FS 133 p172-e 13 15 52.80 +46 06 36.9 11.868 (0.005) [05] 0.352 (0.006) [05] 0.072 (0.003) [04]
FS 134 lhs2924 14 28 43.37 +33 10 41.5 10.724 (0.007) [06] 0.649 (0.008) [06] 0.511 (0.005) [06]
FS 135 s867-v 14 40 58.04 -00 27 46.6 11.586 (0.004) [05] 0.330 (0.005) [05] 0.055 (0.002) [06]
FS 136 S868-G 14 59 32.05 -00 06 17.0 11.870 (0.006) [06] 0.531 (0.007) [06] 0.108 (0.004) [06]
FS 137 p565-c 16 26 42.72 +05 52 20.3 11.823 (0.006) [05] 0.262 (0.007) [07] 0.054 (0.003) [06]
FS 138 p275-a 16 28 06.72 +34 58 48.3 10.411 (0.006) [07] 0.029 (0.006) [06] 0.002 (0.002) [07]
FS 139 p137-f 16 33 52.96 +54 28 22.1 12.091 (0.007) [07] 0.492 (0.008) [07] 0.110 (0.003) [07]
FS 140 s587-t 17 13 22.65 -18 53 33.8 10.360 (0.006) [05] 0.354 (0.005) [05] 0.072 (0.005) [05]
FS 141 p389-d 17 48 58.87 +23 17 43.7 10.805 (0.006) [07] 0.291 (0.005) [07] 0.074 (0.003) [07]
FS 142 Ser-EC51 18 29 51.26 +01 13 19.0 13.348 (0.016) [02] 1.435 (0.016) [02] 0.904 (0.010) [02] *
FS 143 Ser-EC68 18 29 53.79 +01 13 29.9 12.947 (0.020) [04] 2.243 (0.026) [03] 1.446 (0.013) [04] *
FS 144 Ser-EC84 18 29 56.90 +01 12 47.1 10.970 (0.019) [02] 2.412 (0.030) [02] 1.569 (0.016) [02] *
FS 145 Ser-EC160 18 30 05.81 +01 13 47.3 12.064 (0.025) [04] 3.105 (0.059) [04] 1.882 (0.018) [04] *
FS 146 p280-u 18 54 04.01 +37 07 18.6 10.129 (0.006) [05] 0.491 (0.007) [05] 0.084 (0.003) [05]
FS 147 p230-a 19 01 55.27 +42 29 19.6 9.865 (0.004) [04] 0.027 (0.004) [05] 0.018 (0.003) [05]
FS 148 s810-b 19 41 23.41 -03 50 56.9 9.477 (0.004) [05] 0.019 (0.008) [05] 0.013 (0.005) [05]
FS 149 p338-c 20 00 39.25 +29 58 40.0 10.086 (0.009) [06] 0.022 (0.008) [06] -0.004 (0.003) [06]
FS 150 fs2-22 20 36 08.44 +49 38 23.5 9.956 (0.005) [08] 0.148 (0.007) [09] 0.053 (0.003) [09]
FS 151 p340-h 21 04 14.75 +30 30 21.2 11.869 (0.007) [08] 0.263 (0.007) [08] 0.074 (0.005) [08]
FS 152 p460-e 22 27 16.12 +19 16 59.2 11.045 (0.006) [09] 0.500 (0.007) [08] 0.075 (0.004) [09]
FS 153 s820-e 23 02 32.07 -03 58 53.1 10.882 (0.005) [06] 0.557 (0.008) [07] 0.127 (0.002) [07]
FS 154 s893-d 23 18 10.08 +00 32 55.6 11.058 (0.005) [06] 0.253 (0.004) [07] 0.051 (0.003) [07]
FS 155 fs2-27 23 49 47.82 +34 13 05.1 9.401 (0.007) [06] 0.491 (0.006) [05] 0.102 (0.003) [06]
NB: (1) FS18 is a double; separation = 1."36, p.a. 96 degrees, Delta(K) = 2.2
(2) Stars which are too faint in the visible to be readily seen on an acquisition TV are marked with
an asterisk (*) in the last column.