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Table 1

ICRF2 sources that were observed with WFI and SOI: physical characteristics and astrometric results.

Struc. Ind. (Optical − VLBI) Internal 3σ level
IERS ID X S Def.? gof V Type z J − Ks Imager Δα ∗  Δδ σα ∗  σδ σα ∗  σδ

0138−097 2 1 Y 17.5 B 0.733 1.547 WFI  + 024  −042 9 18 72 86
0235+164 2 1 N 3.6 19.0 Q 0.940 2.084 WFI  + 065  −015 16 19 82 88
0237−233 4 2 N 2.8 16.6 Q 2.225 1.480 WFI  + 062  −079 14 12 79 76
0405−123 3 2 N 15.3 Q 0.574 1.183 WFI  + 006  −042 21 19 92 88
0430+052 4 3 N 16.4 14.2 G 0.033 2.089 WFI  −117  −064 6 27 69 105
0440−003 4 1 N 3.8 17.0 Q 0.844 1.722 SOI  −058  −133 4 8 68 71
0506−612 Y 16.9 Q 1.093 1.402 WFI  −032  −065 15 19 81 88
0743−673 N 16.4 Q 1.510 0.770 WFI  + 055  + 018 18 27 86 105
0743−673 N 16.4 Q 1.510 0.770 SOI  + 012  −012 7 5 70 69
0754+100 2 1 N 15.7 B 0.266 1.653 WFI  −040  + 048 17 23 84 96
0754+100 2 1 N 15.7 B 0.266 1.653 SOI  −086  + 070 2 5 67 69
0808+019 1 1 Y 0.6 17.5 B 1.148 1.670 SOI  −041  + 040 4 4 68 68
0829+046 2 2 N 16.7 B 0.174 1.661 SOI  −028  + 027 5 6 69 69
0906+015 3 2 N 1.4 17.8 Q 1.024 1.628 SOI  −029  −050 3 7 68 70
0920−397 2 1 Y 2.7 18.8 Q 0.591 1.756 SOI  −007  + 077 4 3 68 68
1127−145 4 2 N 16.7 Q 1.187 1.682 WFI  −065  + 042 7 13 70 78
1252+119 3 1 Y 4.2 16.2 Q 0.873 1.132 WFI  −032  −073 5 17 69 85
1416+067 3 3 N 16.8 Q 1.437 0.942 WFI  −028  −003 5 5 69 69
1445−161 3 2 N 18.9 Q 2.417 WFI  −050  −044 25 25 101 101
1622−297 3 2 N 7.0 20.5 Q 0.815 1.829 WFI  −039  + 051 23 20 96 90
1936−155 1 1 Y 1.8 19.4 Q 1.657 2.261 WFI  + 029  + 004 28 24 107 98
1937−101 3 1 N 2.7 19.0 Q 3.787 1.461 WFI  + 018  −053 9 8 72 71
2000−330 4 2 N 8.5 19.0 Q 3.783 0.917 WFI  −045  −028 8 9 71 72
2344+092 3 2 N 16.0 Q 0.677 1.100 WFI  −011  + 033 18 23 86 96

Notes. All angular values are in mas. The structure indices were selected by considering that the dates of the VLBI experiments should be closest to those of the respective optical observations presented here (see also Tables 2 and 3). Column 1: source identification; Cols. 2 and 3: X- and S-band structure indices, respectively, as obtained from the BVID; Col. 4: object category (defining – Y (yes) or not defining – N (no)) indicating the object’s presence in the ICRF2 defining source list (http://hpiers.obspm.fr/icrs-pc/); Col. 5: goodness of fit (gof) as given by Gontier et al. (2001); Col. 6: V magnitude; Col. 7: object type – BL Lac (B), quasar (Q), and galaxy (G); Col. 8: redshift; Col. 9: near-infrared colour index J − Ks as obtained from the 2MASS; Col. 10: imager name; Cols. 11 and 12 give the differences in the sense observed minus ICRF2 positions, to the sources whose IDs are listed in Col. 1; Cols. 13 and 14 give the values of σI, as described in Sect. 4, to the sources whose IDs are listed in Col. 1; Cols. 15 and 16 give the value of 3σ, as described in Sect. 4, to the sources whose IDs are listed in Col. 1. The notation α ∗  indicates multiplication by cosδ. Magnitudes, object type, and redshifts were mostly taken from the “Information on radiosources” link at http address given above. The SIMBAD was queried in case of missing information on the redshifts. The concerned sources are: 0237 − 233, 1127 − 145, 1445 − 161, 2000 − 330, 2344 + 092. Regarding the magnitude, it should be noticed that these objects are variable.

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