/ftp/cats/I/323



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I/323            International Celestial Reference Frame 2, ICRF2    (Ma+, 2009)
The following files can be converted to FITS (extension .fit or fit.gz)
	icrf2.dat
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Query from: http://vizier.cds.unistra.fr/viz-bin/VizieR?-source=I/323
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drwxr-xr-x 317 cats archive 8192 Feb 28 11:16 [Up] drwxr-xr-x 4 cats archive 310 Jan 12 2023 [TAR file] -rw-r--r-- 1 cats archive 459 Dec 19 2022 .message -r--r--r-- 1 cats archive 5367 Jul 14 2013 ReadMe -rw-r--r-- 1 cats archive 971 Jul 14 2013 +footg5.gif -rw-r--r-- 1 cats archive 12839 Jul 14 2013 +footg8.gif -r--r--r-- 1 cats archive 467718 Jun 6 2013 icrf2.dat [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 4871900 Jun 7 2013 tn35.pdf
Beginning of ReadMe : I/323 International Celestial Reference Frame 2, ICRF2 (Ma+, 2009) ================================================================================ The Second Realization of the International Celestial Reference Frame by Very Long Baseline Interferometry. Ma C., Arias F.E., Bianco G., Boboltz D.A., Bolotin S.L., Charlot P., Engelhardt G., Fey A.L., Gaume R.A., Gontier A.-M., Heinkelmann R., Jacobs C.S., Kurdubov S., Lambert S.B., Malkin Z.M., Nothnagel A., Petrov L., Skurikhina E., Sokolova J.R., Souchay J., Sovers O.J., Tesmer V., Titov O.A., Wang G., Zharov C.Barache V.E., Bockmann S., Collioud A., Gipson J.M., Gordon D., Lytvyn S.O., MacMillan D.S., Ojha R., Fey A.L., Gordon D., Jacobs C.S. <IERS Technical Note 35 (2009)> =2009ITN....35....1M ================================================================================ ADC_Keywords: Fundamental catalog ; Positional data; VLBI Abstract: This Technical Note describes the generation by an international team of the second realization of the International Celestial Reference Frame (ICRF2) at radio wavelengths using nearly 30 years of Very Long Baseline Interferometry (VLBI) observations. ICRF2 contains precise positions of 3414 compact radio astronomical sources, more than five times the number as in the first ICRF, hereafter ICRF1. Further, the ICRF2 is found to have a noise floor of only 40muas, some 5-6 times better than ICRF1, and an axis stability of 10muas, nearly twice as stable as ICRF1. Alignment of ICRF2 with the International Celestial Reference System (ICRS) was made using 138 stable sources common to both ICRF2 and ICRF1-Ext2. Future maintenance of ICRF2 will be made using a set of 295 new "defining" sources selected on the basis of positional stability and the lack of extensive intrinsic source structure. The stability of these 295 defining sources, and their more uniform sky distribution eliminates the two largest weaknesses of ICRF1.