DATA_SET_DESCRIPTION |
Data Set Overview
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The radiometric observations used for the Tucson Revised Index of
Asteroid Data (TRIAD) compilation consist of broadband radiometry
at 10 microns (the N band) and 20 microns (the Q band).
Observations from 1972 through 1978 have been used. The results
are compiled in Morrison and Zellner (1979). References to the
observation papers for each entry are given in the associated
references file.
The observations have been interpreted with the standard model
described in Morrison and Lebofsky (1979), using the computer code
of Jones and Morrison (1974). Further details of the analysis are
described in Morrison and Lebofsky (1979).
This data set includes radiometric diameters and albedos for 195
asteroids. Each asteroid is assigned a quality code as follows:
Code 1 is assigned to single observations or to data with large
internal uncertainties; these values may not be individually
reliable and should be used with caution. Code 2 is assigned in a
broad range of situations, including at the minimum two
independent measurements on a good photometric night. This code
indicates basically secure, believable results. Code 3 is
assigned excellent, consistent, multiply-verified data, almost
always at both 10 and 20 microns. Usually observations from
several nights are required to justify Code 3. While it is not
possible to associate a code directly with uncertainties, the
three codes correspond roughly to internal uncertainties in the
diameters of +/- 20%, 10%, and 5% respectively. The possibility
exists of additional errors of up to 10% in the overall diameter
calibration, due to the absolute flux calibration.
This data set description has been adapted from Morrison and
Lebofsky (1979).
References:
Jones, T.J. and D. Morrison, A recalibration of the
radiometric/photometric method of determining asteroid sizes,
Astron. J. 79, 892-895, 1974. [JONES&MORRISON1974]
Morrison, D., and B. Zellner, Polarimetry and radiometry of the
asteroids, in Asteroids, edited by T. Gehrels, pp. 1090-1097,
University of Arizona Press, Tucson, 1979. [MORRISON&ZELLNER1979]
Morrison, D. and L. Lebofsky, Radiometry of Asteroids, in
Asteroids, T. Gehrels, Ed. (University of Arizona Press, Tucson),
pp. 184-205, 1979. [MORRISON&LEBOFSKY1979]
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