Astronomy & Astrophysics

All Tables

Table 1: Observational circumstances: dynamical class (1998 SN165 does not belong to a particular class and is generally indicated as TNO), heliocentric distance (r), geocentric distance ( $\Delta$ ) and phase angle ( $\alpha$ ).
Table 2: Observational conditions of the TNOs and Centaurs spectroscopically investigated. For each object we report the observational date and universal time (UT of the beginning of the exposure), the VLT unit and instrument used, the total exposure time, the airmass (mean of the airmass value at the beginning and at the end of observation), and the observed solar analog stars with their airmass used to remove the solar contribution.
Table 3: Results of the photometric observations: V magnitude, B-V, V-R and V-I colors. We also report the date of the observations and the UT relative to the beginning of the photometric acquisition sequence, corresponding to the R filter. The acquisition sequence, taken just before the spectral observations, was usually in the form R-V-B-I-V; B filter observations were not available for the TNOs 1998 SN165 and 2001 QF298. For 2002 AW197, 2002 GB10, 2002 GO9 and 2002 GZ32 the exposure time was of 60 s in R and V filters, 180 s in B and 120 s in I; for 2003 AZ84: 90 s in R and V filters, 240 s in B and 180 s in I; for 50 000 Quaoar: 30 s in R and V, 90 s in B and 30 s in I; for 1998 SN165 and 2001 QF298: 180 s in R and V, 240 s in I.
Table 4: Reflectance slope and relative errors (evaluated in the 5000-8000 Å wavelength range) for the six obtained spectra (named A-F as explained in the text) of 2000 GN171. We put the slope value of F spectrum inside square bracket as it could be affected by errors in the extinction correction process due to the low airmass value. The slope value of the spectrum obtained by the mean of the six different spectra is also given.
Table 5: Reflectance slope and relative errors for all the Centaurs and TNOs observed spectroscopically in the visible range; the objects perihelion distance (q) and their diameter (derived from radiometric and/or thermal and optical measurements, when available, or estimated assuming an albedo of 0.04 (^a Fernandez et al. 2002; ^b Davies et al. 1993; ^c Jewitt & Kalas 1998; ^d Margot et al. 2002; ^e Thomas et al. 2000)), are also given. References (Ref.) for the spectral slopes are: 1. This work; 2. Lazzarin et al. (2003); 3. Barucci et al. (1999); 4. Binzel (1992); 5. Luu & Jewitt (1998); 6. Luu & Jewitt (1996); 7. Boehnhardt et al. (2001); 8. Marchi et al. (2003); 9. de Bergh et al. (2004); 10. Fitzsimmons et al. (1994); 11. Lazzaro et al. (1997); 12. Boehnhardt et al. (2004).