J/A+A/657/A80 Asteroids phase curves using SLOAN MOC (Alvarez-Candal+, 2022)
Phase curves of small bodies from the SLOAN Moving Objects Catalog.
Alvarez-Candal, A. Benavidez, P. Campo Bagatin A., Santana-Ros T.
<Astron. Astrophys. 657, A80 (2022)>
=2022A&A...657A..80A 2022A&A...657A..80A (SIMBAD/NED BibCode)
ADC_Keywords: Minor planets ; Colors ; Magnitudes, absolute ; Photometry, ugriz
Keywords: methods: data analysis - catalogs - minor planets, asteroids: general
Abstract:
Large photometric surveys are producing, and will continue doing it,
massive amounts of data on small bodies. Usually,these data will be
sparsely obtained at arbitrary (and unknown) rotational phases.
Therefore, new methods to process such data need to be developed to
make the most of those large catalogs.
We aim to produce a method to create phase curves of small bodies
considering the uncertainties introduced not only by the nominal
errors in the magnitudes, but also the effect introduced by rotational
variations.We use as a benchmark the data from the SLOAN Moving
Objects Catalog with the objective to construct phase curves of all
small bodies in there, in the u, g, r, i, and z, filters. We will
obtain from the phase curves the absolute magnitudes and set up with
them the absolute colors, which are the colors of the asteroids not
affected by changes in phase angle.
We select objects with >3 observations taken in, at least, one filter
and spanned over a minimum of 5 degrees in phase angle. We developed a
method that combines Monte Carlo simulations and Bayesian inference to
estimate the absolute magnitudes using the HG12 photometric system.
We obtained almost 15000 phase curves, about 12000 including all
five filters. The absolute magnitudes and absolute colors are
compatible with previously published data, supporting our
method.Conclusions. The method we developed is fully automatic and
well suited to be run on large amounts of data. Moreover, it
includes the nominal uncertainties in the magnitudes and the whole
distribution of possible rotational states of the objects producing,
possibly,less precise values, i.e., larger uncertainties, but more
accurate, i.e., closer to the real value. To the best of our
knowledge, this work is the first to include the effect of rotational
variations in such a way.
Description:
Phase curves parameters for about 14k minor bodies in the ugriz
systems plus Jhonson's V (obtained from transforming g and r
magnitudes). For each objects are given the absolute magnitudes and
phase coefficients, their respective uncertainties, and the minimum
phase angle and total span in phase angle.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 660 14801 Absolute magnitudes and phase coefficients
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 20 A20 --- Object Designation of the minor body
21- 31 F11.5 --- Hu ?=-9999 Absolute magnitude in the u filter
38- 48 F11.5 --- e_Hu ?=-9999 Lower uncertainty in Hu
55- 65 F11.5 --- E_Hu ?=-9999 Upper uncertainty in Hu
67- 68 I2 --- Nu Number of observation in the u filter
74- 84 F11.5 --- Hg ?=-9999 Absolute magnitude in the g filter
91-101 F11.5 --- e_Hg ?=-9999 Lower uncertainty in Hg
108-118 F11.5 --- E_Hg ?=-9999 Upper uncertainty in Hg
120-121 I2 --- Ng Number of observation in the g filter
127-137 F11.5 --- Hr ?=-9999 Absolute magnitude in the r filter
144-154 F11.5 --- e_Hr ?=-9999 Lower uncertainty in Hr
161-171 F11.5 --- E_Hr ?=-9999 Upper uncertainty in Hr
173-174 I2 --- Nr Number of observation in the r filter
180-190 F11.5 --- Hi ?=-9999 Absolute magnitude in the i filter
197-207 F11.5 --- e_Hi ?=-9999 Lower uncertainty in Hi
214-224 F11.5 --- E_Hi ?=-9999 Upper uncertainty in Hi
226-227 I2 --- Ni Number of observation in the i filter
233-243 F11.5 --- Hz ?=-9999 Absolute magnitude in the z filter
250-260 F11.5 --- e_Hz ?=-9999 Lower uncertainty in Hz
267-277 F11.5 --- E_Hz ?=-9999 Upper uncertainty in Hz
279-280 I2 --- Nz Number of observation in the z filter
286-296 F11.5 --- HV ?=-9999 Absolute magnitude in the V filter
303-313 F11.5 --- e_HV ?=-9999 Lower uncertainty in HV
320-330 F11.5 --- E_HV ?=-9999 Upper uncertainty in HV
332-333 I2 --- NV Number of observation in the V filter
341-351 F11.5 --- Gu ?=-9999 Phase coefficient in the u filter
358-368 F11.5 --- e_Gu ?=-9999 Lower uncertainty in Gu
375-385 F11.5 --- E_Gu ?=-9999 Upper uncertainty in Gu
393-403 F11.5 --- Gg ?=-9999 Phase coefficient in the g filter
410-420 F11.5 --- e_Gg ?=-9999 Lower uncertainty in Gg
427-437 F11.5 --- E_Gg ?=-9999 Upper uncertainty in Gg
445-455 F11.5 --- Gr ?=-9999 Phase coefficient in the r filter
462-472 F11.5 --- e_Gr ?=-9999 Lower uncertainty in Gr
479-489 F11.5 --- E_Gr ?=-9999 Upper uncertainty in Gr
497-507 F11.5 --- Gi ?=-9999 Phase coefficient in the i filter
514-524 F11.5 --- e_Gi ?=-9999 Lower uncertainty in Gi
531-541 F11.5 --- E_Gi ?=-9999 Upper uncertainty in Gi
549-559 F11.5 --- Gz ?=-9999 Phase coefficient in the z filter
566-576 F11.5 --- e_Gz ?=-9999 Lower uncertainty in Gz
583-593 F11.5 --- E_Gz ?=-9999 Upper uncertainty in Gz
601-611 F11.5 --- GV ?=-9999 Phase coefficient in the V filter
618-628 F11.5 --- e_GV ?=-9999 Lower uncertainty in GV
635-645 F11.5 --- E_GV ?=-9999 Upper uncertainty in GV
647-651 F5.2 deg am Minimum phase angle
656-660 F5.2 deg Da Range of phase angle covered
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Acknowledgements:
Alvaro Alvarez-Candal, varobes(at)gmail.com
(End) Alvaro Alvarez-Candal [IAA, Spain], Patricia Vannier [CDS] 17-Sep-2021