J/A+A/587/A48 Lowell Photometric Database asteroid models (Durech+, 2016)
Asteroid models from the Lowell photometric database.
Durech J., Hanus J, Oszkiewicz D., Vanco R.
<Astron. Astrophys. 587, A48 (2016)>
=2016A&A...587A..48D 2016A&A...587A..48D (SIMBAD/NED BibCode)
ADC_Keywords: Minor planets ; Models
Keywords: minor planets, asteroids: general - methods: data analysis -
techniques: photometric
Abstract:
Information about shapes and spin states of individual asteroids is
important for the study of the whole asteroid population. For
asteroids from the main belt, most of the shape models available now
have been reconstructed from disk-integrated photometry by the
lightcurve inversion method.
We want to significantly enlarge the current sample (∼350) of
available asteroid models.
We use the lightcurve inversion method to derive new shape models and
spin states of asteroids from the sparse-in-time photometry compiled
in the Lowell Photometric Database. To speed up the time-consuming
process of scanning the period parameter space through the use of
convex shape models, we use the distributed computing project
Asteroids@home, running on the Berkeley Open Infrastructure for
Network Computing (BOINC) platform. This way, the period-search
interval is divided into hundreds of smaller intervals. These
intervals are scanned separately by different volunteers and then
joined together. We also use an alternative, faster, approach when
searching the best-fit period by using a model of triaxial ellipsoid.
By this, we can independently confirm periods found with convex models
and also find rotation periods for some of those asteroids for which
the convex-model approach gives too many solutions.
Description:
List of new asteroid models. For each asteroid, there is one or two
pole directions in the ecliptic coordinates, the sidereal rotation
period, rotation period from LCDB and its quality code (if available),
the minimum and maximum lightcurve amplitude, the number of data
points, and the method which was used to derive the unique rotation
period. The accuracy of the sidereal rotation period is of the order
of the last decimal place given. Asteroids marked with asterisk were
independently confirmed by Hanus et al. (2016A&A...586A.108H 2016A&A...586A.108H).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 85 259 List of new asteroid models derived from the
full period interval 2-100 hours
table2.dat 85 69 List of new asteroid models derived from a
restricted period interval
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Byte-by-byte Description of file: table1.dat table2.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- Number Asteroid number
8- 28 A21 --- Name Asteroid name or designation
30 A1 --- Ast [*] '*' if published by Hanus et al.
(2016A&A...586A.108H 2016A&A...586A.108H)
32- 34 D3.2 deg lambda1 Ecliptic pole longitude (J2000.0) for model 1
36- 38 D3.2 deg beta1 Ecliptic pole latitude (J2000.0) for model 1
40- 42 D3.2 deg lambda2 ? Ecliptic pole longitude (J2000.0) for model 2
44- 46 D3.2 deg beta2 ? Ecliptic pole latitude (J2000.0) for model 2
48- 56 F9.6 h P Sidereal period of rotation
58- 65 F8.5 h PLCDB ? Rotation period in the LCDB
67- 70 F4.2 mag Amin ? Minimum lightcurve amplitude in LCDB
72- 75 F4.2 mag Amax ? Maximum lightcurve amplitude in LCDB
77- 78 A2 --- U Uncertainty code according to LCDB
80- 82 I3 --- N Number of photometric points
84- 85 A2 --- Method Method used for period determination (1)
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Note (1): The method which was used to derive the unique rotation period:
C - convex inversion, E - ellipsoids, CE - both methods gave the same
unique period.
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Acknowledgements:
Josef Durech, durech(at)sirrah.troja.mff.cuni.cz
(End) Josef Durech [Charles Univ. in Prague], Patricia Vannier [CDS] 14-Jan-2016