J/A+A/625/A139 Thermal properties of slow asteroids (Marciniak+, 2019)
Thermal properties of slowly rotating asteroids: results from targeted survey.
Marciniak A., Ali-Lagoa V, Mueller T.G., Szakats R., Molnar L., Pal A.,
Podlewska-Gaca E., Parley N., Antonini P., Barbotin E., Behrend R.,
Bernasconi L., Butkiewicz-Bak M., Crippa R., Duffard R., Ditteon R.,
Feuerbach M., Fauvaud S., Garlitz J., Geier S., Goncalves R., Grice J.,
Grzeskowiak I., Hirsch R., Horbowicz J., KamiNski K., KamiNska M.K.,
Kim D.-H., Kim M.-J., Konstanciak I., Kudak V., Kulczak P., Maestre J.L.,
Manzini F., Marks S., Monteiro F., Ogloza W., Oszkiewicz D., Pilcher F.,
Perig V., Polakis T., PoliNska M., Roy R., Sanabria J.J., Santana-Ros T.,
Skiff B., Skrzypek J., Sobkowiak K., Sonbas E., Thizy O., Trela P.,
Urakawa S., Zejmo M., Zukowski K.
<Astron. Astrophys. 625, A139 (2019)>
=2019A&A...625A.139M 2019A&A...625A.139M (SIMBAD/NED BibCode)
ADC_Keywords: Solar system ; Minor planets
Keywords: minor planets: asteroids - techniques: photometric -
radiation mechanisms: thermal
Abstract:
Earlier work suggests that slowly rotating asteroids should have
higher thermal inertias than faster rotators because the heat wave
penetrates deeper into the subsurface. However, thermal inertias have
been determined mainly for fast rotators due to selection effects in
the available photometry used to obtain shape models required for
thermophysical modelling (TPM).
Our aims are to mitigate these selection effects by producing shape
models of slow rotators, to scale them and compute their thermal
inertia with TPM, and to verify whether thermal inertia increases with
the rotation period.
To decrease the bias against slow rotators, we conducted a photometric
observing campaign of main-belt asteroids with periods longer than
12h, from multiple stations worldwide, adding in some cases data from
WISE and Kepler space telescopes. For spin and shape reconstruction we
used the lightcurve inversion method, and to derive thermal inertias
we applied a thermophysical model to fit available infrared data from
IRAS, AKARI, and WISE.
We present new models of 11 slow rotators that provide a good fit to
the thermal data. In two cases, the TPM analysis showed a clear
preference for one of the two possible mirror solutions. We derived
the diameters and albedos of our targets in addition to their thermal
inertias, which ranged between 3-3+33 and
45-30+60J/m2/s1/2/K.
Together with our previous work, we have analysed 16 slow rotators
from our dense survey with sizes between 30 and 150 km. The current
sample thermal inertias vary widely, which does not confirm the
earlier suggestion that slower rotators have higher thermal inertias.
Description:
The files contain asteroid brightness and geometry for corresponding
epochs. The "*lcs.dat" files were used for obtaining shape models and
spin states of the asteroids using multi-apparition data. Individual
lightcurves within a file are separated by an empty line, all
lightcurves are relative.
The files "*obs.dat" contain information on the observing
circumstances, observers, and sites of each of the the new lightcurves
published within this paper. Individual apparitions are spaced by an
empty line.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
100lcs.dat 112 3479 Asteroid 100 Hekate individual lightcurves
109lcs.dat 112 1570 Asteroid 109 Felicitas individual lightcurves
195lcs.dat 112 1855 Asteroid 195 Eurykleia individual lightcurves
301lcs.dat 112 1786 Asteroid 301 Bavaria individual lightcurves
335lcs.dat 112 2097 Asteroid 335 Roberta individual lightcurves
380lcs.dat 112 1219 Asteroid 380 Fiducia individual lightcurves
468lcs.dat 112 1091 Asteroid 468 Lina individual lightcurves
538lcs.dat 112 2927 Asteroid 538 Friederike individual lightcurves
653lcs.dat 112 1387 Asteroid 653 Berenike individual lightcurves
673lcs.dat 112 1470 Asteroid 673 Edda individual lightcurves
834lcs.dat 112 901 Asteroid 834 Burnhamia individual lightcurves
100obs.dat 91 48 Observing circumstances of asteroid 100 Hekate
109obs.dat 89 52 Observing circumstances of asteroid 109 Felicitas
195obs.dat 89 52 Observing circumstances of asteroid 195 Eurykleia
301obs.dat 91 25 Observing circumstances of asteroid 301 Bavaria
335obs.dat 88 26 Observing circumstances of asteroid 335 Roberta
380obs.dat 88 37 Observing circumstances of asteroid 380 Fiducia
468obs.dat 91 39 Observing circumstances of asteroid 468 Lina
538obs.dat 91 78 Observing circumstances of asteroid 538 Friederike
653obs.dat 91 28 Observing circumstances of asteroid 653 Berenike
673obs.dat 88 34 Observing circumstances of asteroid 673 Edda
834obs.dat 88 32 Observing circumstances of asteroid 834 Burnhamia
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Byte-by-byte Description of file: *lcs.dat
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Bytes Format Units Label Explanations
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2- 15 F14.6 d JD JD epoch corrected for the light-time
corresponding to the Earth-asteroid distance
17- 28 E12.6 --- br Relative brightness in intensity units,
mean brightness of each lightcurve is unity
30- 42 E13.6 AU Sx x component of the vector from the asteroid to
the Sun in J2000 ecliptic Cartesian coordinates
44- 56 E13.6 AU Sy y component of the vector from the asteroid to
the Sun in J2000 ecliptic Cartesian coordinates
58- 70 E13.6 AU Sz z component of the vector from the asteroid to
the Sun in J2000 ecliptic Cartesian coordinates
72- 84 E13.6 AU Ex x component of the vector from the asteroid to
the Earth in J2000 ecliptic Cartesian coordinates
86- 98 E13.6 AU Ey y component of the vector from the asteroid to
the Earth in J2000 ecliptic Cartesian coordinates
100-112 E13.6 AU Ez z component of the vector from the asteroid to
the Earth in J2000 ecliptic Cartesian coordinates
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Byte-by-byte Description of file: *obs.dat
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Bytes Format Units Label Explanations
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2- 14 A13 "datime" Obs.date Particular observing run observation date
(YYYY/MMM/DD.d)
18- 22 F5.1 deg Lambda Ecliptic longitude of the target
26- 29 F4.1 deg Phase Phase angle (Sun-Target-Observer)
32- 35 F4.1 h Dur Duration of the observing run
39- 43 F5.3 mag Sigma ? Photometric scatter
47- 67 A21 --- Observ Observer(s)
70- 91 A22 --- Site Observing site
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Acknowledgements:
Anna Marciniak, am(at)amu.edu.pl
(End) Patricia Vannier [CDS] 24-Apr-2019