Filling the gap Asteroids with slow rotation in thermal infrared A. - PowerPoint PPT Presentation

Selection effects Shape models TPM Results Summary Filling the gap Asteroids with slow rotation in thermal infrared A. Marciniak 1 , V. Alí-Lagoa, T. Müller, P . Bartczak R. Behrend, M. Butkiewicz-B ˛ ak, G. Dudzi´ nski, R. Duffard, K. Dziadura, S. Fauvaud, S. Geier, J. Grice, R. Hirsch, J. Horbowicz, K. Kami´ nski, P . Kankiewicz, D.-H. Kim, M.-J. Kim, I. Konstanciak, V. Kudak, L. Molnár, F. Monteiro, W. Ogłoza, D. Oszkiewicz, A. Pál, N. Parley, F. Pilcher, E. Podlewska - Gaca, T. Polakis, J. J. Sanabria, T. Santana-Ros, B. Skiff, K. Sobkowiak, R. Szakáts, S. Urakawa, M. ˙ Zejmo, K. ˙ Zukowski 1. Astronomical Observatory Institute, Faculty of Physics, A. Mickiewicz University, Pozna´ n, Poland.

Selection effects Shape models TPM Results Summary Selection effects in MBA models All 1230 asteroids with H ≥ 11 mag Division values: P = 12 h, a max = 0.25 mag. Marciniak et al. 2018

Selection effects Shape models TPM Results Summary Selection effects in fainter MBA models All 2274 asteroids with 11 < H ≤ 13 mag Division values: P = 12 h, a max = 0.25 mag. Marciniak et al. 2018

Selection effects Shape models TPM Results Summary Selected lightcurves 335 Roberta 109 Felicitas P=12.027 h P = 13.188 h 2013 -4,5 29 Sep, Bor. 2017 18 Oct, Organ M. Jan 22.3 CTIO 19 Oct, Bor. Jan 27.1 Bor. Jan 29.1 Bor. -3,3 19 Oct, Organ M. Feb 16.1 Bor. 25 Oct, Bor. 21 Nov, Organ M. Feb 22.4 Tempe 18 Dec, Organ M. -4,4 Feb 23.4 Tempe Relative C and R magnitude 23 Dec, Bor. Feb 24.4 Tempe Relative C magnitude Feb 25.4 Tempe Feb 27.4 Tempe Mar 1.4 Tempe -3,2 -4,3 -3,1 -4,2 Zero time at 2017 Jan 28.9650 UTC, LT corr. Zero time at: 2013 Sep 28.9158 UTC, LT corr. 0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1 0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1 Phase Phase 100 Hekate 538 Friederike P=27.068 h P=46.74 h 8,35 -3,5 Feb 1.1 Kepler 2018 Feb 2.1 Kepler Feb 3.3 Kepler 8,4 Feb 4.0 Kepler Feb 5.0 Kepler Feb 5.9 Kepler -3,4 May 19.1 Kepler Relative R and C magnitude 8,45 May19.8 Kepler Relative R magnitude May 20.8 Kepler May 21.8 Kepler May 22.5 Kepler 2018 8,5 -3,3 Oct 18.1 Bor. Oct 19.0 Bor. Nov 1.1 Bor. Nov 4.1 OAdM 8,55 Nov 6.1 Bor. Nov 7.1 Bor. Nov 10.4 Organ M. -3,2 Nov 17.4 Organ M. Nov 18.0 Bor. 8,6 Nov 29.3 Organ M. Dec 5.9 Bor. Dec 11.2 OAdM Zero time at: 2018 Jan 31.7150 UTC, LT corr. Zero time at: 2018 Oct 17.9492 UTC, LT corr. Dec 14.3 Organ M. 8,65 -3,1 0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1 0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1 Phase Phase

Selection effects Shape models TPM Results Summary Fitting the shape models to stellar occultation chords Diameters of equivalent volume sphere: CONVEX (2011): 72 ± 4 km; CONVEX (2013): 74 ± 5 km SAGE (2011): 70 ± 4 km; SAGE (2013): 72 ± 3 km Marciniak et al. 2018

Selection effects Shape models TPM Results Summary Thermophysical modelling Insolation and surface temperature distribution: (159) Aemilia

Selection effects Shape models TPM Results Summary O-C plots for (159) Aemilia model applied in TPM

Selection effects Shape models TPM Results Summary Rotation Radiometric solution for combined data. Target period Taxonomic Diameter Albedo Thermal inertia [Jm − 2 s − 0 . 5 K − 1 ] [h] type [km] 159 Aemilia 24 . 4787 Ch 137 0 . 054 50 ± 0 . 0001 ± 8 ± 0 . 015 ± 50 227 Philosophia 26 . 4614 C 101 0 . 041 125 ± 0 . 0001 ± 5 ± 0 . 005 ± 90 329 Svea 22 . 7670 C 78 0 . 055 75 ± 0 . 0001 ± 4 ± 0 . 015 ± 50 478 Tergeste 16 . 10312 L 87 0 . 15 75 ± 0 . 00003 ± 6 ± 0 . 02 ± 45 487 Venetia 13 . 34133 S 70 0 . 21 100 ± 0 . 00002 ± 4 ± 0 . 02 ± 75 Marciniak et al. 2018

Selection effects Shape models TPM Results Summary Thermal inertia of Main Belt Asteroids Harris & Drube 2016

Selection effects Shape models TPM Results Summary Thermal inertia of slow rotators after: Harris & Drube 2016

Selection effects Shape models TPM Results Summary (195) Eurykleia model in thermophysical modelling

Selection effects Shape models TPM Results Summary Thermal lightcurve fit to WISE W4 data (target: 673 Edda) 1.7 W4 data Best fit AM 1 1.6 1.5 Flux (Jy) 1.4 1.3 1.2 1.1 1 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Rotational phase

Selection effects Shape models TPM Results Summary O-C plots for (673) Edda model applied in TPM 2 180 2 60 AM 1 AM 1 160 50 140 1.5 1.5 Wavelength (micron) 120 Aspect angle (deg.) 40 Obs/Mod Obs/Mod 100 1 1 30 80 60 20 0.5 0.5 40 20 10 0 0 0 10 100 2.805 2.81 2.815 2.82 2.825 2.83 2.835 2.84 2.845 Wavelength (micron) Heliocentric distance (au) 2 60 2 180 AM 1 AM 1 160 50 140 1.5 1.5 Wavelength (micron) Aspect angle (deg.) 120 40 Obs/Mod Obs/Mod 100 1 1 30 80 60 20 0.5 0.5 40 20 10 0 0 0 -40 -30 -20 -10 0 10 20 30 40 0 0.2 0.4 0.6 0.8 1 Phase angle (degree) Rotational phase

Selection effects Shape models TPM Results Summary Summary of TPM results for (673) Edda. χ 2 Shape model IR data subset ¯ D ± 3 σ (km) Γ ± 3 σ (SIu) Roughness (rms) m 38 + 6 3 + 67 AM 1 All data 0.47 Med.-high (0.50) − 2 − 3 AM 1 sphere All data 1.83 38 5 Med.-high (0.39) 38 2 + 3 + 37 AM 2 All data 0.59 Extr. high (1.0) − 2 − 3 AM 2 sphere All data 1.76 38 10. Medium (0.44)

Selection effects Shape models TPM Results Summary Rotation Radiometric solution for combined data. Target period Taxonomic Diameter Albedo Thermal inertia [h] type [km] [SI units] 87 + 5 0 . 22 + 0 . 03 4 + 66 100 Hekate 27 . 07027 S − 4 − 0 . 03 − 2 ± 0 . 00006 85 + 7 0 . 065 + 0 . 008 40 + 100 109 Felicitas 13 . 190550 Ch − 5 − 0 . 01 − 36 ± 0 . 000004 87 + 11 15 + 55 195 Eurykleia 16 . 52178 Ch 0 . 06 ± 0 . 02 − 9 − 15 ± 0 . 00002 55 + 2 0 . 047 + 0 . 004 45 + 60 301 Bavaria 12 . 24090 C − 2 − 0 . 003 − 30 ± 0 . 00001 98 + 10 0 . 046 + 0 . 014 335 Roberta 12 . 02713 B unconstrained − 11 − 0 . 008 ± 0 . 00003 72 + 9 0 . 057 + 0 . 009 10 + 140 380 Fiducia 13 . 71723 C − 5 − 0 . 012 − 10 ± 0 . 00002 69 + 11 0 . 052 + 0 . 006 20 + 280 468 Lina 16 . 47838 CPF − 4 − 0 . 014 − 20 ± 0 . 00003 77 + 4 10 + 25 538 Friederike 46 . 739 C 0 . 06 ± 0 . 01 − 2 − 10 ± 0 . 001 46 + 4 0 . 18 + 0 . 02 40 + 120 653 Berenike 12 . 48357 K − 2 − 0 . 03 − 40 ± 0 . 00003 38 + 6 0 . 13 + 0 . 03 3 + 67 673 Edda 22 . 33411 S − 2 − 0 . 05 − 3 ± 0 . 00004 67 + 8 0 . 074 + 0 . 014 20 + 30 834 Burnhamia 13 . 87594 GS − 6 − 0 . 016 − 20 ± 0 . 00002

Selection effects Shape models TPM Results Summary Thermal inertia of slow rotators after: Harris & Drube 2016

Selection effects Shape models TPM Results Summary Thermal inertia normalised to 1 AU vs. size

Selection effects Shape models TPM Results Summary Summary Selection effects: spin and shape models mainly available for short-period, elongated asteroids with extreme obliquities Biased spatial spin axis and size-frequency distributions, lack of detailed models for slow rotators Our targeted survey of 100 long-period, low-amplitude MB asteroids. Gathered over 10 000 hours of lightcurve data in 20 stations worldwide (+ Kepler). Modelled 16 targets from this sample, scaled by TPM using IR data from IRAS, AKARI and WISE Found high, medium and very low thermal inertias Differences due to sub-surface temperatures and different material properties? Indication of fresh and old surfaces connected with formation age and/or size? This work was supported by grant no. 2014/13/D/ST9/01818 from National Science Centre, Poland. The research leading to these results has received funding from the European Union’s Horizon 2020 Research and Innovation Programme, under Grant Agreement no 687378.