The authors acknowledge support from the French grants "Beyond Neptune" ANR-08-BLAN-0177 and "Beyond Neptune II" ANR-11-IS56-0002. Part of the research leading to these results has received funding from the European Research Council under the European Community's H2020 (2014–2020/ERC Grant Agreement No. 669416 "LUCKY STAR"). This work is partly based on observations performed at the European Southern Observatory (ESO), proposals 092.C-0186(B) and 092.C-0186(C), and on observations made at the South African Astronomical Observatory (SAAO). This work has made use of data obtained at the Thai National Observatory on Doi Inthanon, operated by NARIT. Technical support was provided by G. Hau and P. Kabath for the 2014 February 16, observation at ESO/VLT, and by G. Román for the 2016 July 25 observation with the Dobson 60 cm telescope at Granada. A.M. acknowledges the use of Caisey Harlingten's 50 cm telescope for the 2014 February 16 occultation. The 50 cm telescopes used for the Hakos observations belong to the IAS observatory at Hakos/Namibia. E.J. is an FNRS Research Associate. TRAPPIST is a project funded by the Belgian Fund for Scientific Research (Fonds National de la Recherche Scientifique, FRS-FNRS) under grant FRFC 2.5.594.09. F.A.P. and P.-D.J. thank the Dunedin Astronomical Society. E.M. acknowledges support from the Contrato de subvención 205–2014 Fondecyt—Concytec, Perú. M.A. thanks CNPq (Grants 473002/2013-2 and 308721/2011-0) and FAPERJ (Grant E-26/111.488/2013). G.B.-R. acknowledges the support of the CAPES (203.173/2016) and FAPERJ/PAPDRJ (E26/200.464/2015-227833) grants. R.V.-M. thanks grants CNPq-306885/2013, Capes/Cofecub-2506/2015, and FAPERJ: PAPDRJ-45/2013 and E-26/203.026/2015. 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, project SBNAF. The authors acknowledge the use of Sonja Itting-Enke's C14 telescope and the facilities at the Cuno Hoffmeister Memorial Observatory (CHMO), the use of the Skywatcher 16'' telescope of the Deutsche Höhere Privatschule (DHPS) in Windhoek, and the use of the Meade 14 telescope of Space Observation Learning (Rob Johnstone). Funding from Spanish grant AYA-2014-56637-C2-1-P is acknowledged, as is the Proyecto de Excelencia de la Junta de Andalucía, JA 2012-FQM1776. J.I.B.C. acknowledges CNPq grants 308489/2013-6 and 308150/2016-3. The research leading to these results has received funding from the European Union's Horizon 2020 Research and Innovation Programme, under Grant Agreement N. 687378, project SBNAF.

Two narrow and dense rings (called C1R and C2R) were discovered around the Centaur object (10199) Chariklod uring a stellar occultation observed on 2013 June 3. Following this discovery, we planned observations of several occultations by Chariklos system in order to better characterize the physical properties of the ring and main body. Here, we use 12 successful occulations by Chariklo observed between 2014 and 2016. They provide ring profiles (physical width, opacity, edge structure) and constraints on the radii and pole position. Our new observations are currently consistent with the circular ring solution and pole position, to within the ±3.3 km formal uncertainty for the ring radii derived by Braga-Ribas et al. The six resolved C1R profiles reveal significant width variations from ∼5 to 7.5 km. The width of the fainter ring C2R is less constrained, and may vary between 0.1 and 1 km. The inner and outer edges of C1R are consistent with infinitely sharp boundaries, with typical upper limits of one kilometer for the transition zone between the ring and empty space. No constraint on the sharpness of C2Rs edges is available. A 1s upper limit of ∼20 m is derived for the equivalent width of narrow (physical width <4 km) rings up to distances of 12,000 km, counted in the ring plane. © 2017. The American Astronomical Society

Bérard, D. et al.-- Full list of authors: Bérard, D.; Sicardy, B.; Camargo, J. I. B.; Desmars, J.; Braga-Ribas, F.; Ortiz, J. -L.; Duffard, R.; Morales, N.; Meza, E.; Leiva, R.; Benedetti-Rossi, G.; Vieira-Martins, R.; Gomes Júnior, A. -R.; Assafin, M.; Colas, F.; Dauvergne, J. -L.; Kervella, P.; Lecacheux, J.; Maquet, L.; Vachier, F.; Renner, S.; Monard, B.; Sickafoose, A. A.; Breytenbach, H.; Genade, A.; Beisker, W.; Bath, K. -L.; Bode, H. -J.; Backes, M.; Ivanov, V. D.; Jehin, E.; Gillon, M.; Manfroid, J.; Pollock, J.; Tancredi, G.; Roland, S.; Salvo, R.; Vanzi, L.; Herald, D.; Gault, D.; Kerr, S.; Pavlov, H.; Hill, K. M.; Bradshaw, J.; Barry, M. A.; Cool, A.; Lade, B.; Cole, A.; Broughton, J.; Newman, J.; Horvat, R.; Maybour, D.; Giles, D.; Davis, L.; Paton, R. A.; Loader, B.; Pennell, A.; Jaquiery, P. -D.; Brillant, S.; Selman, F.; Dumas, C.; Herrera, C.; Carraro, G.; Monaco, L.; Maury, A.; Peyrot, A.; Teng-Chuen-Yu, J. -P.; Richichi, A.; Irawati, P.; De Witt, C.; Schoenau, P.; Prager, R.; Colazo, C.; Melia, R.; Spagnotto, J.; Blain, A.; Alonso, S.; Román, A.; Santos-Sanz, P.; Rizos, J. -L.; Maestre, J. -L.; Dunham, D.